The Marine Life Information Network

Substratum loss

Benchmark. All of the substratum occupied by the species or biotope under consideration is removed. A single event is assumed for sensitivity assessment. Once the activity or event has stopped (or between regular events) suitable substratum remains or is deposited. Species or community recovery assumes that the substratum within the habitat preferences of the original species or community is present. Further details

Evidence

Spio filicornis lives in the sediment and a loss of substratum would cause a loss of population. Therefore, an intolerance of high has been recorded. Recoverability has been recorded as high (see additional information below).

Smothering

Benchmark. All of the population of a species or an area of a biotope is smothered by sediment to a depth of 5 cm above the substratum for one month. Impermeable materials, such as concrete, oil, or tar, are likely to have a greater effect. Further details.

Evidence

Spio filicornis lives in the sediment and uses sediment grains to make its tube. It is likely that Spio filicornis will be able to move up through any extra sediment, therefore intolerance, has been recorded as low. Recoverability will probably be very high (see additional information below). However, smothering by impermeable material is likely to result in anoxic conditions and have a greater impact.

Increase in suspended sediment

Benchmark. An arbitrary short-term, acute change in background suspended sediment concentration e.g., a change of 100 mg/l for one month. The resultant light attenuation effects are addressed under turbidity, and the effects of rapid settling out of suspended sediment are addressed under smothering. Further details

Evidence

Spio filicornis lives in the sediment and is unlikely to be perturbed by an increase in suspended sediment. There may be an increase in the amount of food avaliable therefore, tolerant* has been recorded.

Decrease in suspended sediment

Benchmark. An arbitrary short-term, acute change in background suspended sediment concentration e.g., a change of 100 mg/l for one month. The resultant light attenuation effects are addressed under turbidity, and the effects of rapid settling out of suspended sediment are addressed under smothering. Further details

Evidence

Spio filicornis is a surface deposit feeder and relies on a supply of nutrients at the sediment surface. A decrease in suspended sediment is likely to lead to a reduction in the amount of available food. A reduction in food availability may impair growth and reproduction but is unlikely to cause mortality. Intolerance has, therefore, been recorded as low. The benchmark states the decrease in siltation would only happen for a month, once the level of suspended sediment increases normal feeding could resume, recoverability has therefore been recorded as immediate.

Desiccation

1. A normally subtidal, demersal or pelagic species including intertidal migratory or under-boulder species is continuously exposed to air and sunshine for one hour.
2. A normally intertidal species or community is exposed to a change in desiccation equivalent to a change in position of one vertical biological zone on the shore, e.g., from upper eulittoral to the mid eulittoral or from sublittoral fringe to lower eulittoral for a period of one year. Further details.

Evidence

Spio filicornis lives infaunally so is protected from desiccation stress. Some individuals live in the intertidal so may be tolerant to some emersion of the substratum. Individuals living in coarser sands are more likely to be affected due to increased porosity of the sand and increased exposure to desiccation. Intolerance has, therefore, been recorded as intermediate. Recoverability has been recorded as very high (see additional information below).

Increase in emergence regime

Benchmark. A one hour change in the time covered or not covered by the sea for a period of one year. Further details

Evidence

Spio filicornis is found in the intertidal so may be tolerant to some emersion of the substratum. Spio filicornis lives infaunally so may be able to retract into its tube to reduce desiccation stress. Individuals in coarser sands are more likely to be affected. Intolerance has, therefore been recorded as intermediate. A recoverability of very high has been recorded (see additional information below).

Decrease in emergence regime

Benchmark. A one hour change in the time covered or not covered by the sea for a period of one year. Further details

Evidence

Spio filicornis thrives in the sublittoral zone and therefore could potentially benefit from a decrease in emergence. It is possible that decreased emergence would allow the species to colonize further up the shore. Hence tolerant* has been recorded.

Increase in water flow rate

A change of two categories in water flow rate (view glossary) for 1 year, for example, from moderately strong (1-3 knots) to very weak (negligible). Further details

Evidence

A change in water flow rate will change sediment characteristics. Increased water flow will increase deposits of coarser sediments. Changes in water flow are likely to change the distribution and extent of the population due to changes in the preferred substratum of Spio filicornis. Therefore, intolerance has been recorded as intermediate. A recoverability of very high has been recorded (see additional information below).

Decrease in water flow rate

A change of two categories in water flow rate (view glossary) for 1 year, for example, from moderately strong (1-3 knots) to very weak (negligible). Further details

Evidence

A change in water flow rate will change sediment characteristics. A decrease in water flow rate will lead to deposits of finer sediments. The distribution and extent of the population is likely to alter due to changes in the preferred substratum of Spio filicornis. Therefore, an intolerance of intermediate has been recorded. A recoverability of ver high has been recorded (see additional information below).

Increase in temperature

1. A short-term, acute change in temperature; e.g., a 5°C change in the temperature range for three consecutive days. This definition includes ‘short-term’ thermal discharges.
2. A long-term, chronic change in temperature; e.g. a 2°C change in the temperature range for a year. This definition includes ‘long term’ thermal discharges.

For intertidal species or communities, the range of temperatures includes the air temperature regime for that species or community. Further details

Evidence

No information was found regarding the intolerance of Spio filicornis to temperature. However, inferences can be made from its geographical distribution. Spio filicornis is found in the Mediterranean (Hayward & Ryland, 1995) and therfore surviving higher seawater temperatures than in Britain and Ireland. Chronic temperature change is likely to have little, or no effect. An acute change in temperature may cause physiological stress but is unlikely to lead to mortality. Intolerance has, therefore, been recorded as low. A recoverability of very high has been recorded (see additional information below).

Decrease in temperature

1. A short-term, acute change in temperature; e.g., a 5°C change in the temperature range for three consecutive days. This definition includes ‘short-term’ thermal discharges.
2. A long-term, chronic change in temperature; e.g. a 2°C change in the temperature range for a year. This definition includes ‘long term’ thermal discharges.

For intertidal species or communities, the range of temperatures includes the air temperature regime for that species or community. Further details

Evidence

No information was found regarding the intolerance of Spio filicornis to temperature. However, inferences can be made from its geographical distribution. Spio filicornis is found in the Arctic and Baltic (Hayward & Ryland, 1995) and therefore surviving colder temperatures than occur in Britain and Ireland. these water. Chronic temperature change is likely to have little, or no effect. An acute change in temperature may result in physiological stress but is unlikely to lead to mortality. Intolerance has, therefore, been recorded as low. A recoverability of very high has been recorded (see additional information below).

Increase in turbidity

1. A short-term, acute change; e.g., two categories of the water clarity scale (see glossary) for one month, such as from medium to extreme turbidity.
2. A long-term, chronic change; e.g., one category of the water clarity scale (see glossary) for one year, such as from low to medium turbidity. Further details

Evidence

Spio filicornis is found in estuarine regions which experience high levels of turbidity. An increase in turbidity will lead to reduced light penetration of the water column. Spio filicornis is not affected by light availability, therefore, tolerant has been recorded.

Decrease in turbidity

1. A short-term, acute change; e.g., two categories of the water clarity scale (see glossary) for one month, such as from medium to extreme turbidity.
2. A long-term, chronic change; e.g., one category of the water clarity scale (see glossary) for one year, such as from low to medium turbidity. Further details

Evidence

Spio filicornis is not affected by light availability, therefore, tolerant has been recorded.

Increase in wave exposure

A change of two ranks on the wave exposure scale (view glossary) e.g., from Exposed to Extremely exposed for a period of one year. Further details

Evidence

Tamaki (1987) reported that adult Spio filicornis could burrow 5-10 cm into the sediment and so are unlikely to be affected by an increase in wave exposure. Juvenile Spio filicornis could only burrow into the top 2 cm of the sediment and so may be affected by wave action. A change from sheltered to moderately exposed is likely to remove all but coarse sand, reducing the amount of preferred substratum for Spio filicornis. Intolerance has therefore been recorded as high. A recoverability of very high has been recorded (see additional information below).

Decrease in wave exposure

A change of two ranks on the wave exposure scale (view glossary) e.g., from Exposed to Extremely exposed for a period of one year. Further details

Evidence

Spio filicornis occurs from sheltered to ultra sheltered habitats and a decrease in wave exposure is unlikely to have adverse effects. Therefore, tolerant has been recorded.

Noise

1. Underwater noise levels e.g., the regular passing of a 30-metre trawler at 100 metres or a working cutter-suction transfer dredge at 100 metres for one month during important feeding or breeding periods.
2. Atmospheric noise levels e.g., the regular passing of a Boeing 737 passenger jet 300 metres overhead for one month during important feeding or breeding periods. Further details

Evidence

No information was found concerning intolerance of Spio filicornis to noise. However, it is unlikely to be affected by noise and vibrations at the level of the benchmark.

Visual presence

Benchmark. The continuous presence for one month of moving objects not naturally found in the marine environment (e.g., boats, machinery, and humans) within the visual envelope of the species or community under consideration. Further details

Evidence

Spio filicornis inhabits a tube and its visual range is probably very limited. Not sensitive has, therefore, been recorded.

Abrasion & physical disturbance

Benchmark. Force equivalent to a standard scallop dredge landing on or being dragged across the organism. A single event is assumed for assessment. This factor includes mechanical interference, crushing, physical blows against, or rubbing and erosion of the organism or habitat of interest. Where trampling is relevant, the evidence and trampling intensity will be reported in the rationale. Further details.

Evidence

Spio filicornis is a soft bodied organism that exposes its palps at the surface while feeding. It lives infaunally in sandy sediment and any physical disturbance that penetrates the sediment, for example dredging or dragging an anchor, would lead to physical damage of Spio filicornis. However, adult worms can burrow up to 10 cm down and may escape the disturbance. Juveniles can only burrow up to 2 cm into the sediment and are likely to be affected. However, individuals are likely to pass through a passing scallop dredge due to their small size. Bergman & Hup (1992) reported that the total density of spionids actually increased with increased fishing disturbance., presumably due to their ability to colonize newly exposed substratum. Hall et al. (1990) investigated the impact of hydraulic dredging for razor clams. They reported that any effects only persist for a short time, with the community restored after approximately 40 days in stormy conditions. The population density of Spio filicornis was slightly reduced in the dredged site relative to the control site but its abundance had increased over that of the control site ater 40 days. However, the control site showed a similar level of variation in abundance. An intolerance of intermediate has therefore been recorded. Recoverability has been recorded as very high (see additional information below).

Displacement

Benchmark. Removal of the organism from the substratum and displacement from its original position onto a suitable substratum. A single event is assumed for assessment. Further details

Evidence

If Spio filicornis is displaced from the substratum it is likely that it could burrow back into the sediment and rebuild it tube. It would, however, be more susceptible to predation whilst exposed and there would be significant energy expenditure rebuilding the tube. Therefore, intolerance has been recorded as low. A recoverability of very high has been recorded (see additional information below).

Synthetic compound contamination

Sensitivity is assessed against the available evidence for the effects of contaminants on the species (or closely related species at low confidence) or community of interest. For example:

• evidence of mass mortality of a population of the species or community of interest (either short or long term) in response to a contaminant will be ranked as high sensitivity;
• evidence of reduced abundance, or extent of a population of the species or community of interest (either short or long term) in response to a contaminant will be ranked as intermediate sensitivity;
• evidence of sub-lethal effects or reduced reproductive potential of a population of the species or community of interest will be assessed as low sensitivity.

The evidence used is stated in the rationale. Where the assessment can be based on a known activity then this is stated. The tolerance to contaminants of species of interest will be included in the rationale when available; together with relevant supporting material. Further details.

Evidence

No information was found directly relating to the effects of synthetic chemicals on Spio filicornis. However, there is evidence from other polychaete species. Collier & Pinn (1998) investigated the effect on the benthos of Ivermectin, treatment for infestations of sea-lice on farmed salmonids. The ragworm Hediste diversicolor exhibited 100% mortality after 14 days when exposed to 8mg/m² of invermectin in a microcosm. The blow lug, Arenicola marina, was also intolerant of invermectin through 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 1-3µg/l there was no significant effect on the abundance of Hediste diversicolor or Cirratulus cirratus after 9 weeks in a microcosm. However, no juvenile polychaetes were retrieved from the substratum so TBT may have had an effect on the larval and/or juvenile stages of these polychaetes. The high mortality rate of polychaetes due to exposure to invermectin suggests a high intolerance to synthetic chemicals. An intolerance of high has been inferred, but with a very low confidence level. Recoverability has been recorded as high (see additional information below).

Heavy metal contamination

Evidence

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 that it is tolerant of heavy metal pollution. Intolerance has therefore been recorded as low. A recoverability of very high has been recorded (see additional information below).

Hydrocarbon contamination

Evidence

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. Intolerance has therefore been recorded as low. A recoverability of very high has been recorded (see additional information below).

Radionuclide contamination

Evidence

No evidence was found regarding the intolerance of Spio filicornis to radionuclide contamination.

Changes in nutrient levels

Evidence

Spio filicornis is often found in environments subject to high levels of nutrients, for example, it was found in areas of the Firth of Forth exposed to high levels of sewage pollution (Read et al.1983). Spio filicornis is also found in nutrient poor areas (Diaz-Castaneda, et al., 1989). Therefore, an intolerance of low has been recorded. A recoverability of very high has been recorded (see additional information below).

Increase in salinity

1. A short-term, acute change; e.g., a change of two categories from the MNCR salinity scale for one week (view glossary) such as from full to reduced.
2. A long-term, chronic change; e.g., a change of one category from the MNCR salinity scale for one year (view glossary) such as from reduced to low. Further details.

Evidence

Spio filicornis lives in fully saline conditions, an increase in salinity would be to hypersaline conditions. No information was found concerning the reaction of Spio filicornis to hypersaline conditions (>40 psu). It is unlikely that Spio filicornis would experience hypersaline conditions, therefore, not relevant has been recorded.

Decrease in salinity

1. A short-term, acute change; e.g., a change of two categories from the MNCR salinity scale for one week (view glossary) such as from full to reduced.
2. A long-term, chronic change; e.g., a change of one category from the MNCR salinity scale for one year (view glossary) such as from reduced to low. Further details.

Evidence

Spio filicornis is a euryhaline species (Gosner, 1971), inhabiting fully saline and estuarine habitats. However, populations in estuaries would be intolerant of further reductions in salinity. Intolerance has, therefore, been recorded low at the benchmark level.

Changes in oxygenation

Benchmark.  Exposure to a dissolved oxygen concentration of 2 mg/l for one week. Further details.

Evidence

No information was found on the tolerance of Spio filicornis to changes in oxygenation. Cole et al. (1999) suggest adverse effects on marine species at oxygen concentrations below 4 mg/l and probable adverse effects occur below 2 mg/l. Capitella capitata survived for 13 days at 0.8-0.9 ml/l and more than 24 days at oxygen levels of 1.5 ml/l. In hypoxic conditions it stopped burrowing and feeding so mortality is likely indirectly through starvation (Pearson & Rosenberg, 1978). Intolerance has, therefore, been recorded as intermediate. A recoverability of very high has been recorded (see additional information below).

Introduction of microbial pathogens/parasites

Benchmark. Sensitivity can only be assessed relative to a known, named disease, likely to cause partial loss of a species population or community. Further details.

Evidence

No information was found on diseases of Spio filicornis.

Introduction of non-native species

Sensitivity assessed against the likely effect of the introduction of alien or non-native species in Britain or Ireland. Further details.

Evidence

No information was found on non-native species that may compete with Spio filicornis.

Extraction of this species

Benchmark. Extraction removes 50% of the species or community from the area under consideration. Sensitivity will be assessed as 'intermediate'. The habitat remains intact or recovers rapidly. Any effects of the extraction process on the habitat itself are addressed under other factors, e.g. displacement, abrasion and physical disturbance, and substratum loss. Further details.

Evidence

No information was found that Spio filicornis is extracted deliberately therefore not relevant has been recorded.

Extraction of other species

Benchmark. A species that is a required host or prey for the species under consideration (and assuming that no alternative host exists) or a keystone species in a biotope is removed. Any effects of the extraction process on the habitat itself are addressed under other factors, e.g. displacement, abrasion and physical disturbance, and substratum loss. Further details.

Evidence

Hall et al. (1990) investigated the impact of hydraulic dredging for razor clams on an infaunal community. They found that any effects only persist for a short time, with the community restored after approximately 40 days. Bergman & Hup (1992) reported that the total density of spionids actually increased with increased fishing disturbance. Intolerance has therefore been recorded as low. A recoverability of very high has been recorded (see additional information below).