Echinocyamus pusillus, Ophelia borealis and Abra prismatica in circalittoral fine sand

Summary

UK and Ireland classification

Description

Circalittoral and offshore medium to fine sand (from 40 m to 140 m) characterized by the pea urchin Echinocyamus pusillus, the polychaete Ophelia borealis and the bivalve Abra prismatica. Other species may include the polychaetes Spiophanes bombyxPholoe sp., Exogone spp., Sphaerosyllis bulbosaGoniada maculataChaetozone setosaOwenia fusiformisGlycera lapidumLumbrineris latreilli and Aricidea cerrutii. The bivalves Thracia phaseolina and Asbjornsenia pygmaea and to a lesser extent Spisula elliptica and Timoclea ovata may also be present. This biotope has been found in the central and northern North Sea. In offshore sandier or gravelly sand sediments in the Western Channel and Celitc sea, the biotope may support species indicative of sandy, muddy and mixed sediment. This variant shares the characteristic fauna of Echinocyamus pusillus amongst others, but also supports a wider variety of polychaete worms such as Spiophanes kroyeriMagelona sp. and Tharyx killariensis, and may represent the transition to the biotope SS.SCS.CCS.Blan. (Information from JNCC, 2022).

Depth range

30-50 m, 50-100 m, 100-200 m

Additional information

-

Listed By

Sensitivity reviewHow is sensitivity assessed?

Sensitivity characteristics of the habitat and relevant characteristic species

The biotopes  SS.SSa.IMuSa.FfabMag; SS.SSa.IMuSa.SsubNhom; SS.SSa.CFiSa.EpusOborApri; SS.SSa.CFiSa.ApriBatPo and SS.SSa.CMuSa.AalbNuc represent a continuum along depth and sediment gradients and were grouped as their responses to pressures are probably similar, given the presence of similar species and functional groups. The sensitivity of these biotopes have been reviewed as a group, although the resultant reviews and sensitivity assessments are presented separately for each biotope. The specific biotope assessments have been updated with  information on characterizing species, where this was readily available. However, the resultant assessments are relatively generic. 

Resilience and recovery rates of habitat

This biotope may recover from impacts via in-situ repair of damaged individuals, migration of adults of mobile species such as the errant polychaetes Glycera lapidum and Nephtys cirrosa, amphipods and echinoderms. Adults may also be transported in the water column following washout from sediments.Storm events may lead to the displacement of large numbers of individuals. Most bivalves will be able to reposition within the sediment and some, such as Glycymeris glycymeris, are also able to move and to relocate following displacement and disturbance (Thomas, 1975). For immobile species or where depopulation has occurred over a large area, recovery will depend on recolonization by pelagic larvae.

A large number of species are recorded in the biotopes within the assessed group and there may be large natural variation in species abundance over the course of a year or between years (see Dauvin, 1985 for Timoclea ovata; Fahy et al., 2003 for Spisula solida; Sardá et al., 1999 multispecies). These variations may not alter the biotope classification where habitat parameters, such as sediment type, remain as described in the classification and many of the characteristic species groups are present. For many of the bivalve species studied, recruitment is sporadic and depends on a successful spat fall but recruitment by the characterizing polychaetes may be more reliable. However, due to the large number of pre- and post-recruitment factors such as food supply, predation, and competition, recruitment of venerid bivalves and other species is unpredictable (Olafsson et al., 1994). 

The life history characteristics of the characterizing bivalves and polychaetes and other species were reviewed. Little information was found for Moerella spp. Morton (2009) noted that despite the wide global distribution of the characterizing venerid bivalve, Timoclea ovata, little was known about its anatomy or  basic biology. This appears to be the case for many of the other characterizing venerid bivalves and much more information was available for the polychaete species that occur in this biotope. Two linked factors that may explain this are the greater research effort in soft sediments with higher mud contents where sampling is easier than in coarse sediments. Venerid bivalves are also considered to be under-represented in grab samples (JNCC, 2015), so less is known of their occurrence over ecological and impact gradients.

The venerid bivalves in the biotope reach sexual maturity within two years, spawn at least once a year and have a pelagic dispersal phase (Guillou & Sauriau, 1985; Dauvin, 1985).  No information was found concerning number of gametes produced, but the number is likely to be high as with other bivalves exhibiting planktotrophic development (Olafsson et al., 1994). Recruitment in venerids is likely to be episodic, some species such as Chamelea gallina may be long-lived (11-20 years). The long lifespan & slow growth rate suggest that this group is likely to take several years, even if initial recolonization were to occur rapidly (MES, 2010). Dauvin (1985) reported that Timoclea ovata (studied as Venus ovata) recruitment occurred in July-August in the Bay of Morlaix. However, the population showed considerable pluriannual variations in recruitment, which suggests that recruitment is patchy and/or post settlement processes are highly variable.

The species that are present in the biotope can be broadly characterized as either opportunist species that rapidly colonize disturbed habitats and increase in abundance, or species that are larger and longer-lived and that may be more abundant in an established, mature assemblage.

Species with opportunistic life strategies (small size, rapid maturation and short lifespan of 1-2 years with production of large numbers of small propagules), include the bivalve Spisula solida; and the polychaetes Spiophanes bombyx, Spio filicornis, and Chaetozone setosa; also cumaceans; barnacles Balanus crenatus; and the tube worm Spirobranhchus (formerly Pomatoceros) lamarckii. These are likely to recolonize disturbed areas first, although the actual pattern will depend on recovery of the habitat, season of occurrence and other factors. The recovery of bivalves that recruit episodically and the establishment of a representative age-structured population for larger, longer lived organisms may require longer than two years. In an area that had been subjected to intensive aggregate extraction for 30 years, abundances of juvenile and adults Nephtys cirrosa had greatly increased three years after extraction had stopped (Mouleaert & Hostens, 2007). An area of sand and gravel subject to chronic working for 25 years had not recovered after 6 years when compared to nearby reference sites unimpacted by operations (Boyd et al., 2005). The characterizing Moerella (now Tellina) spp. are a relatively long-lived genus (6-10 years; MES, 2008, 2010) and the number of eggs is likely to be fewer than genera that have planktotrophic larvae.  Similarly, Chamelea sp. and Dosinia sp. are long lived (11-20 years and up to 20 years, respectively; MES, 2008, 2010). While recruitment may be rapid, restoration of the biomass by growth of the colonizing individuals is likely to take many years.

Other longer lived species that may represent a more developed and stable assemblage include the polychaete Owenia fusiformis which lives for 4 years and reproduces annually (Gentil et al., 1990). Nepthys species and Glycera spp. are also longer-lived. Glycera are monotelic having a single breeding period towards the end of their life but may recover through migration and may persist in disturbed sediments through their ability to burrow (Klawe & Dickie, 1957). Glycera spp. have a high potential rate of recolonization of sediments, but the relatively slow growth-rate and long lifespan suggests that recovery of biomass following initial recolonization by post-larvae is likely to take several years (MES, 2010). Following dredging of subtidal sands in summer and autumn to provide material for beach nourishment in the Bay of Blanes, (north-west Mediterranean sea, Spain) recovery was tracked by Sardá et al. (2000). Recolonization in the dredged habitats was rapid, with high densities of Spisula subtruncata and Owenia fusiformis in the spring following dredging, although most of these recruits did not survive summer. However, Glycera spp. and Protodorvillea kefersteini had not recovered within two years (Sardá et al., 2000).

A number of studies have tracked recovery of sand and coarse sand communities following disturbance from fisheries (Gilkinson et al., 2005) and aggregate extraction (Boyd et al., 2005). The available studies confirm the general trend that, following severe disturbance, habitats are recolonized rapidly by opportunistic species (Pearson & Rosenberg, 1978). Experimental deployment of hydraulic clam dredges on a sandy seabed on Banquereau, on the Scotian Shelf, eastern Canada showed that within 2 years of the impact, polychaetes and amphipods had increased in abundance after 1 year (Gilkinson et al., 2005). Two years after dredging, abundances of opportunistic species were generally elevated relative to pre-dredging levels while communities had become numerically dominated (50-70%) by Spiophanes bombyx (Gilkinson et al., 2005). Van Dalfsen et al. (2000) found that polychaetes recolonized a dredged area within 5-10 months (reference from Boyd et al., 2005), with biomass recovery predicted within 2-4 years. The polychaete and amphipods are therefore likely to recover more rapidly than the characterizing bivalves and the biotope classification may revert, during recovery, to a polychaete dominated biotope.

Sardá et al. (1999) tracked annual cycles within a Spisula community in Bay of Blanes (north west Mediterranean sea, Spain) for 4 years. Macroinfaunal abundance peaked in spring, decreased sharply throughout the summer, with low density in autumn and winter. The observed trends were related to a number of species, including Owenia fusiformis and  Glycera sp. that characterize the biotope SS.SSa.CFiSa.EpusOborApri. Inter-annual differences in recruitment of Owenia fusiformis were apparent and this species showed spring/summer increases. Mediomastus fragilis also had spring population peaks but more individuals persisted throughout the year. Protodorvillea kefersteini exhibited a similar pattern with spring recruitment and a population that persisted throughout the year.

Where impacts also alter the sedimentary habitat, recovery of the biotope will also depend on recovery of the habitat to the former condition to support the characteristic biological assemblage. Recovery of sediments will be site-specific and will be influenced by currents, wave action and sediment availability (Desprez, 2000). Except in areas of mobile sands, the process tends to be slow (Kenny & Rees, 1996; Desprez, 2000 and references therein).  Boyd et al. (2005) found that in a site subject to long-term extraction (25 years), extraction scars were still visible after six years and sediment characteristics were still altered in comparison with reference areas, with ongoing effects on the biota.

Resilience assessment. Where resistance is ‘None’ or ‘Low’ and an element of habitat recovery is required, resilience is assessed as ‘Medium’ (2-10 years), based on evidence from aggregate recovery studies in similar habitats including Boyd et al. (2005). Where resistance of the characterizing species is ‘Low’ or ‘Medium’ and the habitat has not been altered, resilience is assessed as ‘High’ as, due to the number of characterizing species and variability in recruitment patterns, it is likely that the biotope would be considered representative and hence recovered after two years although some parameters such as species richness, abundance and biotopes may be altered . Recovery of the seabed from severe physical disturbances that alter sediment character may also take up to 10 years or longer (Le Bot et al., 2010), although extraction of gravel may result in more permanent changes and this will delay recovery.

NB: The resilience and the ability to recover from human induced pressures is a combination of the environmental conditions of the site, the frequency (repeated disturbances versus a one-off event) and the intensity of the disturbance. Recovery of impacted populations will always be mediated by stochastic events and processes acting over different scales including, but not limited to, local habitat conditions, further impacts and processes such as larval-supply and recruitment between populations. Full recovery is defined as the return to the state of the habitat that existed prior to impact. This does not necessarily mean that every component species has returned to its prior condition, abundance or extent but that the relevant functional components are present and the habitat is structurally and functionally recognisable as the initial habitat of interest. It should be noted that the recovery rates are only indicative of the recovery potential. 

Climate Change Pressures

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ResistanceResilienceSensitivity
Global warming (extreme) [Show more]

Global warming (extreme)

Extreme emission scenario (by the end of this century 2081-2100) benchmark of:

  • A 5°C rise in SST and NBT (coastal to the shelf seas),

  • A 6°C rise in surface air temperature (in eulittoral and supralittoral habitats).

  • A 1°C rise in Deep-sea habitats (>200 m) off the continental shelf, and

  • A 5°C rise in surface air temperature in intertidal habitats exclusive to Scotland. Further detail.

Evidence

Sea surface temperatures around the UK currently fall between 6 to 19°C (Huthnance, 2010). Under the middle emission, high emission and extreme scenarios, sea surface temperatures are expected to increase by 3, 4 and 5°C respectively, leading to temperatures increasing to between 22 to 24°C by the end of this century, although northern UK temperatures will be up to 5°C lower. Davenport & Davenport (2005) demonstrated that the limits of thermal tolerance to high and low temperatures reflect distribution of intertidal macroinvertebrate species. Species that occur highest on the shore are more tolerant of a wider range of temperatures than species that occurred low on the shore or subtidally. As subtidal biotopes are less exposed to temperature fluctuations, the characterizing species may be less able to tolerate temperature fluctuations.

There was limited evidence available on the thermal thresholds and thermal ranges for the characterizing species recorded in this biotope, and there is no direct evidence on effects of temperature to these species.

Echinocyamus pusillus is widely distributed in the North East Atlantic Ocean, common in the North Sea and all around British and Irish coastlines. Its range extends from Iceland, Northern Norway and Denmark southwards to the Azores and the Mediterranean (OBIS, 2024). Richter & Bruckschen, (1988) found the variability in annual average temperatures experienced by Echinocyamus pusillus in 15 European locations (Baltic Sea, North Sea, Atlantic Ocean and Mediterranean Sea) was between 9.5 and 20°C. In their study, they found that the Mg content of the high–magnesium calcite skeleton was strongly related to and mainly controlled by the average annual water temperature (Richter & Bruckschen, 1988, cited by Asnaghi et al., 2014).  OBIS (2024) has recorded the species from 5 to 25°C, with the majority of records occurring between 10 to 15°C. Echinocyamus pusillus breeding season occurs in summer months, and planktonic larval development occurs from summer to autumn (Warwick & Pearce, 2020).

Masanja et al. (2023) reported that bivalves were highly sensitive to temperature changes, and even minor deviations from their ideal temperature range could have an adverse impact on their physiology and behaviour. Despite some species acclimating over a long period of time, acute and rapid temperature increases may cause a more substantial stress (Masanja et al., 2023). Successful reproduction and bivalve growth depend on the preferred temperature range of 17 to 24°C (Masanja et al., 2023). Heat stress has been shown to cause cellular damage, oxidative stress, reduced growth and avoidance and deep burrowing behaviour.

The characterizing bivalve Abra prismatica is widespread in the North Sea, around the coasts of Britain, less common on the western coast of Ireland to Norway, but also occurs down to the Mediterranean and northwest Africa. It is also found along the south and west coasts of Iceland and the Faroes. It has been recorded in temperatures ranging from 0 to 25°C (OBIS, 2024). Abra prismatica is similar to Abra alba which also has a relatively wide temperature range of 9 to 23 °C (Rombouts et al., 2012). In a study modelling the effects of climate change on the distribution of benthic species in the Eastern Mediterranean, Moraitis et al. (2019) defined Abra prismatica as a tolerant species, but their model suggested the habitat suitability of the species was expected to decline as temperatures increase under predicted climate change (including scenario RCP 8.5) conditions by 2100. 

In a study on the changes in species occurrence as temperature increased in the English Channel from 1985 to 2012, Gaudin et al. (2018) observed extensions in the distribution range of Abra pristmatica and a more than 50% increase in its spatial occurrence in response to an increase in temperature over the time period. The trends observed in the characterising Echinocyamus pusillus were unclear. 

The characterizing polychaete Ophelia borealis is widespread around the British Isles and the North Sea but less common on the Irish coasts. OBIS (2024) recorded this species from 0 to 20°C, with the majority of records occurring between 10 to 15°C. Similarly, Rombouts et al., (2012) defined the optimal temperature preferences of Ophelia borealis as narrow, between 9 and 16°C. The predominantly northern distribution of Ophelia borealis could suggest it is likely to move further northward as the climate changes and temperature shifts out of its preferred range, particularly as it is a cold temperate species. Their model suggested that Ophelia borealis will retreat from the Western English Channel to cooler northern regions of the North Sea due to warming by the end of the century (Rombouts et al., 2012). In the North Sea Ophelia borealis was observed to decrease in abundance between 1986 and 2000 largely associated with an increase in sea surface temperature (Kröncke et al., 2011; cited by Gaudin et al., 2018).

Temperature cues influence the timing of gametogenesis and spawning in several species present in the biotope. For example, many polychaete species including Mediomastus fragilis, Owenia fusiformis and Protodorvillea kefersteini recruit in spring/early summer (Sardá et al., 1999).

Sensitivity assessment. The distribution and available evidence on temperature tolerance of characterizing species Echinocyamus pusillus and Abra prismatica suggest both species may be able to withstand predicted global warming temperatures. For example, all of the characteristic polychaetes occur in the Mediterranean Sea where sea surface temperatures can reach 28°C in summer months (www.seatemperature.org). However, predicted models suggest prolonged exposure to increased temperatures (under climate change scenarios) may reduce the habitat suitability in the Mediterranean for Abra prismatica (Moraitis et al., 2019). In addition, evidence suggests cold temperate species Ophelia borealis may migrate northwards due to temperatures increasing out of its preferred range, suggesting the species may be vulnerable to global warming.

Therefore, for all three scenarios (middle and high emission and extreme scenarios) resistance is assessed as ‘Medium’ to represent the potential loss or movement of some characteristic species and resilience is assessed as ‘Very Low’, as loss is likely to be a long-term decline, due to the long-term nature of ocean warming. Hence, sensitivity is assessed as ‘Medium’ to ocean warming under all three scenarios, albeit with ‘Low’ confidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Global warming (high) [Show more]

Global warming (high)

High emission scenario (by the end of this century 2081-2100) benchmark of:

  • A 4°C rise in SST, NBT (coastal to the shelf seas) and surface air temperature (in eulittoral and supralittoral habitats).

  • A 1°C rise in Deep-sea habitats (>200 m) off the continental shelf, and

  • A 3°C rise in surface air temperature in intertidal habitats exclusive to Scotland. Further detail.

Evidence

Sea surface temperatures around the UK currently fall between 6 to 19°C (Huthnance, 2010). Under the middle emission, high emission and extreme scenarios, sea surface temperatures are expected to increase by 3, 4 and 5°C respectively, leading to temperatures increasing to between 22 to 24°C by the end of this century, although northern UK temperatures will be up to 5°C lower. Davenport & Davenport (2005) demonstrated that the limits of thermal tolerance to high and low temperatures reflect distribution of intertidal macroinvertebrate species. Species that occur highest on the shore are more tolerant of a wider range of temperatures than species that occurred low on the shore or subtidally. As subtidal biotopes are less exposed to temperature fluctuations, the characterizing species may be less able to tolerate temperature fluctuations.

There was limited evidence available on the thermal thresholds and thermal ranges for the characterizing species recorded in this biotope, and there is no direct evidence on effects of temperature to these species.

Echinocyamus pusillus is widely distributed in the North East Atlantic Ocean, common in the North Sea and all around British and Irish coastlines. Its range extends from Iceland, Northern Norway and Denmark southwards to the Azores and the Mediterranean (OBIS, 2024). Richter & Bruckschen, (1988) found the variability in annual average temperatures experienced by Echinocyamus pusillus in 15 European locations (Baltic Sea, North Sea, Atlantic Ocean and Mediterranean Sea) was between 9.5 and 20°C. In their study, they found that the Mg content of the high–magnesium calcite skeleton was strongly related to and mainly controlled by the average annual water temperature (Richter & Bruckschen, 1988, cited by Asnaghi et al., 2014).  OBIS (2024) has recorded the species from 5 to 25°C, with the majority of records occurring between 10 to 15°C. Echinocyamus pusillus breeding season occurs in summer months, and planktonic larval development occurs from summer to autumn (Warwick & Pearce, 2020).

Masanja et al. (2023) reported that bivalves were highly sensitive to temperature changes, and even minor deviations from their ideal temperature range could have an adverse impact on their physiology and behaviour. Despite some species acclimating over a long period of time, acute and rapid temperature increases may cause a more substantial stress (Masanja et al., 2023). Successful reproduction and bivalve growth depend on the preferred temperature range of 17 to 24°C (Masanja et al., 2023). Heat stress has been shown to cause cellular damage, oxidative stress, reduced growth and avoidance and deep burrowing behaviour.

The characterizing bivalve Abra prismatica is widespread in the North Sea, around the coasts of Britain, less common on the western coast of Ireland to Norway, but also occurs down to the Mediterranean and northwest Africa. It is also found along the south and west coasts of Iceland and the Faroes. It has been recorded in temperatures ranging from 0 to 25°C (OBIS, 2024). Abra prismatica is similar to Abra alba which also has a relatively wide temperature range of 9 to 23 °C (Rombouts et al., 2012). In a study modelling the effects of climate change on the distribution of benthic species in the Eastern Mediterranean, Moraitis et al. (2019) defined Abra prismatica as a tolerant species, but their model suggested the habitat suitability of the species was expected to decline as temperatures increase under predicted climate change (including scenario RCP 8.5) conditions by 2100. 

In a study on the changes in species occurrence as temperature increased in the English Channel from 1985 to 2012, Gaudin et al. (2018) observed extensions in the distribution range of Abra pristmatica and a more than 50% increase in its spatial occurrence in response to an increase in temperature over the time period. The trends observed in the characterising Echinocyamus pusillus were unclear. 

The characterizing polychaete Ophelia borealis is widespread around the British Isles and the North Sea but less common on the Irish coasts. OBIS (2024) recorded this species from 0 to 20°C, with the majority of records occurring between 10 to 15°C. Similarly, Rombouts et al., (2012) defined the optimal temperature preferences of Ophelia borealis as narrow, between 9 and 16°C. The predominantly northern distribution of Ophelia borealis could suggest it is likely to move further northward as the climate changes and temperature shifts out of its preferred range, particularly as it is a cold temperate species. Their model suggested that Ophelia borealis will retreat from the Western English Channel to cooler northern regions of the North Sea due to warming by the end of the century (Rombouts et al., 2012). In the North Sea Ophelia borealis was observed to decrease in abundance between 1986 and 2000 largely associated with an increase in sea surface temperature (Kröncke et al., 2011; cited by Gaudin et al., 2018).

Temperature cues influence the timing of gametogenesis and spawning in several species present in the biotope. For example, many polychaete species including Mediomastus fragilis, Owenia fusiformis and Protodorvillea kefersteini recruit in spring/early summer (Sardá et al., 1999).

Sensitivity assessment. The distribution and available evidence on temperature tolerance of characterizing species Echinocyamus pusillus and Abra prismatica suggest both species may be able to withstand predicted global warming temperatures. For example, all of the characteristic polychaetes occur in the Mediterranean Sea where sea surface temperatures can reach 28°C in summer months (www.seatemperature.org). However, predicted models suggest prolonged exposure to increased temperatures (under climate change scenarios) may reduce the habitat suitability in the Mediterranean for Abra prismatica (Moraitis et al., 2019). In addition, evidence suggests cold temperate species Ophelia borealis may migrate northwards due to temperatures increasing out of its preferred range, suggesting the species may be vulnerable to global warming.

Therefore, for all three scenarios (middle and high emission and extreme scenarios) resistance is assessed as ‘Medium’ to represent the potential loss or movement of some characteristic species and resilience is assessed as ‘Very Low’, as loss is likely to be a long-term decline, due to the long-term nature of ocean warming. Hence, sensitivity is assessed as ‘Medium’ to ocean warming under all three scenarios, albeit with ‘Low’ confidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Global warming (middle) [Show more]

Global warming (middle)

Middle emission scenario (by the end of this century 2081-2100) benchmark of:

  • A 3°C rise in SST, NBT (coastal to the shelf seas) and surface air temperature (in eulittoral and supralittoral habitats).

  • A 1°C rise in Deep-sea habitats (>200 m) off the continental shelf.

  • A 2°C rise in surface air temperature in intertidal habitats exclusive to Scotland. Further detail.

Evidence

Sea surface temperatures around the UK currently fall between 6 to 19°C (Huthnance, 2010). Under the middle emission, high emission and extreme scenarios, sea surface temperatures are expected to increase by 3, 4 and 5°C respectively, leading to temperatures increasing to between 22 to 24°C by the end of this century, although northern UK temperatures will be up to 5°C lower. Davenport & Davenport (2005) demonstrated that the limits of thermal tolerance to high and low temperatures reflect distribution of intertidal macroinvertebrate species. Species that occur highest on the shore are more tolerant of a wider range of temperatures than species that occurred low on the shore or subtidally. As subtidal biotopes are less exposed to temperature fluctuations, the characterizing species may be less able to tolerate temperature fluctuations.

There was limited evidence available on the thermal thresholds and thermal ranges for the characterizing species recorded in this biotope, and there is no direct evidence on effects of temperature to these species.

Echinocyamus pusillus is widely distributed in the North East Atlantic Ocean, common in the North Sea and all around British and Irish coastlines. Its range extends from Iceland, Northern Norway and Denmark southwards to the Azores and the Mediterranean (OBIS, 2024). Richter & Bruckschen, (1988) found the variability in annual average temperatures experienced by Echinocyamus pusillus in 15 European locations (Baltic Sea, North Sea, Atlantic Ocean and Mediterranean Sea) was between 9.5 and 20°C. In their study, they found that the Mg content of the high–magnesium calcite skeleton was strongly related to and mainly controlled by the average annual water temperature (Richter & Bruckschen, 1988, cited by Asnaghi et al., 2014).  OBIS (2024) has recorded the species from 5 to 25°C, with the majority of records occurring between 10 to 15°C. Echinocyamus pusillus breeding season occurs in summer months, and planktonic larval development occurs from summer to autumn (Warwick & Pearce, 2020).

Masanja et al. (2023) reported that bivalves were highly sensitive to temperature changes, and even minor deviations from their ideal temperature range could have an adverse impact on their physiology and behaviour. Despite some species acclimating over a long period of time, acute and rapid temperature increases may cause a more substantial stress (Masanja et al., 2023). Successful reproduction and bivalve growth depend on the preferred temperature range of 17 to 24°C (Masanja et al., 2023). Heat stress has been shown to cause cellular damage, oxidative stress, reduced growth and avoidance and deep burrowing behaviour.

The characterizing bivalve Abra prismatica is widespread in the North Sea, around the coasts of Britain, less common on the western coast of Ireland to Norway, but also occurs down to the Mediterranean and northwest Africa. It is also found along the south and west coasts of Iceland and the Faroes. It has been recorded in temperatures ranging from 0 to 25°C (OBIS, 2024). Abra prismatica is similar to Abra alba which also has a relatively wide temperature range of 9 to 23 °C (Rombouts et al., 2012). In a study modelling the effects of climate change on the distribution of benthic species in the Eastern Mediterranean, Moraitis et al. (2019) defined Abra prismatica as a tolerant species, but their model suggested the habitat suitability of the species was expected to decline as temperatures increase under predicted climate change (including scenario RCP 8.5) conditions by 2100. 

In a study on the changes in species occurrence as temperature increased in the English Channel from 1985 to 2012, Gaudin et al. (2018) observed extensions in the distribution range of Abra pristmatica and a more than 50% increase in its spatial occurrence in response to an increase in temperature over the time period. The trends observed in the characterising Echinocyamus pusillus were unclear. 

The characterizing polychaete Ophelia borealis is widespread around the British Isles and the North Sea but less common on the Irish coasts. OBIS (2024) recorded this species from 0 to 20°C, with the majority of records occurring between 10 to 15°C. Similarly, Rombouts et al., (2012) defined the optimal temperature preferences of Ophelia borealis as narrow, between 9 and 16°C. The predominantly northern distribution of Ophelia borealis could suggest it is likely to move further northward as the climate changes and temperature shifts out of its preferred range, particularly as it is a cold temperate species. Their model suggested that Ophelia borealis will retreat from the Western English Channel to cooler northern regions of the North Sea due to warming by the end of the century (Rombouts et al., 2012). In the North Sea Ophelia borealis was observed to decrease in abundance between 1986 and 2000 largely associated with an increase in sea surface temperature (Kröncke et al., 2011; cited by Gaudin et al., 2018).

Temperature cues influence the timing of gametogenesis and spawning in several species present in the biotope. For example, many polychaete species including Mediomastus fragilis, Owenia fusiformis and Protodorvillea kefersteini recruit in spring/early summer (Sardá et al., 1999).

Sensitivity assessment. The distribution and available evidence on temperature tolerance of characterizing species Echinocyamus pusillus and Abra prismatica suggest both species may be able to withstand predicted global warming temperatures. For example, all of the characteristic polychaetes occur in the Mediterranean Sea where sea surface temperatures can reach 28°C in summer months (www.seatemperature.org). However, predicted models suggest prolonged exposure to increased temperatures (under climate change scenarios) may reduce the habitat suitability in the Mediterranean for Abra prismatica (Moraitis et al., 2019). In addition, evidence suggests cold temperate species Ophelia borealis may migrate northwards due to temperatures increasing out of its preferred range, suggesting the species may be vulnerable to global warming.

Therefore, for all three scenarios (middle and high emission and extreme scenarios) resistance is assessed as ‘Medium’ to represent the potential loss or movement of some characteristic species and resilience is assessed as ‘Very Low’, as loss is likely to be a long-term decline, due to the long-term nature of ocean warming. Hence, sensitivity is assessed as ‘Medium’ to ocean warming under all three scenarios, albeit with ‘Low’ confidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Marine heatwaves (high) [Show more]

Marine heatwaves (high)

High emission scenario benchmark: A marine heatwave occurring every two years, with a mean duration of 120 days, and a maximum intensity of 3.5°C. Further detail.

Evidence

Marine heatwaves due to increased air-sea heat flux are predicted to occur more frequently, last for longer and at increased intensity by the end of this century under both middle and high emission scenarios (Frölicher et al., 2018). Climate change will not only shift mean sea surface temperatures but will also increase the intensity of extreme events, exerting additional stress on ecosystems.

There is limited evidence on the upper thermal limits of Echinocyamus pusillus but the species appears to be tolerance of a wide range of temperatures (see global warming above), due to wide global distribution. Richter & Bruckschen (1988) found the variability in annual average temperatures experienced by Echinocyamus pusillus in 15 European locations (Baltic Sea, North Sea, Atlantic Ocean and Mediterranean Sea) was between 9.5 and 20°C. OBIS (2024), has recorded the species from 5 to 25°C, with the majority of records between 10 to 15°C.

There is also limited evidence available on the thermal thresholds and thermal ranges for the characterizing bivalves recorded in this biotope. Masanja et al. (2023) found that bivalves were highly sensitive to temperature changes, and even minor deviations from their ideal temperature range could have an adverse impact on their physiology and behaviour. Despite some species acclimating over a long period of time, acute and rapid temperature increases may cause a more substantial stress (Masanja et al., 2023). Successful reproduction and bivalve growth depend on the preferred temperature range of 17 to 24°C (Masanja et al., 2023). Heat stress has been shown to cause cellular damage, oxidative stress, reduced growth and avoidance and deep burrowing behaviour. The distribution of characterizing bivalve Abra prismatica suggests it is likely to experience a wide range of temperature regimes due to its distribution (see global warming above).

The polychaete Ophelia borealis has a narrow optimal temperature preference of 9 to 16°C (Rombouts et al., 2012). The species’ predominantly northern distribution (see global warming above) could suggest it is likely to move further northward as the climate changes and temperature shifts out of its preferred range, particularly as it is a cold temperate species. In their model Ophelia borealis will retreat from the Western English Channel to cooler northern regions of the North Sea due to warming by the end of the century (Rombouts et al., 2012). In the North Sea Ophelia borealis was observed to decrease in abundance between 1986 and 2000, largely associated with an increase in sea surface temperature (Kröncke et al., 2011; cited by Gaudin et al., 2018).

Sensitivity assessment. Under the middle emission scenario, if heatwaves occurred every three years, with a maximum intensity of 2°C for 80 days by the end of this century, summer sea temperatures could reach up to 24°C in southern England. Under the high emission scenario, if heatwaves occur every two years by the end of this century, reaching a maximum intensity of 3.5°C for 120 days, this could lead to the heatwave lasting the entire summer with temperatures reaching up to 26.5°C. As a precautionary approach, resistance is assessed as ‘Medium’. The resilience of the characterizing populations is likely to be ‘Medium’ (2-10 years), hence, recovery may be interrupted by the occurrence of a further heatwave. Therefore, resilience has been assessed as ‘Very low’, leading to a sensitivity assessment of ‘Medium’ but with low confidence due to lack of direct evidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Marine heatwaves (middle) [Show more]

Marine heatwaves (middle)

Middle emission scenario benchmark:  A marine heatwave occurring every three years, with a mean duration of 80 days, with a maximum intensity of 2°C. Further detail.

Evidence

Marine heatwaves due to increased air-sea heat flux are predicted to occur more frequently, last for longer and at increased intensity by the end of this century under both middle and high emission scenarios (Frölicher et al., 2018). Climate change will not only shift mean sea surface temperatures but will also increase the intensity of extreme events, exerting additional stress on ecosystems.

There is limited evidence on the upper thermal limits of Echinocyamus pusillus but the species appears to be tolerance of a wide range of temperatures (see global warming above), due to wide global distribution. Richter & Bruckschen (1988) found the variability in annual average temperatures experienced by Echinocyamus pusillus in 15 European locations (Baltic Sea, North Sea, Atlantic Ocean and Mediterranean Sea) was between 9.5 and 20°C. OBIS (2024), has recorded the species from 5 to 25°C, with the majority of records between 10 to 15°C.

There is also limited evidence available on the thermal thresholds and thermal ranges for the characterizing bivalves recorded in this biotope. Masanja et al. (2023) found that bivalves were highly sensitive to temperature changes, and even minor deviations from their ideal temperature range could have an adverse impact on their physiology and behaviour. Despite some species acclimating over a long period of time, acute and rapid temperature increases may cause a more substantial stress (Masanja et al., 2023). Successful reproduction and bivalve growth depend on the preferred temperature range of 17 to 24°C (Masanja et al., 2023). Heat stress has been shown to cause cellular damage, oxidative stress, reduced growth and avoidance and deep burrowing behaviour. The distribution of characterizing bivalve Abra prismatica suggests it is likely to experience a wide range of temperature regimes due to its distribution (see global warming above).

The polychaete Ophelia borealis has a narrow optimal temperature preference of 9 to 16°C (Rombouts et al., 2012). The species’ predominantly northern distribution (see global warming above) could suggest it is likely to move further northward as the climate changes and temperature shifts out of its preferred range, particularly as it is a cold temperate species. In their model Ophelia borealis will retreat from the Western English Channel to cooler northern regions of the North Sea due to warming by the end of the century (Rombouts et al., 2012). In the North Sea Ophelia borealis was observed to decrease in abundance between 1986 and 2000, largely associated with an increase in sea surface temperature (Kröncke et al., 2011; cited by Gaudin et al., 2018).

Sensitivity assessment. Under the middle emission scenario, if heatwaves occurred every three years, with a maximum intensity of 2°C for 80 days by the end of this century, summer sea temperatures could reach up to 24°C in southern England. Under the high emission scenario, if heatwaves occur every two years by the end of this century, reaching a maximum intensity of 3.5°C for 120 days, this could lead to the heatwave lasting the entire summer with temperatures reaching up to 26.5°C. As a precautionary approach, resistance is assessed as ‘Medium’. The resilience of the characterizing populations is likely to be ‘Medium’ (2-10 years), hence, recovery may be interrupted by the occurrence of a further heatwave. Therefore, resilience has been assessed as ‘Very low’, leading to a sensitivity assessment of ‘Medium’ but with low confidence due to lack of direct evidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Ocean acidification (high) [Show more]

Ocean acidification (high)

High emission scenario benchmark: a further decrease in pH of 0.35 (annual mean) and corresponding 120% increase in H+ ions , seasonal aragonite saturation of 20% of UK coastal waters and North Sea bottom waters, and the aragonite saturation horizon in the NE Atlantic, off the continental shelf, occurring at a depth of 400 m by the end of this century 2081-2100. Further detail 

Evidence

Increasing levels of CO2 in the atmosphere have led to the average pH of sea surface waters dropping from 8.25 in the 1700s to 8.14 in the 1990s (Jacobson, 2005). There is no direct evidence on the effects of ocean acidification on the characterizing species Echinocyamus pusillus, Abra prismatica or Ophelia borealis.

Ocean acidification is expected to negatively affect reproduction (fecundity and sperm mobility) of annelids and molluscs (David, 2021). Ophelia borealis is not a calcifying polychaete with calcareous tubes and therefore, might be able to withstand effects of ocean acidification. Calcifying polychaetes (Serpuild polychaetes) are vulnerable to more acidic oceans due to dissolution of the calcite and aragonite, which impact he structural integrity of the polychaetes tubes (David, 2021). Studies on free-living benthic polychaetes  found an increase in metabolic rate, oxidative stress and reduction in sperm motility in hypercapnic conditions (David, 2021). Polychaete species that live in CO2 vents are physiologically more tolerant to elevated pCO2 levels.

Evidence suggests that bivalves are negatively impacted by ocean acidification. An increase in pCO2 decreases the calcium carbonate saturation of aragonite and calcite, which leads to negative effects on growth and calcification of bivalves (Tan & Zheng, 2020). The calcium carbonate shells of bivalves provide refuge from various stressors. Reduced calcification rate was observed at different bivalve life stages, but the greatest rate of shell dissolution was found in the larval stage, which suggests these early life stages are highly sensitive. Further evidence suggests acidification impacts growth rates, development in early life stages and survival amongst bivalve species (Tan & Zheng, 2020). For example, Garrard et al., 2014 found a decrease in the abundance and species richness of bivalves in response to low pH levels (minimum pH was 7.1). Changes in the community was likely due to indirect effects of acidification rather than direct effects (Garrard et al., 2014). Despite no evidence on the effects of Abra prismatica, the evidence on similar species Abra alba showed a reduction in feeding frequency in reduced seawater pH (pH 7.9 from ambient pH 8.2). This was a behavioural change to reduce intake of low pH during respiration and feeding, which may lead in the long term to a decline in fitness and survival in acidification conditions (Vlaminck et al., 2023). In addition, a reduction in respiration, calcification rates, energy intake and increase in metabolic losses were reported in Abra alba in lowered pH of around 7.7 (Vlaminck et al., 2022).

Sea urchins have been widely researched in regard to the effects of ocean acidification. They are important calcifiers that use high magnesium calcite (the most soluble form of calcium carbonate) to build their skeleton, spines and grazing apparatus (Ashnaghi et al., 2014). Hence, they are threatened by ocean acidification (Asnicar & Marin, 2022). Evidence has shown a parabolic calcification response, where a positive response is observed under intermediate pCO2 and negative response is observed under high pCO2. However, the response is not universal and varies between species (Wicks & Roberts, 2012). 

Ocean acidification affects sea urchin reproduction and early life stages differently across species. Adaptive metabolic suppression to help with survival in stressful conditions was observed in sea urchin species in response to a decrease in pH. Sea urchins exposed in long term experiments and those which inhabit CO2 vents showed acclimation (Asnicar & Marin, 2022). However, this acclimation and ability to maintain calcification may come at a cost in mechanical problems and degradation of calcareous structures (Asnicar & Marin, 2022). While a pH decrease altered larval shape, swimming abilities remained unaffected by reduced pH level. (Bryne et al., 2013, Chan et al., 2016 cited by Espinel–Velesco et al., 2018). Some species of sea urchin (Paracentrotus lividus and Strongylocentrotus droebachiensis) have shown delayed settlement in reduced pH levels (Garcia et al., 2015, Dupont et al., 2013 cited by Espinel–Velesco et al., 2018). Newly settled sea urchins exhibit increased metabolic rates, robust survival and faster growth in near future pH levels. However, poor development in the length of calcareous spines and altered morphology were observed in low pH levels (Espinel–Velesco et al., 2018). Heightened calcification tolerance was reported in cold adapted Antarctic urchin larvae. However, Tripneustes gratilla larvae showed reduced calcification due to a pH decrease of 0.35 units (Wicks & Roberts, 2012). Strongylocentrotus droebachiensis showed improved responsiveness and enhanced survival under high CO2 and low pH conditions, with a decrease in egg production as a short-term response. Overall, in their review, Asnicar & Marin, (2022) suggested the adult sea urchins can tolerate a pH reduction smaller than 0.4 units. However, as there are differences in the response of sea urchin species to ocean acidification and there is an absence of direct evidence on characterising Echinocyamus pusillus, its possible response is uncertain.

Sensitivity assessment. No direct evidence of the impact of ocean acidification on the characterizing species Echinocyamus pusillus, Abra prismatica or Ophelia borealis was found. However, Ophelia borealis is a non-calcifying polychaete and likely be tolerant of ocean acidification expected for the end of this century. In addition, sea urchin adult populations may be able to tolerate a 0.4 pH decrease but the impacts vary at a species level. Therefore, under both the middle and high emission scenarios the biotope is assessed as having ‘Medium’ resistance to ocean acidification to represent the possible loss of bivalve species and reduced larval recruitment in echinoderms. Resilience is assessed as ‘Very low’, and sensitivity as ‘Medium’ at the benchmark level with ‘Low’ confidence due to lack of direct evidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Ocean acidification (middle) [Show more]

Ocean acidification (middle)

Middle emission scenario benchmark: a further decrease in pH of 0.15 (annual mean) and corresponding 35% increase in H+ ions with no coastal aragonite undersaturation and the aragonite saturation horizon in the NE Atlantic, off the continental shelf, at a depth of 800 m by the end of this century 2081-2100. Further detail.

Evidence

Increasing levels of CO2 in the atmosphere have led to the average pH of sea surface waters dropping from 8.25 in the 1700s to 8.14 in the 1990s (Jacobson, 2005). There is no direct evidence on the effects of ocean acidification on the characterizing species Echinocyamus pusillus, Abra prismatica or Ophelia borealis.

Ocean acidification is expected to negatively affect reproduction (fecundity and sperm mobility) of annelids and molluscs (David, 2021). Ophelia borealis is not a calcifying polychaete with calcareous tubes and therefore, might be able to withstand effects of ocean acidification. Calcifying polychaetes (Serpuild polychaetes) are vulnerable to more acidic oceans due to dissolution of the calcite and aragonite, which impact he structural integrity of the polychaetes tubes (David, 2021). Studies on free-living benthic polychaetes  found an increase in metabolic rate, oxidative stress and reduction in sperm motility in hypercapnic conditions (David, 2021). Polychaete species that live in CO2 vents are physiologically more tolerant to elevated pCO2 levels.

Evidence suggests that bivalves are negatively impacted by ocean acidification. An increase in pCO2 decreases the calcium carbonate saturation of aragonite and calcite, which leads to negative effects on growth and calcification of bivalves (Tan & Zheng, 2020). The calcium carbonate shells of bivalves provide refuge from various stressors. Reduced calcification rate was observed at different bivalve life stages, but the greatest rate of shell dissolution was found in the larval stage, which suggests these early life stages are highly sensitive. Further evidence suggests acidification impacts growth rates, development in early life stages and survival amongst bivalve species (Tan & Zheng, 2020). For example, Garrard et al., 2014 found a decrease in the abundance and species richness of bivalves in response to low pH levels (minimum pH was 7.1). Changes in the community was likely due to indirect effects of acidification rather than direct effects (Garrard et al., 2014). Despite no evidence on the effects of Abra prismatica, the evidence on similar species Abra alba showed a reduction in feeding frequency in reduced seawater pH (pH 7.9 from ambient pH 8.2). This was a behavioural change to reduce intake of low pH during respiration and feeding, which may lead in the long term to a decline in fitness and survival in acidification conditions (Vlaminck et al., 2023). In addition, a reduction in respiration, calcification rates, energy intake and increase in metabolic losses were reported in Abra alba in lowered pH of around 7.7 (Vlaminck et al., 2022).

Sea urchins have been widely researched in regard to the effects of ocean acidification. They are important calcifiers that use high magnesium calcite (the most soluble form of calcium carbonate) to build their skeleton, spines and grazing apparatus (Ashnaghi et al., 2014). Hence, they are threatened by ocean acidification (Asnicar & Marin, 2022). Evidence has shown a parabolic calcification response, where a positive response is observed under intermediate pCO2 and negative response is observed under high pCO2. However, the response is not universal and varies between species (Wicks & Roberts, 2012). 

Ocean acidification affects sea urchin reproduction and early life stages differently across species. Adaptive metabolic suppression to help with survival in stressful conditions was observed in sea urchin species in response to a decrease in pH. Sea urchins exposed in long term experiments and those which inhabit CO2 vents showed acclimation (Asnicar & Marin, 2022). However, this acclimation and ability to maintain calcification may come at a cost in mechanical problems and degradation of calcareous structures (Asnicar & Marin, 2022). While a pH decrease altered larval shape, swimming abilities remained unaffected by reduced pH level. (Bryne et al., 2013, Chan et al., 2016 cited by Espinel–Velesco et al., 2018). Some species of sea urchin (Paracentrotus lividus and Strongylocentrotus droebachiensis) have shown delayed settlement in reduced pH levels (Garcia et al., 2015, Dupont et al., 2013 cited by Espinel–Velesco et al., 2018). Newly settled sea urchins exhibit increased metabolic rates, robust survival and faster growth in near future pH levels. However, poor development in the length of calcareous spines and altered morphology were observed in low pH levels (Espinel–Velesco et al., 2018). Heightened calcification tolerance was reported in cold adapted Antarctic urchin larvae. However, Tripneustes gratilla larvae showed reduced calcification due to a pH decrease of 0.35 units (Wicks & Roberts, 2012). Strongylocentrotus droebachiensis showed improved responsiveness and enhanced survival under high CO2 and low pH conditions, with a decrease in egg production as a short-term response. Overall, in their review, Asnicar & Marin, (2022) suggested the adult sea urchins can tolerate a pH reduction smaller than 0.4 units. However, as there are differences in the response of sea urchin species to ocean acidification and there is an absence of direct evidence on characterising Echinocyamus pusillus, its possible response is uncertain.

Sensitivity assessment. No direct evidence of the impact of ocean acidification on the characterizing species Echinocyamus pusillus, Abra prismatica or Ophelia borealis was found. However, Ophelia borealis is a non-calcifying polychaete and likely be tolerant of ocean acidification expected for the end of this century. In addition, sea urchin adult populations may be able to tolerate a 0.4 pH decrease but the impacts vary at a species level. Therefore, under both the middle and high emission scenarios the biotope is assessed as having ‘Medium’ resistance to ocean acidification to represent the possible loss of bivalve species and reduced larval recruitment in echinoderms. Resilience is assessed as ‘Very low’, and sensitivity as ‘Medium’ at the benchmark level with ‘Low’ confidence due to lack of direct evidence.

Medium
Low
NR
NR
Help
Very Low
High
High
High
Help
Medium
Low
NR
NR
Help
Sea level rise (extreme) [Show more]

Sea level rise (extreme)

Extreme scenario benchmark: a 107 cm rise in average UK by the end of this century (2018-2100). Further detail.

Evidence

Sea-level rise is occurring through a combination of thermal expansion and ice melt. Sea levels have risen 1-3 mm/yr in the last century (Cazenave & Nerem, 2004, Church et al., 2004, Church & White, 2006). The most recent projections on sea-level rise suggest a rise of 50 cm under the middle emission scenario, 70 cm under the high emission scenario, and 107 cm under the extreme scenario. 

Understanding how sea-level rise will affect tidal energy, and the tide-swept nature of a habitat, is fraught with uncertainty, although evidence appears to suggest that any alterations will be non-linear (Pickering et al., 2012, Li et al., 2016). Modelling potential outcomes of sea-level rise on the tidal and residual currents in the Bohai Sea, China showed effects were site dependent, with energy either increasing or decreasing (Li et al., 2016). Similarly, Pickering et al. (2012) found a similar pattern around the UK for tidal amplitude. The effects of sea-level rise and increased wave action may be increased further due to storms and storm surges. IPCC (2019) note that the frequency of extreme sea-level events (e.g. due to storms) are predicted to increase as sea-level rises, however there is no consensus on the future storm and, hence, wave climate around UK coasts (Mossman et al., 2015; Lowe et al., 2018; Palmer et al., 2018).

The characterizing Echinocyamus pusillus is distributed from the intertidal down to 1,250 m (Ghiold, 1982). Abra prismatic occurs in the sublittoral zone from the low-water mark down to 500 m (Oliver et al., 2016). Most Ophelia species inhabit the intertidal fringe to shallow subtidal down to depths of about 100 m (Parapar et al., 2021), Ophelia borealis has showed depth preferences shallower than 250 m (Rombouts et al., 2012)

Sensitivity assessment. This habitat occurs from 30 to 200 m and the characterizing echinoderm, polychaete and bivalve species are abundant at depths more than 200 m, suggesting these species will be tolerant of future sea-level rise. Therefore, an increase in sea-level rise is unlikely to have a large impact on this biotope and therefore resistance to sea-level rise has been assessed as ‘High’ for the middle (50 cm), and high (70 cm) emission scenario, and for the extreme scenario (107 cm). As no recovery is deemed necessary, resilience has been assessed as ‘High’, and therefore this species has been classified as ‘Not sensitive’ to sea-level rise at each of the benchmarks.

High
Low
NR
NR
Help
High
High
High
High
Help
Not sensitive
Low
NR
NR
Help
Sea level rise (high) [Show more]

Sea level rise (high)

High emission scenario benchmark: a 70 cm rise in average UK by the end of this century (2018-2100). Further detail.

Evidence

Sea-level rise is occurring through a combination of thermal expansion and ice melt. Sea levels have risen 1-3 mm/yr in the last century (Cazenave & Nerem, 2004, Church et al., 2004, Church & White, 2006). The most recent projections on sea-level rise suggest a rise of 50 cm under the middle emission scenario, 70 cm under the high emission scenario, and 107 cm under the extreme scenario. 

Understanding how sea-level rise will affect tidal energy, and the tide-swept nature of a habitat, is fraught with uncertainty, although evidence appears to suggest that any alterations will be non-linear (Pickering et al., 2012, Li et al., 2016). Modelling potential outcomes of sea-level rise on the tidal and residual currents in the Bohai Sea, China showed effects were site dependent, with energy either increasing or decreasing (Li et al., 2016). Similarly, Pickering et al. (2012) found a similar pattern around the UK for tidal amplitude. The effects of sea-level rise and increased wave action may be increased further due to storms and storm surges. IPCC (2019) note that the frequency of extreme sea-level events (e.g. due to storms) are predicted to increase as sea-level rises, however there is no consensus on the future storm and, hence, wave climate around UK coasts (Mossman et al., 2015; Lowe et al., 2018; Palmer et al., 2018).

The characterizing Echinocyamus pusillus is distributed from the intertidal down to 1,250 m (Ghiold, 1982). Abra prismatic occurs in the sublittoral zone from the low-water mark down to 500 m (Oliver et al., 2016). Most Ophelia species inhabit the intertidal fringe to shallow subtidal down to depths of about 100 m (Parapar et al., 2021), Ophelia borealis has showed depth preferences shallower than 250 m (Rombouts et al., 2012)

Sensitivity assessment. This habitat occurs from 30 to 200 m and the characterizing echinoderm, polychaete and bivalve species are abundant at depths more than 200 m, suggesting these species will be tolerant of future sea-level rise. Therefore, an increase in sea-level rise is unlikely to have a large impact on this biotope and therefore resistance to sea-level rise has been assessed as ‘High’ for the middle (50 cm), and high (70 cm) emission scenario, and for the extreme scenario (107 cm). As no recovery is deemed necessary, resilience has been assessed as ‘High’, and therefore this species has been classified as ‘Not sensitive’ to sea-level rise at each of the benchmarks.

High
Low
NR
NR
Help
High
High
High
High
Help
Not sensitive
Low
NR
NR
Help
Sea level rise (middle) [Show more]

Sea level rise (middle)

Middle emission scenario benchmark: a 50 cm rise in average UK sea-level rise by the end of this century (2081-2100). Further detail.

Evidence

Sea-level rise is occurring through a combination of thermal expansion and ice melt. Sea levels have risen 1-3 mm/yr in the last century (Cazenave & Nerem, 2004, Church et al., 2004, Church & White, 2006). The most recent projections on sea-level rise suggest a rise of 50 cm under the middle emission scenario, 70 cm under the high emission scenario, and 107 cm under the extreme scenario. 

Understanding how sea-level rise will affect tidal energy, and the tide-swept nature of a habitat, is fraught with uncertainty, although evidence appears to suggest that any alterations will be non-linear (Pickering et al., 2012, Li et al., 2016). Modelling potential outcomes of sea-level rise on the tidal and residual currents in the Bohai Sea, China showed effects were site dependent, with energy either increasing or decreasing (Li et al., 2016). Similarly, Pickering et al. (2012) found a similar pattern around the UK for tidal amplitude. The effects of sea-level rise and increased wave action may be increased further due to storms and storm surges. IPCC (2019) note that the frequency of extreme sea-level events (e.g. due to storms) are predicted to increase as sea-level rises, however there is no consensus on the future storm and, hence, wave climate around UK coasts (Mossman et al., 2015; Lowe et al., 2018; Palmer et al., 2018).

The characterizing Echinocyamus pusillus is distributed from the intertidal down to 1,250 m (Ghiold, 1982). Abra prismatic occurs in the sublittoral zone from the low-water mark down to 500 m (Oliver et al., 2016). Most Ophelia species inhabit the intertidal fringe to shallow subtidal down to depths of about 100 m (Parapar et al., 2021), Ophelia borealis has showed depth preferences shallower than 250 m (Rombouts et al., 2012)

Sensitivity assessment. This habitat occurs from 30 to 200 m and the characterizing echinoderm, polychaete and bivalve species are abundant at depths more than 200 m, suggesting these species will be tolerant of future sea-level rise. Therefore, an increase in sea-level rise is unlikely to have a large impact on this biotope and therefore resistance to sea-level rise has been assessed as ‘High’ for the middle (50 cm), and high (70 cm) emission scenario, and for the extreme scenario (107 cm). As no recovery is deemed necessary, resilience has been assessed as ‘High’, and therefore this species has been classified as ‘Not sensitive’ to sea-level rise at each of the benchmarks.

High
Low
NR
NR
Help
High
High
High
High
Help
Not sensitive
Low
NR
NR
Help

Hydrological Pressures

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ResistanceResilienceSensitivity
Temperature increase (local) [Show more]

Temperature increase (local)

Benchmark. A 5°C increase in temperature for one month, or 2°C for one year. Further detail

Evidence

Davenport & Davenport (2005) demonstrated that the limits of thermal tolerance to high and low temperatures reflect distribution of intertidal macroinvertebrate species. Species that occur highest on the shore are more tolerant of a wider range of temperatures than species that occurred low on the shore or subtidally. As subtidal biotopes are less exposed to temperature fluctuations, the characterizing species may be less able to tolerate temperature fluctuations.

No direct evidence was found to support assessment of this pressure. Very few laboratory studies have been carried out on the characterizing species and the assessment relies on information on larvae in the plankton or monitoring of settlement and records of species distribution. Species from different areas may be acclimated to prevailing conditions and life histories may vary, e.g. Chamelea gallina longevity varies between populations (Gaspar et al., 2004) as does the longevity of Amphipholis squamata in different locations and habitats (Emson et al., 1989).

Kröncke et al. (1998) examined long-term changes in the macrofauna in the subtidal zone off Norderney, one of the East Frisian barrier islands. The analysis suggested that macrofauna were severely affected by cold winters whereas storms and hot summers have no impact on the benthos. A long-term increase in temperature might cause a shift in species composition. Long‐term analysis of the North Sea pelagic system has identified yearly variations in larval abundance of Echinodermata, Arthropoda, and Mollusca larvae that correlate with sea surface temperatures. Larvae of benthic echinoderms and decapod crustaceans increased after the mid‐1980s, coincident with a rise in North Sea sea surface temperature, whereas bivalve larvae underwent a reduction (Kirby et al., 2008). An increase in temperature may alter larval supply and in the long-term, and over large spatial scales, may result in changes in community composition.

Temperature cues influence the timing of gametogenesis and spawning in several species present in the biotope. Seasonal variations in reproductive cycle of Spisula solida were studied at a site off Vilamoura, southern Portugal. The onset of spawning took place in February when the seawater temperature began to increase and spawning ended in May. It is possible that Spisula solida does not spawn at a definite temperature, rather responding to the increase in seawater temperature (Gaspar & Monteiro, 1999). Many polychaete species including Mediomastus fragilis, Owenia fusiformis and Protodorvillea kefersteini also show spring/early summer recruitment (Sardá et al., 1999).

Sensitivity assessment. Little evidence was available to assess this pressure.  Assemblages in fine sands and muddy sands contain many of the characterizing species occur in the Mediterranean (see resilience section Sardá et al., 1999; Sardá et al., 2000), where temperatures are higher than experienced in the UK. It is considered likely, therefore, that a chronic change in temperature at the pressure benchmark would be tolerated by species with a wide distribution or that some species or groups of species would be resistant. An acute change may exceed thermal tolerances or lead to spawning or other biological effects. These effects may be sub-lethal or result in the removal of only a proportion of less tolerant species. Biotope resistance is therefore assessed as ‘Medium’ and resilience is assessed as ‘High’. Biotope sensitivity is therefore assessed as ‘Low’. 

Medium
High
Low
Medium
Help
High
High
Low
Medium
Help
Low
High
Low
Medium
Help
Temperature decrease (local) [Show more]

Temperature decrease (local)

Benchmark. A 5°C decrease in temperature for one month, or 2°C for one year. Further detail

Evidence

Davenport & Davenport (2005) demonstrated that the limits of thermal tolerance to high and low temperatures reflect the distribution of intertidal macroinvertebrate species. Species that occur highest on the shore are more tolerant of a wider range of temperatures than species that occurred low on the shore or subtidally. As subtidal biotopes are less exposed to temperature fluctuations the characterizing species may be less able to tolerate temperature fluctuations.

Long‐term analysis of the North Sea pelagic system has identified yearly variations in larval abundance of Echinodermata, Arthropoda, and Mollusca larvae that correlate with sea surface temperatures. Larvae of benthic echinoderms and decapod crustaceans increased after the mid‐1980s, coincident with a rise in North Sea sea surface temperature, whereas bivalve larvae underwent a reduction (Kirby et al., 2008). A decrease in temperature may alter larval supply and in the long-term, and over large spatial scales, may result in changes in community composition.

Sensitivity assessment. Many of the characterizing species are found in more northern waters than the UK and may be adapted to colder temperatures. Plankton studies suggest that colder waters may favour bivalve larvae. An acute change may exceed thermal tolerances or lead to spawning or other biological effects. These effects may be sub-lethal or remove only a proportion of less tolerant species. Biotope resistance is therefore assessed as ‘Medium’ and resilience is assessed as ‘High’. Biotope sensitivity is therefore assessed as ‘Low’. 

Medium
High
Low
Medium
Help
High
High
Low
Medium
Help
Low
High
Low
Medium
Help
Salinity increase (local) [Show more]

Salinity increase (local)

Benchmark. A increase in one MNCR salinity category above the usual range of the biotope or habitat. Further detail

Evidence

The assessed biotope occurs in full salinity (30-35 ppt) (JNCC, 2015). A change at the pressure benchmark, therefore, refers to a change to full salinity. No directly relevant evidence was found to assess this pressure. A study from the Canary Islands indicates that exposure to high salinity effluents (47- 50 psu) from desalination plants alter the structure of biological assemblages, reducing species richness and abundance (Riera et al., 2012). Bivalves and amphipods appear to be less tolerant of increased salinity than polychaetes and were largely absent at the point of discharge. Polychaetes, including species or genera that occur in this biotope, such as Spio filicornis, Glycera spp. and Lumbrineris sp., were present at the discharge point (Riera et al., 2012). The ophiuroid Amphipholis squamata has been recorded in areas of high salinity (52-55 ppt) in the Arabian Gulf (Price, 1982), indicating local acclimation may be possible.

Sensitivity assessment. High saline effluents alter the structure of biological assemblages. Polychaete species may be more tolerant than bivalves so that an increase in salinity may lead to a shift in community composition. Biotope resistance is therefore assessed as ‘Low’ and resilience as ‘Medium’, as bivalve recovery may depend on episodic recruitment. Biotope sensitivity is assessed as ‘Medium’.

Low
High
Low
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Medium
High
Low
Medium
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Medium
High
Low
Low
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Salinity decrease (local) [Show more]

Salinity decrease (local)

Benchmark. A decrease in one MNCR salinity category above the usual range of the biotope or habitat. Further detail

Evidence

Species tolerances to decreases in salinity are likely to vary but changes in sensitivity are likely to result in changes in species richness and abundance with some shift in species composition. Biotope resistance is therefore assessed as ‘Low’ and resilience as ‘Medium’, as bivalve recovery may depend on episodic recruitment. Biotope sensitivity is assessed as ‘Medium’.

Low
Low
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NR
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Medium
High
Low
Medium
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Medium
Low
Low
Low
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Water flow (tidal current) changes (local) [Show more]

Water flow (tidal current) changes (local)

Benchmark. A change in peak mean spring bed flow velocity of between 0.1 m/s to 0.2 m/s for more than one year. Further detail

Evidence

This biotope is recorded in areas where tidal flow varies between moderately strong (0.5-1,5 m/s) and weak (>0.5 m/s) (JNCC, 2015). Sands are less cohesive than mud sediments and a change in water flow at the pressure benchmark may alter sediment transport patterns within the biotope.  Hjulström (1939), concluded that fine sand (particle diameter of 0.3-0.6 mm) was easiest to erode and required a mean velocity of 0.2 m/s. Erosion and deposition of particles greater than 0.5 mm require a velocity > 0.2 m/s to alter the habitat. The topography of this habitat is shaped by currents and wave action that influence the formation of ripples in the sediment. Specific fauna may be associated with troughs and crests of these bedforms.  may form following an increase in water flow, or disappear following a reduction in flow.

Sensitivity assessment. This biotope occurs in areas subject to moderately strong water flows and these are a key factor maintaining the clean sand habitat. Changes in water flow may alter the topography of the habitat and may cause some shifts in abundance. However, a change at the pressure benchmark (increase or decrease)  is unlikely to affect biotopes that occur in mid-range flows and biotope resistance is therefore assessed as ‘High’ and resilience is assessed as ‘High’ so that the biotope is considered to be ‘Not sensitive’.

High
High
Low
NR
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High
High
High
High
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Not sensitive
Low
Low
Low
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Emergence regime changes [Show more]

Emergence regime changes

Benchmark.  1) A change in the time covered or not covered by the sea for a period of ≥1 year or 2) an increase in relative sea level or decrease in high water level for ≥1 year. Further detail

Evidence

Changes in emergence are 'Not relevant' to this biotope which is restricted to fully subtidal habitats. 

Not relevant (NR)
NR
NR
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Not relevant (NR)
NR
NR
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Not relevant (NR)
NR
NR
NR
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Wave exposure changes (local) [Show more]

Wave exposure changes (local)

Benchmark. A change in near shore significant wave height of >3% but <5% for more than one year. Further detail

Evidence

As this biotope occurs in sublittoral habitats, it is not directly exposed to the action of breaking waves. Associated polychaete species that burrow are protected within the sediment but the characterizing bivalves would be exposed to oscillatory water flows at the seabed. They and other associated species may be indirectly affected by changes in water movement where these impact the supply of food or larvae or other processes. No specific evidence was found to assess this pressure.

Sensitivity assessment. The range of wave exposures experienced by this biotpe and similar infralittoral and circalittoral biotopes is considered to indicate, by proxy, that the biotope would have ‘High’ resistance and by default ‘High’ resilience to a change in significant wave height at the pressure benchmark. The biotope is therefore classed as ‘Not sensitive’.

High
Low
NR
NR
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High
High
High
High
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Not sensitive
Low
Low
Low
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Chemical Pressures

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ResistanceResilienceSensitivity
Transition elements & organo-metal contamination [Show more]

Transition elements & organo-metal contamination

Benchmark. Exposure of marine species or habitat to one or more relevant contaminants via uncontrolled releases or incidental spills. Further detail

Evidence

This pressure is Not assessed but evidence is presented where available.

The capacity of bivalves to accumulate heavy metals in their tissues, far in excess of environmental levels, is well known. Reactions to sub-lethal levels of heavy metal stressors include siphon retraction, valve closure, inhibition of byssal thread production, disruption of burrowing behaviour, inhibition of respiration, inhibition of filtration rate, inhibition of protein synthesis and suppressed growth (see review by Aberkali & Trueman, 1985). Stirling (1975) investigated the effect of exposure to copper on Tellina tenuis. The 96 hour LC50 for Cu was 1000 µg/l. Exposure to Cu concentrations of 250 µg/l and above inhibited burrowing behaviour and would presumably result in greater vulnerability to predators. Similarly, burial of the venerid bivalve, Venerupis senegalensis, was inhibited by copper spiked sediments, and at very high concentrations, clams closed up and did not bury at all (Kaschl & Carballeira, 1999). The copper 10 day LC50 for Venerupis senegalensis was found to be 88 µg/l in sandy sediments (Kaschl & Carballeira, 1999).

Echinoderms are also regarded as being intolerant of heavy metals (e.g. Bryan, 1984; Kinne, 1984) while polychaetes are tolerant (Bryan, 1984).

Not Assessed (NA)
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Not assessed (NA)
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Not assessed (NA)
NR
NR
NR
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Hydrocarbon & PAH contamination [Show more]

Hydrocarbon & PAH contamination

Benchmark. Exposure of marine species or habitat to one or more relevant contaminants via uncontrolled releases or incidental spills. Further detail

Evidence

This pressure is Not assessed but evidence is presented where available.

Suchanek (1993) reviewed the effects of oil on bivalves. Generally, contact with oil causes an increase in energy expenditure and a decrease in feeding rate, resulting in less energy available for growth and reproduction. Sublethal concentrations of hydrocarbons also reduce byssal thread production (thus weakening attachment) and infaunal burrowing rates. Conan (1982) investigated the long-term effects of the Amoco Cadiz oil spill at St Efflam beach in France. It was estimated that the delayed mortality effects on sand and mud biotas were 1.4 times as large as the immediate effects. Fabulina fabula (studied as Tellina fabula) started to disappear from the intertidal zone a few months after the spill and from then on was restricted to subtidal levels. In the following 2 years, recruitment of Fabulina fabula was very much reduced. The author commented that, in the long-term, the biotas most severely affected by oil spills are low energy sandy and muddy shores, bays and estuaries. In such places, populations of species with long and short-term life expectancies (e.g. Fabulina fabula, Echinocardium cordatum and Ampelisca sp.) either vanished or displayed long-term decline following the Amoco Cadiz oil spill. Polychaetes, however, including Nephtys hombergii, cirratulids and capitellids were largely unaffected.

Dauvin (1998) reported the effects of the Amoco Cadiz spill on the fine sand community in the Bay of Morlaix. Reductions in abundance, biomass and production of the community were very evident through the disappearance of the dominant populations of the amphipods Ampelisca sp. which are very intolerant of oil contamination. 2 weeks after the spill, the level of hydrocarbons in subtidal sediments reached 200 ppm (Dauvin, 1984; cited in Poggiale & Dauvin, 2001). This caused the disappearance of the Ampelisca populations, leaving behind a single species, Ampelisca sarsi, in very low densities. The sediment rapidly depolluted and in 1981 benthic recruitment occurred in normal conditions (Dauvin, 1998). However, the recovery of the Ampelisca populations took up to 15 years. This was probably due to the amphipods' low fecundity, lack of pelagic larvae and the absence of local unperturbed source populations (Poggiale & Dauvin, 2001).

Echinoderms also seem to be especially intolerant of the toxic effects of oil, probably because of the large amount of exposed epidermis (Suchanek, 1993). The high intolerance of Echinocardium cordatum to hydrocarbons was seen by the mass mortality of animals, down to about 20m depth, shortly after the Amoco Cadiz oil spill (Cabioch et al., 1978).

Dauvin (2000) The muddy fine sand Abra alba-Melinna palmata community from the Bay of Morlaix (western English Channel) was strongly polluted by hydrocarbons from the Amoco Cadiz oil spill in April 1978. Long-term changes of this community (1977-1996) showed that it was weakly affected by the spill. This was due to the low number and low abundance of sensitive species present on the community in normal conditions. Polychaetes, such as Chaetozone setosa dominated the community, supporting high levels of organic matter. Only two opportunistic polychaetes Mediomastus fragilis and Tharyx marioni increased in abundance just after the spill.

Glycera spp. were described by Hiscock et al. (2004; 2005, from Levell et al., 1989) as a very tolerant taxa, found in enhanced abundances in the transitional zone along hydrocarbon contamination gradients surrounding oil platforms.

The Braer oil spill in Shetland in 1993 provided an opportunity to identify species that increased or declined in abundance where oiling occurred. Severe weather conditions meant that oil was incorporated into sediments. Kingston et al. (1995) noted that the congener Lumbrineris gracilis (from Hiscock et al. 2004) declined at oiled sites.

Diaz-Castaneda et al. (1989) looked at colonization of defaunated and polluted sediments in Dunkerque harbour. The sediment was polluted with both heavy metals and oil. Capitella capitata was generally the first polychaete to colonize the polluted sediment. Spio filicornis took between 7 weeks and 3 months to appear in the sediment suggesting it is tolerant of oil pollution.

Not Assessed (NA)
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NR
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Not assessed (NA)
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Not assessed (NA)
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Synthetic compound contamination [Show more]

Synthetic compound contamination

Benchmark. Exposure of marine species or habitat to one or more relevant contaminants via uncontrolled releases or incidental spills. Further detail

Evidence

This pressure is Not assessed but evidence is presented where available.

Stirling (1975) investigated the effects of phenol, a non-persistent, semi-synthetic organic pollutant, on Tellina tenuis. Exposure to phenol produced a measurable effect on burrowing at all concentrations tested, i.e. 50 mg/l and stronger. Sub-lethal effects of exposure to phenol included delayed burrowing and valve adduction to exclude the pollutant from the mantle cavity. After exposure to 100 mg/l for 24 hours, the majority of animals were extended from their shells and unresponsive to tactile stimulation. Following replacement of the phenol solution with clean seawater, good recovery was exhibited after 2 days for animals exposed to 50 mg/l and some recovery occurred after 4 days for animals exposed to 100 mg/l.

Similarly, no evidence was found directly relating to the effects of synthetic chemicals on Magelona mirabilis. However, there is evidence from other polychaete species. Collier & Pinn (1998) investigated the effect on the benthos of ivermectin, a feed additive treatment for infestations of sea-lice on farmed salmonids. The polychaete Hediste diversicolor was particularly susceptible, exhibiting 100% mortality within 14 days when exposed to 8 mg/m² of ivermectin in a microcosm. Arenicola marina was also intolerant of ivermectin through the ingestion of contaminated sediment (Thain et al., 1998; cited in Collier & Pinn, 1998) and it was suggested that deposit feeding was an important route for exposure to toxins. Beaumont et al. (1989) investigated the effects of tri-butyl tin (TBT) on benthic organisms. At concentrations of 1-3 µg/l there was no significant effect on the abundance of Hediste diversicolor after 9 weeks in a microcosm. However, no juvenile polychaetes were retrieved from the substratum and hence there is some evidence that TBT had an effect on the larval and/or juvenile stages.

Not Assessed (NA)
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Not assessed (NA)
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Not assessed (NA)
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Radionuclide contamination [Show more]

Radionuclide contamination

Benchmark. An increase in 10µGy/h above background levels. Further detail

Evidence

No evidence.

No evidence (NEv)
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No evidence (NEv)
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No evidence (NEv)
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Introduction of other substances [Show more]

Introduction of other substances

Benchmark. Exposure of marine species or habitat to one or more relevant contaminants via uncontrolled releases or incidental spills. Further detail

Evidence

This pressure is Not assessed.

Not Assessed (NA)
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Not assessed (NA)
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Not assessed (NA)
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De-oxygenation [Show more]

De-oxygenation

Benchmark. Exposure to dissolved oxygen concentration of less than or equal to 2 mg/l for one week (a change from WFD poor status to bad status). Further detail

Evidence

Riedel et al. (2012) assessed the response of benthic macrofauna to hypoxia advancing to anoxia in the Mediterranean. The hypoxic and anoxic conditions were created for 3-4 days in a box that enclosed in-situ sediments. In general molluscs were more resistant than polychaetes, with 90% surviving hypoxia and anoxia, whereas only 10% of polychaetes survived. Exposed individual Timoclea ovata and Tellina serrata survived the experiment but the exposed Glycera spp. died. In general epifauna were more sensitive than infauna, mobile species more sensitive than sedentary species and predatory species more sensitive than suspension and deposit feeders. The test conditions did not lead to the production of hydrogen sulphide which may have reduced mortalities compared to some observations.

Further evidence of sensitivity was available for some of the polychaete species associated with this biotope. Rabalais et al. (2001) observed that hypoxic conditions in the north Coast of the Gulf of Mexico (oxygen concentrations from 1.5 to 1 mg/l (1 to 0.7 ml/l) led to the emergence of  Lumbrineris sp. from the substrate these then lie motionless on the surface. Glycera alba was found to be able to tolerate periods of anoxia resulting from inputs of organic rich material from a wood pulp and paper mill in Loch Eil (Scotland) (Blackstock & Barnes, 1982). Niermann et al. (1990) reported changes in a fine sand community for the German Bight in an area with regular seasonal hypoxia. In 1983, oxygen levels were exceptionally low (<3 mg O2/l) in large areas and <1 mg O2/l in some areas. Species richness decreased by 30-50% and overall biomass fell. Owenia fusiformis were reduced in abundance significantly by the hypoxia Spiophanes bombyx was found in small numbers at some, but not all areas, during the period of hypoxia. Once oxygen levels returned to normal Spiophanes bombyx increased in abundance; the evidence suggests that at least some individuals would survive hypoxic conditions. 

Sensitivity assessment. Riedel et al. (2012) provide evidence on general sensitivity trends. The characterizing bivalves are likely to survive hypoxia at the pressure benchmark although the polychaetes present, particularly the mobile predatory species such as Glycera and Nephtys may be less tolerant.  As the biotope is characterized by bivalves and polychaetes, resistance is assessed as ‘Low’ and resilience as ‘High’ based on migration, water transport of adults and recolonization by pelagic larvae. Biotope sensitivity is assessed as ‘Low’.

Low
High
Medium
NR
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High
High
Low
Medium
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Low
High
Low
Low
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Nutrient enrichment [Show more]

Nutrient enrichment

Benchmark. Compliance with WFD criteria for good status. Further detail

Evidence

This pressure relates to increased levels of nitrogen, phosphorus and silicon in the marine environment compared to background concentrations. Bivalves, polychaetes and other invertebrate species are unlikely to be directly affected by changes in nutrient enrichment. As this biotope is structured by the sediments and water flow rather than nutrient enrichment and is not characterized by macroalgae (although some may be present), the biotope is probably resistant of nutrient enrichment. Nevertheless the biotope is 'Not sensitive' at the pressure benchmark of compliance with good status as defined by the WFD.

Not relevant (NR)
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Not relevant (NR)
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Not sensitive
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Organic enrichment [Show more]

Organic enrichment

Benchmark. A deposit of 100 gC/m2/yr. Further detail

Evidence

At the pressure benchmark, organic inputs are likely to represent a food subsidy for the associated deposit feeding species and are unlikely to significantly affect the structure of the biological assemblage or impact the physical habitat. Biotope sensitivity is therefore assessed as ‘High’ and resilience as ‘High’ (by default), and the biotope is therefore considered to be ‘Not sensitive’.

High
Low
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High
High
High
High
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Not sensitive
Low
Low
Low
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Physical Pressures

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ResistanceResilienceSensitivity
Physical loss (to land or freshwater habitat) [Show more]

Physical loss (to land or freshwater habitat)

Benchmark. A permanent loss of existing saline habitat within the site. Further detail

Evidence

All marine habitats and benthic species are considered to have a resistance of ‘None’ to this pressure and to be unable to recover from a permanent loss of habitat (resilience is ‘Very Low’). Sensitivity within the direct spatial footprint of this pressure is therefore ‘High’. Although no specific evidence is described, confidence in this assessment is ‘High’ due to the incontrovertible nature of this pressure.

None
High
High
High
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Very Low
High
High
High
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High
High
High
High
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Physical change (to another seabed type) [Show more]

Physical change (to another seabed type)

Benchmark. Permanent change from sedimentary or soft rock substrata to hard rock or artificial substrata or vice-versa. Further detail

Evidence

The biotope is characterized by the sedimentary habitat (JNCC, 2015), so a change to an artificial or rock substratum would alter the character of the biotope leading to reclassification and the loss of the sedimentary community including the characterizing bivalves, polychaetes and echinoderms that live buried within the sediment.

Sensitivity assessment. Based on the loss of the biotope, resistance is assessed as ‘None’, recovery is assessed as ‘Very Low’ (as the change at the pressure benchmark is permanent), and sensitivity is assessed as ‘High’.

None
High
High
High
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Very Low
High
High
High
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High
High
High
High
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Physical change (to another sediment type) [Show more]

Physical change (to another sediment type)

Benchmark. Permanent change in one Folk class (based on UK SeaMap simplified classification). Further detail

Evidence

This biotope is found in medium to very fine sand (JNCC, 2022). The change referred to at the pressure benchmark is a change in sediment classification based on Long (2006).  For sand sediments, resistance is assessed based on a change to either mixed sediments or mud and sandy muds. Sediment type is a key factor structuring the biological assemblage present in the biotope. Surveys over sediment gradients and before-and-after impact studies from aggregate extraction sites where sediments have been altered indicate patterns in change. The biotope classification (JNCC, 2015, 2022) provides information on the sediment types where biotopes are found and indicates likely patterns in change if the sediment were to alter.  

Differences in biotope assemblages in areas of different sediment type are likely to be driven by pre and post recruitment processes. Sediment selectivity by larvae will influence levels of settlement and distribution patterns. Snelgrove et al. (1999) demonstrated that Spisula solidissima, selected coarse sand over muddy sand, and capitellid polychaetes selected muddy sand over coarse sand, regardless of site. Both larvae selected sediments typical of adult habitats, however, some species were nonselective (Snelgrove et al., 1999) and presumably in unfavourable habitats post recruitment, mortality will result for species that occur in a restricted range of habitats. Some species may, however, be present in a range of sediments. Post-settlement migration and selectivity also occurred on small scales (Snelgrove et al., 1999).

Cooper et al. (2011) found that characterizing species from sand dominated sediments were equally likely to be found in gravel dominated sediments. Hence, an increase in sediment coarseness (due to an increase in gravel) may not result in loss of characterizing species as is shown in the variant from of this biotope (JNCC, 2022). However, a significant increase in gravel may casue th biotope to transition to SS.SCS.CCS.Blan or SS.SCS.CCS.MedLumVen, which occur in gravels (JNCC, 2022).

Desprez (2000) found that a change of habitat to fine sands from coarse sands and gravels (from deposition of screened sand following aggregate extraction) changed the biological communities present. Tellina pygmaea and Nephtys cirrosa dominated the fine sand community. Dominant species of coarse sands, Echinocyamus pusillus and Amphipholis squamata, were poorly represented and the characteristic species of gravels and shingles were absent (Desprez, 2000).

Sensitivity assessment.  A change to finer, muddy likely to reduce the abundance of the characterizing Tellina spp., venerid bivalves and other bivalves such as Spisula solida, and favour polychaetes, resulting in the loss of this biotope.  A change to more mixed, gravel-dominated sediments, may not affect the presence of the characterstic species but would alter the biotope classification. Therefore, biotope resistance is assessed as ‘Low’ (as some species may remain), resilience as 'Very low' (the pressure is a permanent change) and sensitivity is assessed as 'High'.

Low
High
High
High
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Very Low
High
High
High
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High
High
Low
Medium
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Habitat structure changes - removal of substratum (extraction) [Show more]

Habitat structure changes - removal of substratum (extraction)

Benchmark. The extraction of substratum to 30 cm (where substratum includes sediments and soft rock but excludes hard bedrock). Further detail

Evidence

Most of the animals that occur in this biotope are shallowly buried and extraction of the sediment will remove the biological assemblage.

Sensitivity assessment. Resistance is assessed as ‘None’ as extraction of the sediment swill remove the characterizing and associated species present. Resilience is assessed as ‘Medium’ as some species may require longer than two years to re-establish (see resilience section) and sediments may need to recover (where exposed layers are different). Biotope sensitivity is therefore assessed as ‘Medium’.

None
High
High
High
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Medium
High
Low
Medium
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Medium
High
High
High
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Abrasion / disturbance of the surface of the substratum or seabed [Show more]

Abrasion / disturbance of the surface of the substratum or seabed

Benchmark. Damage to surface features (e.g. species and physical structures within the habitat). Further detail

Evidence

Abrasion is likely to damage epifauna and flora and may damage a proportion of the characterizing species, biotope resistance is therefore assessed as ‘Medium’. Resilience is assessed as ‘High’ as opportunistic species are likely to recruit rapidly and some damaged characterizing species may recover or recolonize. Biotope sensitivity is assessed as ‘Low’.

Medium
Low
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High
High
Low
Medium
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Low
Low
Low
Low
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Penetration or disturbance of the substratum subsurface [Show more]

Penetration or disturbance of the substratum subsurface

Benchmark. Damage to sub-surface features (e.g. species and physical structures within the habitat). Further detail

Evidence

The epifauna and infaunal assemblages of both stable and dynamic fine sands are susceptible to direct physical disturbance from towed demersal gears and dredges which penetrate and disturb the sediment e.g. Eleftheriou & Robertson, 1992; Kaiser et al., 1998; Robinson & Richardson, 1998; Schwinghamer et al., 1996; Freese et al., 1999; Prena et al,. 1999; Bergman & Van Santbrick 2000a,b; Tuck et al., 2000; Kenchington et al., 2001; Gilkinson et al., 2005). In general, fishing using towed gears results in the mortality of non-target organisms either through physical damage inflicted by the passage of the trawl or indirectly by disturbance, damage, exposure and subsequent predation. Beam trawling, for example, decreases the density of common echinoderms, polychaetes and molluscs (Bergman & Hup, 1992) and decreases the density and diversity of epifauna in stable sand habitats (Kaiser & Spencer, 1996).

Gilkinson et al. (1998) simulated the physical interaction of otter trawl doors with the seabed in a laboratory test tank using a full-scale otter trawl door model. Between 58% and 70% of the bivalves in the scour path that were originally buried were completely or partially exposed at the test bed surface. However, only two out of a total of 42 specimens showed major damage. The pressure wave associated with the otter door pushes small bivalves out of the way without damaging them. Where species can rapidly burrow and reposition (typically within species occurring in unstable habitats) before predation mortality rates will be relatively low. These experimental observations are supported by diver observations of fauna dislodged by a hydraulic dredge used to catch Ensis spp. Small bivalves were found in the trawl tracks that had been dislodged from the sediments, including the venerid bivalves Dosinia exoleta, Chamelea striatula and the hatchet shell Lucinoma borealis. These were usually intact (Hauton et al., 2003a) and could potentially reburrow.

Larger, fragile species are more likely to be damaged by sediment penetration and disturbance than smaller species (Tillin et al., 2006). Bergman & van Santbrink (2000) suggested that the megafauna were amongst the species most vulnerable to direct mortality due to bottom trawling in sandy sediments. Stomach analysis of fish caught scavenging in the tracks of beam trawls found parts of Spatangus purpureus and Ensis spp. indicating that these had been damaged and exposed by the trawl (Kaiser & Spencer, 1994a). Capasso et al. (2010) compared benthic survey datasets from 1895 and 2007 for an area in the English Channel. Although methodological differences limit direct comparison, the datasets appear to show that large, fragile urchin species including Echinus esculentus, Spatangus purpureus and Psammechinus miliaris and larger bivalves had decreased in abundance. Small, mobile species such as amphipods and small errant and predatory polychaetes (Nephtys, Glycera, Lumbrineris) appeared to have increased (Capasso et al., 2010). The area is subject to beam trawling and scallop dredging and the observed species changes would correspond with predicted changes following physical disturbance. Two small species: Timoclea ovata and Echinocyamus pusillus had increased in abundance between the two periods.

Sensitivity assessment. The trawling studies and the comparative study by Capasso et al. (2010) suggest that the biological assemblage present in this biotope is characterized by species that are relatively tolerant of penetration and disturbance of the sediments. Either species are robust or buried within sediments or are adapted to habitats with frequent disturbance (natural or anthropogenic) and recover quickly. The results suggest that a reduction in physical disturbance may lead to the development of a community with larger, more fragile species including large bivalves. Biotope resistance is assessed as ‘Medium’ as some species will be displaced and may be predated or injured and killed. Biotope resilience is assessed as ‘High’ as most species will recover rapidly and the biotope is likely to still be classified as the same type following disturbance. Biotope sensitivity is therefore assessed as ‘Low’.

Medium
High
High
Medium
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High
High
Medium
High
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Low
High
High
Medium
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Changes in suspended solids (water clarity) [Show more]

Changes in suspended solids (water clarity)

Benchmark. A change in one rank on the WFD (Water Framework Directive) scale e.g. from clear to intermediate for one year. Further detail

Evidence

A change in turbidity at the pressure benchmark is assessed as an increase from intermediate 10-100 mg/l to medium (100-300 mg/l) and a change to clear (<10 mg/l). An increase or decrease in turbidity may affect primary production in the water column and indirectly alter the availability of phytoplankton food available to species in filter feeding mode. However, phytoplankton will also be transported from distant areas and so the effect of increased turbidity may be mitigated to some extent.  According to Widdows et al. (1979), growth of filter-feeding bivalves may be impaired at suspended particulate matter (SPM) concentrations >250 mg/l.

Sensitivity assessment. No direct evidence was found to assess impacts on the characterizing and associated species. The characterizing, suspension feeding bivalves  are not predicted to be sensitive to decreases in turbidity and may be exposed to, and tolerant of, short-term increases in turbidity following sediment mobilization by storms and other events. An increase in suspended solids, at the pressure benchmark may have negative impacts on growth and fecundity by reducing filter feeding efficiency and imposing costs on clearing. Biotope resistance is assessed as ‘Medium’ as there may be some shift in the structure of the biological assemblage and resilience is assessed as ‘High’ (following restoration of typical conditions). Biotope sensitivity is assessed as ‘Low’.

Medium
Low
NR
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High
High
Low
Medium
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Low
Low
Low
Low
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Smothering and siltation rate changes (light) [Show more]

Smothering and siltation rate changes (light)

Benchmark. ‘Light’ deposition of up to 5 cm of fine material added to the seabed in a single discrete event. Further detail

Evidence

Addition of fine material will alter the character of this habitat by covering it with a layer of dissimilar sediment and will reduce suitability for the species associated with this feature. Recovery will depend on the rate of sediment mixing or removal of the overburden, either naturally or through human activities. Recovery to a recognisable form of the original biotope will not take place until this has happened. In areas where the local hydrodynamic conditions are unaffected, fine particles will be removed by wave action moderating the impact of this pressure. The rate of habitat restoration would be site-specific and would be influenced by the type of siltation and rate. Long-term or permanent addition of fine particles would lead to re-classification of this biotope type (see physical change pressures). The additions of silts to a Spisula solida bed in Waterford Harbour (Republic of Ireland) from earthworks further upstream, for example, reduced the extent of the bed (Fahy et al., 2003). No information was provided on the depth of any deposits.

Most bivalve species are capable of burrowing through sediment to feed, e.g. Abra alba are capable of upwardly migrating if lightly buried by additional sediment (Schafer, 1972). There may be an energetic cost expended by species to either re-establish burrow openings, to self-clean feeding apparatus or to move up through the sediment, though this is not likely to be significant. Most animals will be able to reburrow or move up through the sediment within hours or days. Bijkerk (1988, results cited from Essink, 1999) indicated that the maximal overburden through which small bivalves could migrate was 20 cm in sand for Donax and approximately 40 cm in mud for Tellina sp. and approximately 50 cm in sand.  No further information was available on the rates of survivorship or the time taken to reach the surface. Little direct evidence was found to assess the impact of this pressure at the benchmark level.  Powilleit et al. (2009) studied the response of the polychaete Nephtys hombergii to smothering. This species successfully migrated to the surface of 32-41 cm deposited sediment layer of till or sand/till mixture and restored contact with the overlying water. The high escape potential could partly be explained by the heterogeneous texture of the till and sand/till mixture with ‘voids’. While crawling upward to the new sediment surfaces burrowing velocities of up to 20 cm/day were recorded for Nephtys hombergii. Similarly, Bijkerk (1988, results cited from Essink 1999) indicated that the maximal overburden through which species could migrate was 60 cm through mud for Nephtys and 90 cm through sand. No further information was available on the rates of survivorship or the time taken to reach the surface.

Sensitivity assessment. Bivalves and polychaetes and other species are likely to be able to survive short periods under sediments and to reposition. However, as the pressure benchmark refers to fine material, this may be cohesive and species characteristic of sandy habitats may be less adapted to move through this than sands. Biotope resistance is assessed as 'Medium' as some mortality of characterizing and associated species may occur. Biotope resilience is assessed as 'High' and biotope sensitivity is assessed as 'Low'. 

Medium
High
Medium
Medium
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High
High
Low
Medium
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Low
High
Low
Medium
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Smothering and siltation rate changes (heavy) [Show more]

Smothering and siltation rate changes (heavy)

Benchmark. ‘Heavy’ deposition of up to 30 cm of fine material added to the seabed in a single discrete event. Further detail

Evidence

Bijkerk (1988, results cited from Essink, 1999) indicated that the maximal overburden through which small bivalves could migrate was 20 cm in sand for Donax and approximately 40 cm in mud for Tellina sp. and approximately 50 cm in sand. No further information was available on the rates of survivorship or the time taken to reach the surface.

Sensitivity assessment. The character of the overburden is an important factor determining the degree of vertical migration of buried bivalves. Individuals are more likely to escape from a covering similar to the sediments in which the species is found than a different type. Resistance is assessed as ‘Low’ as few individuals are likely to reposition.  Resilience is assessed as ‘Medium’ and sensitivity is assessed as ‘Medium’.

Low
High
Medium
NR
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Medium
High
Low
Medium
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Medium
High
Low
Low
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Litter [Show more]

Litter

Benchmark. The introduction of man-made objects able to cause physical harm (surface, water column, seafloor or strandline). Further detail

Evidence

Not assessed.

Not Assessed (NA)
NR
NR
NR
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Not assessed (NA)
NR
NR
NR
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Not assessed (NA)
NR
NR
NR
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Electromagnetic changes [Show more]

Electromagnetic changes

Benchmark. A local electric field of 1 V/m or a local magnetic field of 10 µT. Further detail

Evidence

No evidence.

No evidence (NEv)
NR
NR
NR
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No evidence (NEv)
NR
NR
NR
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No evidence (NEv)
NR
NR
NR
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Underwater noise changes [Show more]

Underwater noise changes

Benchmark. MSFD indicator levels (SEL or peak SPL) exceeded for 20% of days in a calendar year. Further detail

Evidence

Not relevant. No information was found concerning the intolerance of the biotope or the characterizing species to noise. The siphons of bivalves and palps of polychaetes are likely to detect vibrations and are probably withdrawn as a predator avoidance mechanism. However, it is unlikely that the biotope will be affected by noise or vibrations caused by noise at the level of the benchmark.

Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Introduction of light or shading [Show more]

Introduction of light or shading

Benchmark. A change in incident light via anthropogenic means. Further detail

Evidence

Not relevant.

Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Barrier to species movement [Show more]

Barrier to species movement

Benchmark. A permanent or temporary barrier to species movement over ≥50% of water body width or a 10% change in tidal excursion. Further detail

Evidence

Not relevant.

Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Death or injury by collision [Show more]

Death or injury by collision

Benchmark. Injury or mortality from collisions of biota with both static or moving structures due to 0.1% of tidal volume on an average tide, passing through an artificial structure. Further detail

Evidence

Not relevant’ to seabed habitats.  NB. Collision by grounding vessels is addressed under ‘surface abrasion.

Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Visual disturbance [Show more]

Visual disturbance

Benchmark. The daily duration of transient visual cues exceeds 10% of the period of site occupancy by the feature. Further detail

Evidence

Not relevant.

Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Biological Pressures

Use [show more] / [show less] to open/close text displayed

ResistanceResilienceSensitivity
Genetic modification & translocation of indigenous species [Show more]

Genetic modification & translocation of indigenous species

Benchmark. Translocation of indigenous species or the introduction of genetically modified or genetically different populations of indigenous species that may result in changes in the genetic structure of local populations, hybridization, or change in community structure. Further detail

Evidence

Key characterizing species within this biotope are not cultivated or translocated. This pressure is therefore considered ‘Not relevant’ to this biotope group.

Not relevant (NR)
NR
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Not relevant (NR)
NR
NR
NR
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Not relevant (NR)
NR
NR
NR
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Introduction or spread of invasive non-indigenous species [Show more]

Introduction or spread of invasive non-indigenous species

Benchmark. The introduction of one or more invasive non-indigenous species (INIS). Further detail

Evidence

Few invasive non-indigenous species may be able to colonize mobile sands, due to the high-levels of sediment disturbance. However, two species may be of concern. The slipper limpet Crepidula fornicata may settle on stones in substrates and hard surfaces such as bivalve shells and can sometimes form dense carpets which can smother bivalves and alter the seabed, making the habitat unsuitable for larval settlement. Dense aggregations trap suspended silt, faeces and pseudofaeces altering the benthic habitat. Where slipper limpet stacks are abundant, few other bivalves can live amongst them (Fretter & Graham, 1981; Blanchard, 1997). Muddy and mixed sediments in wave sheltered areas are probably optimal but Crepidula fornicata has been recorded from a wide variety of habitats including clean sands and areas subject to moderately strong tidal streams (Blanchard, 1997; De Montaudouin & Sauriau, 1999).  Bohn et al. (2015) report that in the Milford Haven Waterway (MHW) in southwest Wales, UK, subtidally, highest densities were found in areas of high gravel content (grain sizes 16-256 mm), suggesting that the availability of this substrata type is beneficial for its establishment.

The colonial ascidian Didemnum vexillum is present in the UK but appears to be restricted to artificial surfaces such as pontoons, this species may, however, have the potential to colonize and smother offshore gravel habitats. Valentine et al., (2007) describe how Didemnum sp. appear to have rapidly colonized gravel areas on the Georges Bank (US/Canada boundary). Colonies can coalesce to form large mats that may cover more than 50% of the seabed in parts. Areas of mobile sand bordered communities of Didemnum sp. and these therefore do not appear to be suitable habitats (Valentine et al., 2007).

Although not currently established in UK waters, the whelk Rapana venosa, may spread to UK habitats from Europe. Both Rapana venosa and the introduced oyster drill Urosalpinx cinerea both predate on bivalves and could therefore negatively affect the characterizing bivalve species.

Sensitivity assessment. The sediments characterizing this biotope are likely to too mobile or otherwise unsuitable for most of the recorded invasive non-indigenous species currently recorded in the UK. The slipper limpet may colonize this habitat resulting in habitat change and potentially classification to the biotope which is found in similar habitats SS.SMx.IMx.CreAsAn. Didemnum sp. and non-native predatory gastropods may also emerge as a threat to this biotope, although more mobile sands may exclude Didemnum. Based on Crepidula fornicata biotope resistance is assessed as ‘None’ and resilience as ‘Very low’ (as removal of established non-native is unlikely), so that biotope sensitivity is assessed as ‘High’.

None
Low
NR
NR
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Very Low
Low
NR
NR
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High
Low
Low
Low
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Introduction of microbial pathogens [Show more]

Introduction of microbial pathogens

Benchmark. The introduction of relevant microbial pathogens or metazoan disease vectors to an area where they are currently not present (e.g. Martelia refringens and Bonamia, Avian influenza virus, viral Haemorrhagic Septicaemia virus). Further detail

Evidence

No evidence was found for the characterizing polychaete species. Populations of bivalve species may be subject to a variety of diseases and parasites but evidence for the characterizing bivalves is limited. Berilli et al. (2000) conducted a parasitological survey of the bivalve Chamelea gallina in natural beds of the Adriatic Sea, where anomalous mortalities had been observed in 1997-1999. The occurrence of protozoans belonging to the families Porosporidae, Hemispeiridae and Trichodinidae was recorded. Porosporidae of the genus Nematopsis, present with 4 species, showed a prevalence of 100%. The results suggested that severe infections of protozoans of the genus Nematopsis could cause a not negligible respiratory sufferance, with a possible role in the decline of the natural banks of Chamelea gallina (Berilli et al., 2000).

Bacterial diseases are frequently found in molluscs during their larval stages, but seem to be relatively insignificant in populations of adult animals (Lόpez-Flores et al., 2004). This may be due to the primary defence mechanisms of molluscs, phagocytosis and encapsulation, which fight against small-sized pathogens, and whose resistance may be age related (Sinderman, 1990; Lόpez-Flores et al., 2004).

Individuals of Fabulina fabula from Boulogne-sur-Mer (studied as Angulus fabula) were infected with the trematode parasite Gymnophallus strigatus, causing erosion of the shell (Giard, 1897, cited in Kinne, 1983).

Sensitivity assessments. Pathogens may cause mortality and there may be a minor decline in species richness or abundance in the biotope. As there is no evidence for mass mortalities of characterizing species that would alter biotope classification biotope resistance is assessed as ‘Medium’. Biotope resilience is assessed as ‘High’ as changes may fall within natural population variability and a recognizable biotope is likely to be present after two years. Biotope sensitivity is therefore assessed as ‘Low’.

Medium
High
High
High
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High
High
Low
Medium
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Low
High
Low
Medium
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Removal of target species [Show more]

Removal of target species

Benchmark. Removal of species targeted by fishery, shellfishery or harvesting at a commercial or recreational scale. Further detail

Evidence

A number of the larger bivalve species that may be associated with this biotope group are targeted by commercial fishers in some parts of their range. These include Chamelea gallina (Ballarin et al., 2003); Spisula solida (Fahy et al., 2003; Joaquim et al., 2008); Glycymeris glycymeris and Paphia spp. (Savina & Pouvreau, 2004); Ensis spp., Donax spp. and Pharus spp. (Chícharo et al., 2002). In targeted areas, the populations of fished bivalves may be depleted, for example, fishing has led to declines in Spisula solida (Joaquim et al., 2008; Fahy et al., 2003).

Sensitivity assessment. In general dredges that are used to target bivalves are likely to be efficient at removing targeted species. Removal of commercially targeted bivalves may lead to biotope reclassification based on the dominance of polychaetes to a similar biotope Biotope resistance, based on the characterizing bivalves is assessed as ‘Low’. Undersized juveniles may be returned and can re-burrow but are likely to suffer from stress. Targeted removal of adult bivalves within the biotope may allow successful recruitment of juveniles where intra-specific competition for space and food and possibly consumption of larvae has prevented successful spatfall. Some species such as Glycymeris glycymeris are characteristic of habitats with low levels of competition and may benefit from removal of other species. Biotope resilience is assessed as ‘Medium’, as recruitment in many bivalve species is episodic and unpredictable. Biotope sensitivity is therefore assessed as ‘Medium’.

Low
Low
NR
NR
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Medium
High
Low
Medium
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Medium
Low
Low
Low
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Removal of non-target species [Show more]

Removal of non-target species

Benchmark. Removal of features or incidental non-targeted catch (by-catch) through targeted fishery, shellfishery or harvesting at a commercial or recreational scale. Further detail

Evidence

Species within the biotope are not functionally dependent on each other, although biological interactions will play a role in structuring the biological assemblage through predation and competition. Removal of adults may support recruitment of juvenile bivalves by reducing competition for space and consumption of larvae. Removal of species would also reduce the ecological services provided by these species such as secondary production and nutrient cycling.

Sensitivity assessment. Species within the biotope are relatively sedentary or slow moving, although the infaunal position may protect some burrowing species from removal. Biotope resistance is therefore assessed as ‘Low’ and resilience as ‘High’, as the habitat is likely to be directly affected by removal and some species will recolonize rapidly, biotope sensitivity is therefore assessed as Low'. Some variability in species recruitment, abundance and composition is natural and therefore a return to a recognizable biotope should occur within 2 years. Repeated chronic removal would, however, impact recovery.

Low
Low
NR
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High
High
Low
Medium
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Low
Low
Low
Low
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Bibliography

  1. Aberkali, H.B. & Trueman, E.R., 1985. Effects of environmental stress on marine bivalve molluscs. Advances in Marine Biology, 22, 101-198.

  2. Ansell, A.D., Barnett, P.R.O., Bodoy, A. & Masse, H., 1980. Upper temperature tolerances of some European molluscs. 1. Tellina fabula and T. tenuis. Marine Biology, 58, 33-39.

  3. Asnaghi, Valentina, Mangialajo, Luisa, Gattuso, Jean-Pierre, Francour, Patrice, Privitera, Davide & Chiantore, Mariachiara, 2014. Effects of ocean acidification and diet on thickness and carbonate elemental composition of the test of juvenile sea urchins. Marine Environmental Research, 93, 78-84. DOI https://doi.org/10.1016/j.marenvres.2013.08.005

  4. Asnicar, Davide & Marin, Maria Gabriella, 2022. Effects of Seawater Acidification on Echinoid Adult Stage: A Review. Journal of Marine Science and Engineering, 10 (4), 477. DOI https://doi.org/10.3390/jmse10040477

  5. Ballarin, L., Pampanin, D.M. & Marin, M.G., 2003. Mechanical disturbance affects haemocyte functionality in the Venus clam Chamelea gallina. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 136 (3), 631-640.

  6. Barnes, R.S.K. & Hughes, R.N., 1992. An introduction to marine ecology. Oxford: Blackwell Scientific Publications.

  7. Beaumont, A.R., Newman, P.B., Mills, D.K., Waldock, M.J., Miller, D. & Waite, M.E., 1989. Sandy-substrate microcosm studies on tributyl tin (TBT) toxicity to marine organisms. Scientia Marina, 53, 737-743.

  8. Bergman, M.J.N. & Van Santbrink, J.W., 2000b. Fishing mortality of populations of megafauna in sandy sediments. In The effects of fishing on non-target species and habitats (ed. M.J. Kaiser & S.J de Groot), 49-68. Oxford: Blackwell Science.

  9. Bergman, M.J.N. & Van Santbrink, J.W., 2000a. Mortality in megafaunal benthic populations caused by trawl fisheries on the Dutch continental shelf in the North Sea in 1994. ICES Journal of Marine Science, 57 (5), 1321-1331.

  10. Berrilli, F., Ceschia, G., De Liberato, C., Di Cave, D. & Orecchia, P., 2000. Parasitic infections of Chamelea gallina (Mollusca, Bivalvia) from commercially exploited banks of the Adriatic Sea. Bulletin of European Association of Fish Pathologists, 20 (5), 199-205.

  11. Bijkerk, R., 1988. Ontsnappen of begraven blijven: de effecten op bodemdieren van een verhoogde sedimentatie als gevolg van baggerwerkzaamheden: literatuuronderzoek: RDD, Aquatic ecosystems.

  12. Blackstock, J. & Barnes, M., 1982. The Loch Eil project: biochemical composition of the polychaete, Glycera alba (Müller), from Loch Eil. Journal of Experimental Marine Biology and Ecology, 57 (1), 85-92.

  13. Blanchard, M., 1997. Spread of the slipper limpet Crepidula fornicata (L.1758) in Europe. Current state and consequences. Scientia Marina, 61, Supplement 9, 109-118. Available from: http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/290/

  14. Bohn, K., Richardson, C.A. & Jenkins, S.R., 2015. The distribution of the invasive non-native gastropod Crepidula fornicata in the Milford Haven Waterway, its northernmost population along the west coast of Britain. Helgoland Marine Research, 69 (4), 313.

  15. Bosselmann, A., 1989. Larval plankton and recruitment of macrofauna in a subtidal area in the German Bight. In Reproduction, Genetics and Distributions of Marine Organisms (ed. J.S. Ryland & P.A. Tyler), pp. 43-54.

  16. Boyd, S., Limpenny, D., Rees, H. & Cooper, K., 2005. The effects of marine sand and gravel extraction on the macrobenthos at a commercial dredging site (results 6 years post-dredging). ICES Journal of Marine Science: Journal du Conseil, 62 (2), 145-162.

  17. Bradshaw, C., Veale, L.O., Hill, A.S. & Brand, A.R., 2000. The effects of scallop dredging on gravelly seabed communities. In: Effects of fishing on non-target species and habitats (ed. M.J. Kaiser & de S.J. Groot), pp. 83-104. Oxford: Blackwell Science.

  18. Bryan, G.W. & Gibbs, P.E., 1991. Impact of low concentrations of tributyltin (TBT) on marine organisms: a review. In: Metal ecotoxicology: concepts and applications (ed. M.C. Newman & A.W. McIntosh), pp. 323-361. Boston: Lewis Publishers Inc.

  19. Bryan, G.W., 1984. Pollution due to heavy metals and their compounds. In Marine Ecology: A Comprehensive, Integrated Treatise on Life in the Oceans and Coastal Waters, vol. 5. Ocean Management, part 3, (ed. O. Kinne), pp.1289-1431. New York: John Wiley & Sons.

  20. Buchanan, J.B. & Moore, J.B., 1986. A broad review of variability and persistence in the Northumberland benthic fauna - 1971-85. Journal of the Marine Biological Association of the United Kingdom, 66, 641-657.

  21. Cabioch, L., Dauvin, J.C. & Gentil, F., 1978. Preliminary observations on pollution of the sea bed and disturbance of sub-littoral communities in northern Brittany by oil from the Amoco Cadiz. Marine Pollution Bulletin, 9, 303-307.

  22. Capasso, E., Jenkins, S., Frost, M. & Hinz, H., 2010. Investigation of benthic community change over a century-wide scale in the western English Channel. Journal of the Marine Biological Association of the United Kingdom, 90 (06), 1161-1172.

  23. Cazenave, A. & Nerem, R.S., 2004. Present-day sea-level change: Observations and causes. Reviews of Geophysics, 42 (3). DOI https://doi.org/10.1029/2003rg000139

  24. Chícharo, L., Chícharo, M., Gaspar, M., Regala, J. & Alves, F., 2002. Reburial time and indirect mortality of Spisula solida clams caused by dredging. Fisheries Research, 59, 247-257.

  25. Church, J.A. & White, N.J., 2006. A 20th century acceleration in global sea-level rise. Geophysical Research Letters, 33 (1). DOI https://doi.org/10.1029/2005gl024826

  26. Church, J.A., White, N.J., Coleman, R., Lambeck, K. & Mitrovica, J.X., 2004. Estimates of the Regional Distribution of Sea Level Rise over the 1950–2000 Period. Journal of Climate, 17 (13), 2609-2625.

  27. Collier, L.M. & Pinn, E.H., 1998. An assessment of the acute impact of the sea lice treatment Ivermectin on a benthic community. Journal of Experimental Marine Biology and Ecology, 230 (1), 131-147. DOI https://doi.org/10.1016/s0022-0981(98)00081-1

  28. Conan, G., 1982. The long-term effects of the Amoco Cadiz oil spill. Philosophical Transactions of the Royal Society of London B, 297, 323-333.

  29. Connor, D.W., Dalkin, M.J., Hill, T.O., Holt, R.H.F. & Sanderson, W.G., 1997a. Marine biotope classification for Britain and Ireland. Vol. 2. Sublittoral biotopes. Joint Nature Conservation Committee, Peterborough, JNCC Report no. 230, Version 97.06., Joint Nature Conservation Committee, Peterborough, JNCC Report no. 230, Version 97.06.

  30. Cooper, K., Ware, S., Vanstaen, K. & Barry, J., 2011. Gravel seeding - A suitable technique for restoring the seabed following marine aggregate dredging? Estuarine, Coastal and Shelf Science, 91 (1), 121-132.

  31. Costa, M.J. & Elliot, M., 1991. Fish usage and feeding in two industrialised estuaries - the Tagus, Portugal and the Forth, Scotland. In Estuaries and Coasts: Spatial and Temporal Intercomparisons (ed. B. Knights & A.J. Phillips), pp. 289-297. Denmark: Olsen & Olsen.

  32. Cotter, A.J.R., Walker, P., Coates, P., Cook, W. & Dare, P.J., 1997. Trial of a tractor dredger for cockles in Burry Inlet, South Wales. ICES Journal of Marine Science, 54, 72-83.

  33. Crisp, D.J. (ed.), 1964. The effects of the severe winter of 1962-63 on marine life in Britain. Journal of Animal Ecology, 33, 165-210.

  34. Dauvin, J.C., 1985. Dynamics and production of a population of Venus ovata (Pennant) (Mollusca-Bivalvia) of Morlaix Bay (western English Channel). Journal of Experimental Marine Biology and Ecology, 91, 109-123.

  35. Dauvin, J.C., 1998. The fine sand Abra alba community of the Bay of Morlaix twenty years after the Amoco Cadiz oil spill. Marine Pollution Bulletin, 36, 669-676.

  36. Dauvin, J.C., 2000. The muddy fine sand Abra alba - Melinna palmata community of the Bay of Morlaix twenty years after the Amoco Cadiz oil spill. Marine Pollution Bulletin, 40, 528-536.

  37. Davenport, J. & Davenport, J.L., 2005. Effects of shore height, wave exposure and geographical distance on thermal niche width of intertidal fauna. Marine Ecology Progress Series, 292, 41-50.

  38. David, Andrew A., 2021. Climate Change and Shell-Boring Polychaetes (Annelida: Spionidae): Current State of Knowledge and the Need for More Experimental Research. The Biological Bulletin, 241 (1), 4-15. DOI https://doi.org/10.1086/714989

  39. Davies, C.E. & Moss, D., 1998. European Union Nature Information System (EUNIS) Habitat Classification. Report to European Topic Centre on Nature Conservation from the Institute of Terrestrial Ecology, Monks Wood, Cambridgeshire. [Final draft with further revisions to marine habitats.], Brussels: European Environment Agency.

  40. De Montaudouin, X. & Sauriau, P.G., 1999. The proliferating Gastropoda Crepidula fornicata may stimulate macrozoobenthic diversity. Journal of the Marine Biological Association of the United Kingdom, 79, 1069-1077. DOI https://doi.org/10.1017/S0025315499001319

  41. Desprez, M., 2000. Physical and biological impact of marine aggregate extraction along the French coast of the Eastern English Channel: short- and long-term post-dredging restoration. ICES Journal of Marine Science, 57 (5), 1428-1438.

  42. Diaz-Castaneda, V., Richard, A. & Frontier, S., 1989. Preliminary results on colonization, recovery and succession in a polluted areas of the southern North Sea (Dunkerque's Harbour, France). Scientia Marina, 53, 705-716.

  43. Dyer, K.R., 1998. Estuaries - a Physical Introduction. John Wiley & Son, Chichester.

  44. Eleftheriou, A. & Robertson, M.R., 1992. The effects of experimental scallop dredging on the fauna and physical environment of a shallow sandy community. Netherlands Journal of Sea Research, 30, 289-299.

  45. Elliott, M., 1994. The analysis of macrobenthic community data. Marine Pollution Bulletin, 28, 62-64.

  46. Emson, R.H., Jones, M. & Whitfield, P., 1989. Habitat and latitude differences in reproductive pattern and life-history in the cosmopolitan brittle-star Amphipholis squamata (Echinodermata). In: Ryland, J.S., Tyler, P.A. (Eds.), Reproduction, Genetics and Distributions of Marine Organisms, pp. 75-81. Olsen & Olsen, Fredensborg.

  47. Eno, N.C., 1991. Marine Conservation Handbook. English Nature, Peterborough.

  48. Espinel-Velasco, N., Hoffmann, L., Agüera, A., Byrne, M., Dupont, S., Uthicke, S., Webster, N. S. & Lamare, M., 2018. Effects of ocean acidification on the settlement and metamorphosis of marine invertebrate and fish larvae: a review. Marine Ecology Progress Series, 606, 237-257. DOI https://doi.org/10.3354/meps12754

  49. Essink, K., 1999. Ecological effects of dumping of dredged sediments; options for management. Journal of Coastal Conservation, 5, 69-80.

  50. Fahy, E., Carroll, J. & O'Toole, M., 2003. A preliminary account of fisheries for the surf clam Spisula solida (L) (Mactracea) in Ireland [On-line] http://www.marine.ie, 2004-03-16

  51. Fiege, D., Licher, F. & Mackie, A.S.Y., 2000. A partial review of the European Magelonidae (Annelida : Polychaeta) Magelona mirabilis redefined and M. johnstoni sp. nov. distinguished. Journal of the Marine Biological Association of the United Kingdom, 80, 215-234.

  52. Fish, J.D. & Fish, S., 1996. A student's guide to the seashore. Cambridge: Cambridge University Press.

  53. Folk, R.L., 1954. The distinction between grain size and mineral composition in sedimentary-rock nomenclature. 62The Journal of Geology, 344-359.

  54. Freese, L., Auster, P.J., Heifetz, J. & Wing, B.L., 1999. Effects of trawling on seafloor habitat and associated invertebrate taxa in the Gulf of Alaska. Marine Ecology Progress Series, 182, 119-126.

  55. Fretter, V. & Graham, A., 1981. The Prosobranch Molluscs of Britain and Denmark. Part 6. Molluscs of Britain and Denmark. Part 6. Journal of Molluscan Studies, Supplement 9, 309-313.

  56. Frölicher, T.L., Fischer, E.M. & Gruber, N., 2018. Marine heatwaves under global warming. Nature, 560 (7718), 360-364. DOI https://doi.org/10.1038/s41586-018-0383-9

  57. Garrard, S.L., Gambi, M.C., Scipione, M.B., Patti, F.P., Lorenti, M., Zupo, V., Paterson, D.M. & Buia, M.C., 2014. Indirect effects may buffer negative responses of seagrass invertebrate communities to ocean acidification. Journal of Experimental Marine Biology and Ecology, 461, 31-38. DOI https://doi.org/10.1016/j.jembe.2014.07.011

  58. Gaspar, M.B. & Monteiro, C.C., 1999. Gametogenesis and spawning in the subtidal white clam Spisula solida, in relation to temperature. Journal of the Marine Biological Association of the United Kingdom, 79, 753-755.

  59. Gaspar, M.B., Pereira, A.M., Vasconcelos, P. & Monteiro, C.C., 2004. Age and growth of Chamelea gallina from the Algarve coast (southern Portugal): influence of seawater temperature and gametogenic cycle on growth rate. Journal of Molluscan Studies, 70 (4), 371-377.

  60. Gaudin, François, Desroy, Nicolas, Dubois, Stanislas F, Broudin, Caroline, Cabioch, Louis, Fournier, Jérôme, Gentil, Franck, Grall, Jacques, Houbin, Céline, Le Mao, Patrick & Thiébaut, Éric, 2018. Marine sublittoral benthos fails to track temperature in response to climate change in a biogeographical transition zone. ICES Journal of Marine Science, 75 (6), 1894-1907. DOI https://doi.org/10.1093/icesjms/fsy095

  61. Gentil, F., Dauvin, J.C. & Menard, F., 1990. Reproductive biology of the polychaete Owenia fusiformis Delle Chiaje in the Bay of Seine (eastern English Channel). Journal of Experimental Marine Biology and Ecology, 142, 13-23.

  62. Ghiold, J 1982. Observations on the clypeasteroid Echinocyamus pusillus (O. F. Müller). Journal of Experimental Marine Biology and Ecology, 61(1), 57-74 DOI: https://doi.org/10.1016/0022-0981(82)90021-1

  63. Gilkinson, K., Paulin, M., Hurley, S. & Schwinghamer, P., 1998. Impacts of trawl door scouring on infaunal bivalves: results of a physical trawl door model/dense sand interaction. Journal of Experimental Marine Biology and Ecology, 224 (2), 291-312.

  64. Gilkinson, K.D., Gordon, D.C., MacIsaac, K.G., McKeown, D.L., Kenchington, E.L., Bourbonnais, C. & Vass, W.P., 2005. Immediate impacts and recovery trajectories of macrofaunal communities following hydraulic clam dredging on Banquereau, eastern Canada. ICES Journal of Marine Science: Journal du Conseil, 62 (5), 925-947.

  65. Grant, J. & Thorpe, B., 1991. Effects of suspended sediment on growth, respiration, and excretion of the soft shelled clam (Mya arenaria). Canadian Journal of Fisheries and Aquatic Sciences, 48, 1285-1292.

  66. Guillou, J. & Sauriau, F.G., 1985. Some observations on the biology and ecology of a Venus striatula population in the Bay of Douarnenez, Brittany. Journal of the Marine Biological Association of the United Kingdom, 65, 889-900.

  67. Hauton, C., Hall-Spencer, J.M. & Moore, P.G., 2003. An experimental study of the ecological impacts of hydraulic bivalve dredging on maerl. ICES Journal of Marine Science, 60, 381-392.

  68. Hayward, P., Nelson-Smith, T. & Shields, C. 1996. Collins pocket guide. Sea shore of Britain and northern Europe. London: HarperCollins.

  69. Hiscock, K., 1983. Water movement. In Sublittoral ecology. The ecology of shallow sublittoral benthos (ed. R. Earll & D.G. Erwin), pp. 58-96. Oxford: Clarendon Press.

  70. Hiscock, K., Langmead, O. & Warwick, R., 2004. Identification of seabed indicator species from time-series and other studies to support implementation of the EU Habitats and Water Framework Directives. Report to the Joint Nature Conservation Committee and the Environment Agency from the Marine Biological Association. Marine Biological Association of the UK, Plymouth. JNCC Contract F90-01-705. 109 pp.

  71. Hiscock, K., Sewell, J. & Oakley, J., 2005. Marine Health Check 2005. A report to guage the health of the UK’s sea-life. Godalming, WWF-UK.

  72. Hjulström, F., 1939. Transportation of detritus by moving water: Part 1. Transportation. Recent Marine Sediments, a Symposium (ed. P.D. Trask), pp. 5-31. Dover Publications, Inc.

  73. Hunt, J.D., 1925. The food of the bottom fauna of the Plymouth fishing grounds. Journal of the Marine Biological Association of the United Kingdom, 13, 560-599.

  74. Huthnance, J., 2010. Temperature and salinity, in: Charting the Progress 2: Ocean processes feeder report, section 3.2. (eds. Buckley, P., et al.): UKMMAS, Defra, London.

  75. IPCC (Intergovernmental Panel on Climate Change), 2019. IPCC Special Report on the Ocean and Cryosphere in a Changing Climate. Intergovernmental Panel on Climate Change, Geneva, Switzerland, 1170 pp. Available from https://www.ipcc.ch/srocc/home/

  76. Jacobson, M.Z., 2005. Studying ocean acidification with conservative, stable numerical schemes for nonequilibrium air-ocean exchange and ocean equilibrium chemistry. Journal of Geophysical Research: Atmospheres, 110 (D7). DOI https://doi.org/10.1029/2004JD005220

  77. JNCC (Joint Nature Conservation Committee), 2022.  The Marine Habitat Classification for Britain and Ireland Version 22.04. [Date accessed]. Available from: https://mhc.jncc.gov.uk/

  78. JNCC (Joint Nature Conservation Committee), 2022.  The Marine Habitat Classification for Britain and Ireland Version 22.04. [Date accessed]. Available from: https://mhc.jncc.gov.uk/

  79. JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line] http://www.jncc.gov.uk/mermaid

  80. Joaquim, S., Gaspar, M.B., Matias, D., Ben-Hamadou, R. & Arnold, W.S., 2008. Rebuilding viable spawner patches of the overfished Spisula solida (Mollusca: Bivalvia): a preliminary contribution to fishery sustainability. ICES Journal of Marine Science: Journal du Conseil, 65 (1), 60-64.

  81. Jones, M.L., 1968. On the morphology, feeding and behaviour of Magelona sp. Biological Bulletin of the Marine Laboratory, Woods Hole, 134, 272-297.

  82. Jones, N.S., 1950. Marine bottom communities. Biological Reviews, 25, 283-313.

  83. Künitzer, A., Basford, D., Craeymeersch, J.A., Dewarumez, J.M., Derjes, J., Duinevald, G.C.A., Eleftheriou, A., Heip, C, Herman, P., Kingston, P., Neirmann, U., Rachor, E., Rumohr, H. & Wilde, P.A.J. de, 1992. The benthic infauna of the North Sea: species distribution and assemblages. ICES Journal of Marine Science, 49, 127-143.

  84. Kaiser, M.J. & Spencer, B.E., 1995. Survival of by-catch from a beam trawl. Marine Ecology Progress Series, 126, 31-38.

  85. Kaiser, M.J., & Spencer, B.E., 1994a. A preliminary assessment of the immediate effects of beam trawling on a benthic community in the Irish Sea. In Environmental impact of bottom gears on benthic fauna in relation to natural resources management and protection of the North Sea. (ed. S.J. de Groot & H.J. Lindeboom). NIOZ-Rapport, 11, 87-94.

  86. Kaschl, A. & Carballeira, A., 1999. Behavioural responses of Venerupis decussata (Linnaeus, 1758) and Venerupis pullastra (Montagu, 1803) to copper spiked marine sediments. Boletin. Instituto Espanol de Oceanografia, 15, 383-394.

  87. Kenchington, E.L.R., Prena, J., Gilkinson, K.D., Gordon, D.C., Macisaac, K., Bourbonnais, C.; Schwinghamer, P.J., Rowell, T.W., McKeown, D.L. & Vass, W.P., 2001. Effects of experimental otter trawling on the macrofauna of a sandy bottom ecosystem on the Grand Banks of Newfoundland. Canadian Journal of Fisheries and Aquatic Sciences, 58, 1043-1057.

  88. Kenny, A.J. & Rees, H.L., 1996. The effects of marine gravel extraction on the macrobenthos: results 2 years post-dredging. Marine Pollution Bulletin, 32 (8-9), 615-622.

  89. Kingston, P.F., Dixon, I.M.T., Hamilton, S. & Moore, D.C., 1995. The impact of the Braer oil spill on the macrobenthic infauna of the sediments off the Shetland Islands. Marine Pollution Bulletin, 30 (7), 445-459.

  90. Kinne, O. (ed.), 1983. Diseases of marine animals, volume II. Introduction, Bivalvia to Scaphopoda. Biologische Anstalt Helgoland.

  91. Kinne, O. (ed.), 1984. Marine Ecology: A Comprehensive, Integrated Treatise on Life in Oceans and Coastal Waters.Vol. V. Ocean Management Part 3: Pollution and Protection of the Seas - Radioactive Materials, Heavy Metals and Oil. Chichester: John Wiley & Sons.

  92. Kirby, R.R., Beaugrand, G. & Lindley, J.A., 2008. Climate-induced effects on the meroplankton and the benthic-pelagic ecology of the North Sea. Limnology and Oceanography, 53 (5), 1805.

  93. Klawe, W.L. & Dickie, L.M., 1957. Biology of the bloodworm, Glycera dibranchiata Ehlers, and its relation to the bloodworm fishery of the Maritime Provinces. Bulletin of Fisheries Research Board of Canada, 115, 1-37.

  94. Kröncke, I., Dippner, J., Heyen, H. & Zeiss, B., 1998. Long-term changes in macrofaunal communities off Norderney (East Frisia, Germany) in relation to climate variability. Marine Ecology Progress Series, 167, 25-36.

  95. Kröncke, I., Reiss, H., Eggleton, J.D., Aldridge, J., Bergman, M.J. N., Cochrane, S., Craeymeersch, J.A., Degraer, S., Desroy, N., Dewarumez, J., Duineveld, G.C. A., Essink, K., Hillewaert, H., Lavaleye, M.S.S., Moll, A., Nehring, S., Newell, R., Oug, E., Pohlmann, T., Rachor, E., Robertson, M., Rumohr, H., Schratzberger, M., Smith, R., Berghe, E.V., Van Dalfsen, J., Van Hoey, G., Vincx, M., Willems, W. & Rees, H.L., 2011. Changes in North Sea macrofauna communities and species distribution between 1986 and 2000. Estuarine, Coastal and Shelf Science, 94 (1), 1-15.

  96. Lawrence, J.M., 1996. Mass mortality of echinoderms from abiotic factors. In Echinoderm Studies Vol. 5 (ed. M. Jangoux & J.M. Lawrence), pp. 103-137. Rotterdam: A.A. Balkema.

  97. Le Bot, S., Lafite, R., Fournier, M., Baltzer, A. & Desprez, M., 2010. Morphological and sedimentary impacts and recovery on a mixed sandy to pebbly seabed exposed to marine aggregate extraction (Eastern English Channel, France). Estuarine, Coastal and Shelf Science89221-233.

  98. Levell, D., Rostron, D. & Dixon, I.M.T., 1989. Sediment macrobenthic communities from oil ports to offshore oilfields. In Ecological Impacts of the Oil Industry, Ed. B. Dicks. Chicester: John Wiley & Sons Ltd.

  99. Li, Y., Zhang, H., Tang, C., Zou, T. & Jiang, D., 2016. Influence of Rising Sea Level on Tidal Dynamics in the Bohai Sea. 74 (SI), 22-31. DOI https://doi.org/10.2112/si74-003.1

  100. Long, D., 2006. BGS detailed explanation of seabed sediment modified Folk classification. Available from: http://www.emodnet-seabedhabitats.eu/PDF/GMHM3_Detailed_explanation_of_seabed_sediment_classification.pdf

  101. Lopez-Flores I., De la Herran, R., Garrido-Ramos, M.A., Navas, J.I., Ruiz-Rejon, C. & Ruiz-Rejon, M., 2004. The molecular diagnosis of Marteilia refringens and differentiation between Marteilia strains infecting oysters and mussels based on the rDNA IGS sequence. Parasitology19 (4), 411-419.

  102. Lopez-Jamar, E., Francesch, O., Dorrio, A.V. & Parra, S., 1995. Long term variation of the infaunal benthos of La Coruna Bay (NW Spain): results from a 12-year study (1982-1993). Scientia Marina, 59(suppl. 1), 49-61.

  103. Lowe, J., Bernie, D., Bett, P., Bricheno, L., Brown, S., Calvert, D., Clark, R.T., Eagle, K.E., Edwards, T., Fosser, G., Fung, F., Gohar, L., Good, P., Gregory, J., Harris, G.R., Howard, T., Kaye, N., Kendon, E.J., Krijnen, J., Maisey, P., McDonald, R.E., McInnes, R.N., McSweeney, C.F., Mitchell, J.F.B., Murphy, J.M., Palmer, M., Roberts, C., Rostron, J.W., Sexton, D.M.H., Thornton, H.E., Tinker, J., Tucker, S., Yamazaki, K. & Belcher, S., 2018. UKCP18 Science Overview Report. Meterological Office, Hadley Centre, Exeter, UK, 73 pp. Available from https://www.metoffice.gov.uk/research/approach/collaboration/ukcp/index

  104. Mackie, A.S.Y., James, J.W.C., Rees, E.I.S., Darbyshire, T., Philpott, S.L., Mortimer, K., Jenkins, G.O. & Morando, A., 2006. BIOMÔR 4. The Outer Bristol Channel Marine Habitat Study. Studies in marine biodiversity and systematics from the National Museum of Wales, Cardiff. BIOMÔR Reports 4: 1–249 and A1–A227, + DVD-ROM (2007).

  105. Mackie, A.S.Y., Oliver, P.G. & Rees, E.I.S., 1995. Benthic biodiversity in the southern Irish Sea. Studies in Marine Biodiversity and Systematics from the National Museum of Wales. BIOMOR Reports, no. 1.

  106. Masanja, F., Yang, K., Xu, Y., He, G. X., Liu, X. L., Xu, X., Jiang, X. Y., Xin, L., Mkuye, R., Deng, Y. W. & Zhao, L. Q., 2023. Impacts of marine heat extremes on bivalves. Frontiers in Marine Science, 10. DOI https://doi.org/10.3389/fmars.2023.1159261

  107. Maurer, D., Keck, R.T., Tinsman, J.C., Leatham, W.A., Wethe, C., Lord, C. & Church, T.M., 1986. Vertical migration and mortality of marine benthos in dredged material: a synthesis. Internationale Revue der Gesamten Hydrobiologie, 71, 49-63. DOI https://doi.org/10.1002/iroh.19860710106

  108. McDermott, J.J., 1984. The feeding biology of Nipponnemertes pulcher (Johnston) (Hoplonemertea), with some ecological implications. Ophelia, 23, 1-21.

  109. Meador, J.P., Varanasi, U. & Krone, C.A., 1993. Differential sensitivity of marine infaunal amphipods to tributyltin. Marine Biology, 116, 231-239.

  110. Marine Ecological Surveys Limited (MES), 2008. Marine Macrofauna Genus Trait Handbook. Marine Ecological Surveys Limited: Bath. 

  111. MES, 2010. Marine Macrofauna Genus Trait Handbook. Marine Ecological Surveys Limited. http://www.genustraithandbook.org.uk/

  112. Mills, E.L., 1967. The biology of an ampeliscid amphipod crustacean sibling species pair. Journal of the Fisheries Research Board of Canada, 24, 305-355.

  113. Moraitis, M. L., Valavanis, V. D. & Karakassis, I., 2019. Modelling the effects of climate change on the distribution of benthic indicator species in the Eastern Mediterranean Sea. Science of the Total Environment, 667, 16-24. DOI https://doi.org/10.1016/j.scitotenv.2019.02.338

  114. Morton, B., 2009. Aspects of the biology and functional morphology of Timoclea ovata (Bivalvia: Veneroidea: Venerinae) in the Azores, Portugal, and a comparison with Chione elevata (Chioninae). Açoreana, 6, 105-119.

  115. Mossman, H.L., Grant, A., Lawrence, P.J. & Davy, A.J., 2015. Biodiversity climate change impacts report card technical paper 10. Implications of climate change for coastal and inter-tidal habitats of the UK. Biodiversity climate change impacts, Living With Environmental Change, NERC, UKRI,  26 pp. Available from https://nerc.ukri.org/research/partnerships/ride/lwec/report-cards/biodiversity-source10/

  116. Moulaert, I. & Hostens, K., 2007. Post-extraction evolution of a macrobenthic community on the intensively extracted Kwintebank site in the Belgian part of the North Sea. CM Documents-ICES, (A:12).

  117. Navarro, J.M. & Widdows, J., 1997. Feeding physiology of Cerastoderma edule in response to a wide range of seston concentrations. Marine Ecology Progress Series, 152, 175-186.

  118. Niermann, U., 1996. Fluctuation and mass occurrence of Phoronis muelleri (Phoronidea) in the south-eastern North Sea during 1983-1988. Senckenbergiana Maritima, 28, 65-79.

  119. Niermann, U., Bauerfeind, E., Hickel, W. & Westernhagen, H.V., 1990. The recovery of benthos following the impact of low oxygen content in the German Bight. Netherlands Journal of Sea Research, 25 (1), 215-226. DOI https://doi.org/10.1016/0077-7579(90)90023-A

  120. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2024-03-29

  121. Olafsson, E.B. & Persson, L.E., 1986. The interaction between Nereis diversicolor (Muller) and Corophium volutator (Pallas) as a structuring force in a shallow brackish sediment. Journal of Experimental Marine Biology and Ecology, 103, 103-117.

  122. Olafsson, E.B., Peterson, C.H. & Ambrose, W.G. Jr., 1994. Does recruitment limitation structure populations and communities of macro-invertebrates in marine soft sediments: the relative significance of pre- and post-settlement processes. Oceanography and Marine Biology: an Annual Review, 32, 65-109

  123. Oliver, P.G., Holmes, A.M., Killeen, I.J. & Turner, J.A., 2016. Marine Bivalve Shells of the British Isles. Amgueddfa Cymru - National Museum Wales. Available from: http://naturalhistory.museumwales.ac.uk/britishbivalves [Cited:  3 July 2018].

  124. Palmer, M., Howard, T., Tinker, J., Lowe, J., Bricheno, L., Calvert, D., Edwards, T., Gregory, J., Harris, G., Krijnen, J., Pickering, M., Roberts, C. & Wolf, J., 2018. UKCP18 Marine Report. Met Office, The Hadley Centre, Exeter, UK, 133 pp. Available from https://www.metoffice.gov.uk/pub/data/weather/uk/ukcp18/science-reports/UKCP18-Marine-report.pdf

  125. Parapar, Julio, Martínez, Alejandro & Moreira, Juan, 2021. On the Systematics and Biodiversity of the Opheliidae and Scalibregmatidae. Diversity, 13 (2), 87. DOI: https://doi.org/10.3390/d13020087

  126. Pearson, T.H. & Rosenberg, R., 1978. Macrobenthic succession in relation to organic enrichment and pollution of the marine environment. Oceanography and Marine Biology: an Annual Review, 16, 229-311.

  127. Petersen, C.G.J., 1918. The sea bottom and its production of fish food. A survey of the work done in connection with valuation of the Denmark waters from 1883-1917. Report of the Danish Biological Station, 25, 1-62.

  128. Pickering, M.D., Wells, N.C., Horsburgh, K.J. & Green, J.A.M., 2012. The impact of future sea-level rise on the European Shelf tides. Continental Shelf Research, 35, 1-15. DOI https://doi.org/10.1016/j.csr.2011.11.011

  129. Picton, B.E. & Costello, M.J., 1998. BioMar biotope viewer: a guide to marine habitats, fauna and flora of Britain and Ireland. [CD-ROM] Environmental Sciences Unit, Trinity College, Dublin.

  130. Poggiale, J.C. & Dauvin, J.C., 2001. Long term dynamics of three benthic Ampelisca (Crustacea - Amphipoda) populations from the Bay of Morlaix (western English Channel) related to their disappearance after the Amoco Cadiz oil spill. Marine Ecology Progress Series, 214, 201-209.

  131. Powilleit, M., Graf, G., Kleine, J., Riethmuller, R., Stockmann, K., Wetzel, M.A. & Koop, J.H.E., 2009. Experiments on the survival of six brackish macro-invertebrates from the Baltic Sea after dredged spoil coverage and its implications for the field. Journal of Marine Systems, 75 (3-4), 441-451.

  132. Price, H., 1982. An analysis of factors determining seasonal variation in the byssal attachment strength of Mytilus edulis. Journal of the Marine Biological Association of the United Kingdom, 62 (01), 147-155

  133. Rabalais, N.N., Harper, D.E. & Turner, R.E., 2001. Responses of nekton and demersal and benthic fauna to decreasing oxygen concentrations. In: Coastal Hypoxia Consequences for Living Resources and Ecosystems, (Edited by: Rabalais, N. N. and Turner, R. E.), Coastal and Estuarine Studies 58, American Geophysical Union, pp. 115–128. Washington D.C.

  134. Rhoads, D.C. & Young, D.K., 1970. The influence of deposit-feeding organisms on sediment stability and community trophic structure. Journal of Marine Research, 28, 150-178.

  135. Richter, Detlev K & Bruckschen, Peter, 1998. Geochemistry of recent tests of Echinocyamus pusillus: constraints for temperature and salinity. Carbonates and Evaporites, 13, 157-167.

  136. Riedel, B., Zuschin, M. & Stachowitsch, M., 2012. Tolerance of benthic macrofauna to hypoxia and anoxia in shallow coastal seas: a realistic scenario. Marine Ecology Progress Series, 458, 39-52.

  137. Riera, R., Tuya, F., Ramos, E., Rodríguez, M. & Monterroso, Ó., 2012. Variability of macrofaunal assemblages on the surroundings of a brine disposal. Desalination, 291, 94-100.

  138. Robinson, R.F. & Richardson, C.A., 1998. The direct and indirect effects of suction dredging on a razor clam (Ensis arcuatus) population. ICES Journal of Marine Science, 55, 970-977.

  139. Rombouts, I., Beaugrand, G. & Dauvin, J. C., 2012. Potential changes in benthic macrofaunal distributions from the English Channel simulated under climate change scenarios. Estuarine Coastal and Shelf Science, 99, 153-161. DOI https://doi.org/10.1016/j.ecss.2011.12.026

  140. Salzwedel, H., 1979. Reproduction, growth, mortality and variations in abundance and biomass of Tellina fabula (Bivalvia) in the German Bight in 1975/1976. Veroffentlichungen des Instituts fur Meeresforschung in Bremerhaven, 18, 111-202.

  141. Salzwedel, H., Rachor, E. & Gerdes, D., 1985. Benthic macrofauna communities in the German Bight. Verifflithungen des Institut fur Meeresforschung in Bremerhaven, 20, 199-267.

  142. Sardá, R., Pinedo, S. & Martin, D., 1999. Seasonal dynamics of macroinfaunal key species inhabiting shallow soft-bottoms in the Bay of Blanes (NW Mediterranean). Publications Elsevier: Paris.

  143. Sardá, R., Pinedo, S., Gremare, A. & Taboada, S., 2000. Changes in the dynamics of shallow sandy-bottom assemblages due to sand extraction in the Catalan Western Mediterranean Sea. ICES Journal of Marine Science, 57 (5), 1446-1453.

  144. Schäfer, W., 1972. Ecology and palaeoecology of marine environments, 568 pp. Edinburgh: Oliver & Boyd.

  145. Sinderman, C.J., 1990. Principle diseases of marine fish and shellfish, 2nd edition, Volume 2. Diseases of marine shellfish. Academic Press, 521 pp.

  146. Smith, J.E. (ed.), 1968. 'Torrey Canyon'. Pollution and marine life. Cambridge: Cambridge University Press.

  147. Snelgrove, P.V., Grassle, J.P., Grassle, J.F., Petrecca, R.F. & Ma, H., 1999. In situ habitat selection by settling larvae of marine soft‐sediment invertebrates. Limnology and Oceanography, 44 (5), 1341-1347.

  148. Soemodinoto, A., Oey, B.L. & Ibkar-Kramadibrata, H., 1995. Effect of salinity decline on macrozoobenthos community of Cibeurum River estuary, Java, Indonesia. Indian Journal of Marine Sciences, 24, 62-67.

  149. Stamouli, M. & Papadopoulou, C., 1990. Trivalent Cr-51 bioaccumulation study in two mollusc species. Thalassographica. Athens, 13 suppl. 1, 49-52.

  150. Stenton-Dozey, J.M.E. & Brown, A.C., 1994. Short term changes in the energy balance of Venerupis corrugatus (Bivalvia) in relation to tidal availability of natural suspended particles. Marine Ecology Progress Series, 103, 57-64.

  151. Stickle, W.B. & Diehl, W.J., 1987. Effects of salinity on echinoderms. In Echinoderm Studies, Vol. 2 (ed. M. Jangoux & J.M. Lawrence), pp. 235-285. A.A. Balkema: Rotterdam.

  152. Stirling, E.A., 1975. Some effects of pollutants on the behaviour of the bivalve Tellina tenuis. Marine Pollution Bulletin, 6, 122-124.

  153. Stronkhorst, J., Hattum van, B. & Bowmer, T., 1999. Bioaccumulation and toxicity of tributyltin to a burrowing heart urchin and an amphipod in spiked, silty marine sediments. Environmental Toxicology and Chemistry, 18 (10), 2343-2351. DOI https://doi.org/10.1002/etc.5620181031

  154. Suchanek, T.H., 1993. Oil impacts on marine invertebrate populations and communities. American Zoologist, 33, 510-523. DOI https://doi.org/10.1093/icb/33.6.510

  155. Tait, R.V. & Dipper, R.A., 1998. Elements of Marine Ecology. Reed Elsevier.

  156. Tan, K. & Zheng, H. P., 2020. Ocean acidification and adaptive bivalve farming. Science of the Total Environment, 701. DOI https://doi.org/10.1016/j.scitotenv.2019.134794

  157. Thomas, R., 1975. Functional morphology, ecology, and evolutionary conservatism in the Glycymerididae (Bivalvia). Palaeontology, 18 (2), 217-254.

  158. Thorson, G., 1957. Bottom communities (sublittoral or shallow shelf). Memoirs of the Geological Society of America, 67, 461-534.

  159. Thouzeau, G., Jean, F. & Del Amo, Y., 1996. Sedimenting phytoplankton as a major food source for suspension-feeding queen scallops (Aequipecten opercularis L.) off Roscoff (western English Channel) ? Journal of Shellfish Research, 15, 504-505.

  160. Thrush, S.F., 1986. Community structure on the floor of a sea-lough: are large epibenthic predators important? Journal of Experimental Marine Biology and Ecology, 104, 171-183.

  161. Tillin, H.M., Hiddink, J.G., Jennings, S. & Kaiser, M.J., 2006. Chronic bottom trawling alters the functional composition of benthic invertebrate communities on a sea-basin scale. Marine Ecology Progress Series, 318, 31-45.

  162. Tuck, I.D., Atkinson, R.J.A. & Chapman, C.J., 2000. Population biology of the Norway lobster Nephrops norvegicus (L.) in the Firth of Clyde, Scotland II: Fecundity and size at onset of sexual maturity. ICES Journal of Marine Science, 57, 1227-1239.

  163. Tyler, P.A., 1977b. Sublittoral community structure of Oxwich Bay, South Wales, in relation to sedimentological, physical oceanographical and biological parameters. In Biology of Benthic Organisms: 11th European Symposium on Marine Biology, Galway, October 1976 (ed. B.F. Keegan, P.O. Ceidigh and P.J.S. Boaden), 559-566. Pergamon Press, Oxford.

  164. UKTAG, 2014. UK Technical Advisory Group on the Water Framework Directive [online]. Available from: http://www.wfduk.org

  165. Valentine, P.C., Carman, M.R., Blackwood, D.S. & Heffron, E.J., 2007. Ecological observations on the colonial ascidian Didemnum sp. in a New England tide pool habitat. Journal of Experimental Marine Biology and Ecology, 342 (1), 109-121.

  166. Van Dalfsen, J.A., Essink, K., Toxvig Madsen, H., Birklund, J., Romero, J. & Manzanera, M., 2000. Differential response of macrozoobenthos to marine sand extraction in the North Sea and the Western Mediterranean. ICES Journal of Marine Science, 57 (5), 1439-1445.

  167. Vlaminck, Ellen, Cepeda, Esther, Moens, Tom & Van Colen, Carl, 2023. Ocean acidification modifies behaviour of shelf seabed macrofauna: A laboratory study on two ecosystem engineers, Abra alba and Lanice conchilega. Journal of Experimental Marine Biology and Ecology, 558, 151831. DOI https://doi.org/10.1016/j.jembe.2022.151831

  168. Vlaminck, Ellen, Moens, Tom, Vanaverbeke, Jan & Van Colen, Carl, 2022. Physiological response to seawater pH of the bivalve Abra alba, a benthic ecosystem engineer, is modulated by low pH. Marine Environmental Research, 179, 105704. DOI https://doi.org/10.1016/j.marenvres.2022.105704

  169. Warwick, R. M. & Pearce, B., 2020. Irregular recruitment of the echinoid Echinocyamus pusillus and its implications for biological traits analysis. Journal of the Marine Biological Association of the United Kingdom, 100 (7), 1123-1127. DOI https://doi.org/10.1017/s0025315420000934

  170. Warwick, R.M. & Davis, J.R., 1977. The distribution of sublittoral macrofauna communities in the Bristol Channel in relation to the substrate. Estuarine and Coastal Marine Science, 5, 267-288.

  171. Warwick, R.M. & Uncles, R.J., 1980. Distribution of benthic macrofauna associations in the Bristol Channel in relation to tidal stress. Marine Biology Progress Series, 3, 97-103.

  172. Warwick, R.M., George, C.L. & Davies, J.R., 1978. Annual macrofauna production in a Venus community. Estuarine and Coastal Marine Science, 7, 215-241.

  173. Wicks, L.C. & Roberts, J.M., 2012. Benthic invertebrates in a high-CO2 world. CRC Press.

  174. Widdows, J., Bayne, B.L., Livingstone, D.R., Newell, R.I.E. & Donkin, P., 1979. Physiological and biochemical responses of bivalve molluscs to exposure to air. Comparative Biochemistry and Physiology, 62A, 301-308.

  175. Wilson, J.G., 1978. Upper temperature tolerances of Tellina tenuis and T. fabula. Marine Biology, 45, 123-128.

Citation

This review can be cited as:

Tillin, H.M. & Watson, A., 2024. Echinocyamus pusillus, Ophelia borealis and Abra prismatica in circalittoral fine sand. In Tyler-Walters H. Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 29-03-2024]. Available from: https://marlin.ac.uk/habitat/detail/1131

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Last Updated: 07/02/2024