The Marine Life Information Network

Bottom water temperatures in areas off the continental shelf are expected to increase by a nominal 1°C under both the middle and high emission scenario. Munida is the most cosmopolitan and diverse genus of the Galatheids from the genus Munida spp. occupying a wide bathymetric range from shallow water down to more than 3,000 m depth (Wehrtmann et al., 2010). Each species appears to occupy overlapping, and yet distinct, depth ranges (Wehrtmann et al., 2010).  

Of the four species found in the NE Atlantic, three occur in the Mediterranean as well. Munida rugosa is known to inhabit shallow waters down to depths of 300 m in the NE Atlantic (Hartnoll et al., 1992) and Mediterranean (Ateş et al., 2005), whilst the species Munida intermedia is a small species which occurs at depths of 120 -800 m, from the UK to West Africa in the Eastern Atlantic, including the Mediterranean and the Adriatic Seas (Gramitto & Froglia, 1998). Munida sarsi is the most northern of the NE Atlantic species, being distributed from Norway to the Bay of Biscay, and is found at depths of 200 – 1000 m, although its most common depth distribution is between 250 – 450 m (Rice & de Saint Laurent, 1986). Munida tenuimana has the deepest depth distribution, occurring from 250 m, although rarely seen above 550 m depth, down to 1775 m, and is distributed from Iceland and Norway, down to the coast of Spain, Portugal, and into the Mediterranean (Rice & de Saint Laurent, 1986)

Experimental exposure to a sharp 10°C increase in water temperatures from 5 to 15°C led to increased oxygen consumption, and week-long exposure resulted in mortality in the deep water squat lobsters; Munida rugosa and Munida sarsi (Zainal et al., 1992). This suggests these species are sensitive to large changes in temperature, although this experimental increase is significantly higher than the temperature increase expected for the bathyal by the end of this century, and hence isn’t taken into consideration in the scoring.

Sensitivity Assessment. Three of the four NE Atlantic species of Munida sp. occur in the Mediterranean, suggesting that they will be able to withstand a 1°C temperature increase, and Munida intermedia (which is found at its northern limit in the UK) may actually benefit. Munida sarsi is a cold water species and may be the species most affected by a temperature rise, although it does have a more southerly distribution than the UK (occurring in the Bay of Biscay), and is likely to be able to withstand a small temperature increase of 1°C. If the abundance of this species did decrease in response to this temperature rise, it is likely that one of the other species would increase their abundance accordingly. As such, under all three scenarios (middle and high emission and extreme scenarios) resistance of this biotope has been assessed as ‘High’ and their resilience assessed as ‘High’ so that this biotope is considered ‘Not sensitive’ to ocean warming at the benchmark level. 

Bottom water temperatures in areas off the continental shelf are expected to increase by a nominal 1°C under both the middle and high emission scenario. Munida is the most cosmopolitan and diverse genus of the Galatheids from the genus Munida spp. occupying a wide bathymetric range from shallow water down to more than 3,000 m depth (Wehrtmann et al., 2010). Each species appears to occupy overlapping, and yet distinct, depth ranges (Wehrtmann et al., 2010).  

Of the four species found in the NE Atlantic, three occur in the Mediterranean as well. Munida rugosa is known to inhabit shallow waters down to depths of 300 m in the NE Atlantic (Hartnoll et al., 1992) and Mediterranean (Ateş et al., 2005), whilst the species Munida intermedia is a small species which occurs at depths of 120 -800 m, from the UK to West Africa in the Eastern Atlantic, including the Mediterranean and the Adriatic Seas (Gramitto & Froglia, 1998). Munida sarsi is the most northern of the NE Atlantic species, being distributed from Norway to the Bay of Biscay, and is found at depths of 200 – 1000 m, although its most common depth distribution is between 250 – 450 m (Rice & de Saint Laurent, 1986). Munida tenuimana has the deepest depth distribution, occurring from 250 m, although rarely seen above 550 m depth, down to 1775 m, and is distributed from Iceland and Norway, down to the coast of Spain, Portugal, and into the Mediterranean (Rice & de Saint Laurent, 1986)

Experimental exposure to a sharp 10°C increase in water temperatures from 5 to 15°C led to increased oxygen consumption, and week-long exposure resulted in mortality in the deep water squat lobsters; Munida rugosa and Munida sarsi (Zainal et al., 1992). This suggests these species are sensitive to large changes in temperature, although this experimental increase is significantly higher than the temperature increase expected for the bathyal by the end of this century, and hence isn’t taken into consideration in the scoring.

Sensitivity Assessment. Three of the four NE Atlantic species of Munida sp. occur in the Mediterranean, suggesting that they will be able to withstand a 1°C temperature increase, and Munida intermedia (which is found at its northern limit in the UK) may actually benefit. Munida sarsi is a cold water species and may be the species most affected by a temperature rise, although it does have a more southerly distribution than the UK (occurring in the Bay of Biscay), and is likely to be able to withstand a small temperature increase of 1°C. If the abundance of this species did decrease in response to this temperature rise, it is likely that one of the other species would increase their abundance accordingly. As such, under all three scenarios (middle and high emission and extreme scenarios) resistance of this biotope has been assessed as ‘High’ and their resilience assessed as ‘High’ so that this biotope is considered ‘Not sensitive’ to ocean warming at the benchmark level. 

Bottom water temperatures in areas off the continental shelf are expected to increase by a nominal 1°C under both the middle and high emission scenario. Munida is the most cosmopolitan and diverse genus of the Galatheids from the genus Munida spp. occupying a wide bathymetric range from shallow water down to more than 3,000 m depth (Wehrtmann et al., 2010). Each species appears to occupy overlapping, and yet distinct, depth ranges (Wehrtmann et al., 2010).  

Of the four species found in the NE Atlantic, three occur in the Mediterranean as well. Munida rugosa is known to inhabit shallow waters down to depths of 300 m in the NE Atlantic (Hartnoll et al., 1992) and Mediterranean (Ateş et al., 2005), whilst the species Munida intermedia is a small species which occurs at depths of 120 -800 m, from the UK to West Africa in the Eastern Atlantic, including the Mediterranean and the Adriatic Seas (Gramitto & Froglia, 1998). Munida sarsi is the most northern of the NE Atlantic species, being distributed from Norway to the Bay of Biscay, and is found at depths of 200 – 1000 m, although its most common depth distribution is between 250 – 450 m (Rice & de Saint Laurent, 1986). Munida tenuimana has the deepest depth distribution, occurring from 250 m, although rarely seen above 550 m depth, down to 1775 m, and is distributed from Iceland and Norway, down to the coast of Spain, Portugal, and into the Mediterranean (Rice & de Saint Laurent, 1986)

Experimental exposure to a sharp 10°C increase in water temperatures from 5 to 15°C led to increased oxygen consumption, and week-long exposure resulted in mortality in the deep water squat lobsters; Munida rugosa and Munida sarsi (Zainal et al., 1992). This suggests these species are sensitive to large changes in temperature, although this experimental increase is significantly higher than the temperature increase expected for the bathyal by the end of this century, and hence isn’t taken into consideration in the scoring.

Sensitivity Assessment. Three of the four NE Atlantic species of Munida sp. occur in the Mediterranean, suggesting that they will be able to withstand a 1°C temperature increase, and Munida intermedia (which is found at its northern limit in the UK) may actually benefit. Munida sarsi is a cold water species and may be the species most affected by a temperature rise, although it does have a more southerly distribution than the UK (occurring in the Bay of Biscay), and is likely to be able to withstand a small temperature increase of 1°C. If the abundance of this species did decrease in response to this temperature rise, it is likely that one of the other species would increase their abundance accordingly. As such, under all three scenarios (middle and high emission and extreme scenarios) resistance of this biotope has been assessed as ‘High’ and their resilience assessed as ‘High’ so that this biotope is considered ‘Not sensitive’ to ocean warming at the benchmark level. 

Marine heatwaves caused by increased air-sea flux of heat are only expected to penetrate surface waters (≤ 50 m) (Cerrano et al., 2000, Garrabou et al., 2009; Dan Smale, pers. comms.) Therefore, sensitivity to marine heatwaves is probably ‘Not relevant’ in this bathyal habitat.

Marine heatwaves caused by increased air-sea flux of heat are only expected to penetrate surface waters (≤ 50 m) (Cerrano et al., 2000, Garrabou et al., 2009; Dan Smale, pers. comms.) Therefore, sensitivity to marine heatwaves is probably ‘Not relevant’ in this bathyal habitat.

The absorption of carbon dioxide from the atmosphere and the resultant decrease in pH leads to changes in the carbonate chemistry of the oceans; an increase in hydrogen ions and a decrease in carbonate ions, which are needed for calcification. When the aragonite saturation state falls below 1, shells, coral skeleton, and other aragonitic structures start to dissolve.  This results in the shoaling of the aragonite saturation horizon (ASH). The ASH is defined as the depth in the oceans at which aragonite saturation equals 1. Below this depth, the aragonite saturation state (Ω_Ar) will fall below 1, and dissolution of calcified structures that are not protected by living tissue (e.g. coral reef and fragments) may occur. Currently, the depth of the ASH in the North Atlantic is approximately 2000m (Jiang et al., 2015) but this depth is already 80-150 m shallower than the past two centuries (Chung et al., 2003, Feely et al., 2004). By the end of this century, the ASH is expected to reach depths of up to 400 m under the high emission scenario (RCP 8.5) and 600 m for the middle emission scenario (RCP 4.5) (Zheng & Long, 2014).

Little is known of the effects of ocean acidification on squat lobsters, although at a submarine canyon off the coast of Australia, Munidopsis sp. has been found living at depths of 1357 m, >300 m below the ASH (Trotter et al., 2019). Whilst this is the only literature which describes the depth of a squat lobster in relation to the aragonite saturation state, the fact that species from the genus Munida are found at depths of more than 3000 m suggests that this genus is likely to be robust to future ocean acidification, even if the ASH does rise to the upper bathyal.

The abundance of squat lobsters is most likely intrinsically linked to the heterogeneity of the coral rubble and gravel in which this group of animals resides within this biotope. Squat lobsters often have a symbiotic lifestyle with their habitat and two species are commonly associated with Lophelia pertusa reef and rubble; Munida rugosa and Munidopsis serricornis (Baeza, 2011). Habitat complexity mediates predator-prey interactions through the provision of refuges (Rogers et al., 2014), and there is a strong positive relationship between complexity and species density and biomass (Graham & Nash, 2013). For Lophelia pertusa, both areas of live coral and areas of coral rubble enhance species density, compared to areas with no coral framework (Jonsson et al., 2004).

In an experiment, Voight (2010) looked at the dissolution of dead Lophelia pertusa rubble fragments in response to different aragonite saturation states. After 50 days, minimal dissolution was seen at Ω_Ar 1.02, but dissolution became more apparent at Ω_Ar 0.71 – 0.55 (Voigt, 2010). Furthermore, Hennige et al. (2015) observed dissolution of the exposed skeleton at aragonite saturation states < 1 and found that Lophelia pertusa coral framework became 20-30% weaker at low pH, even before saturation state fell below 1 (Ω_Ar 1.19-1.09). Extensive coral graveyards have been observed below the aragonite saturation horizon in Australia, which are thought to have flourished during the last ice age 18 – 33 thousand years ago (Trotter et al., 2019), suggesting that aragonite undersaturation will not cause complete dissolution and total loss of habitat.

Sensitivity Assessment. As squat lobsters such as Munida sp. rely on coral rubble for provision of heterogeneous habitat, they are likely to be impacted by the dissolution of the rubble and simplification of the habitat. There is evidence that some squat lobsters, including species from the genus Munida, live at depths where the aragonite saturation state is < 1, and this genus is therefore expected to be tolerant to ocean acidification. Therefore, under the middle emission scenario (0.15 unit decrease in pH), the aragonite saturation horizon (ASH) is not expected to reach the upper bathyal (200-600 m) or the shelf seas (<200 m)  (Zheng & Long, 2014), and hence Lophelia pertusa rubble is not expected to suffer any dissolution. Therefore, resistance is assessed as ‘High’, resilience as ‘High’ and sensitivity is assessed as ‘Not sensitive’ at this benchmark.  Under the high emission scenario (0.35 unit decrease in pH), the ASH saturation state is predicted to rise to approximately 400 m, reaching the upper bathyal, and could lead to some dissolution of the coral rubble and a reduction in habitat structure, although it is likely that the squat lobsters themselves will be tolerant of this reduction in pH.  Therefore, resistance has been assessed as ‘Medium’ as it is assumed that sufficient habitat would remain to support the squat lobster assemblage.  Resilience has been assessed as ‘Very Low’ due to the long-term nature of ocean acidification, and, hence, sensitivity is assessed as ‘Medium’. 

The absorption of carbon dioxide from the atmosphere and the resultant decrease in pH leads to changes in the carbonate chemistry of the oceans; an increase in hydrogen ions and a decrease in carbonate ions, which are needed for calcification. When the aragonite saturation state falls below 1, shells, coral skeleton, and other aragonitic structures start to dissolve.  This results in the shoaling of the aragonite saturation horizon (ASH). The ASH is defined as the depth in the oceans at which aragonite saturation equals 1. Below this depth, the aragonite saturation state (Ω_Ar) will fall below 1, and dissolution of calcified structures that are not protected by living tissue (e.g. coral reef and fragments) may occur. Currently, the depth of the ASH in the North Atlantic is approximately 2000m (Jiang et al., 2015) but this depth is already 80-150 m shallower than the past two centuries (Chung et al., 2003, Feely et al., 2004). By the end of this century, the ASH is expected to reach depths of up to 400 m under the high emission scenario (RCP 8.5) and 600 m for the middle emission scenario (RCP 4.5) (Zheng & Long, 2014).

Little is known of the effects of ocean acidification on squat lobsters, although at a submarine canyon off the coast of Australia, Munidopsis sp. has been found living at depths of 1357 m, >300 m below the ASH (Trotter et al., 2019). Whilst this is the only literature which describes the depth of a squat lobster in relation to the aragonite saturation state, the fact that species from the genus Munida are found at depths of more than 3000 m suggests that this genus is likely to be robust to future ocean acidification, even if the ASH does rise to the upper bathyal.

The abundance of squat lobsters is most likely intrinsically linked to the heterogeneity of the coral rubble and gravel in which this group of animals resides within this biotope. Squat lobsters often have a symbiotic lifestyle with their habitat and two species are commonly associated with Lophelia pertusa reef and rubble; Munida rugosa and Munidopsis serricornis (Baeza, 2011). Habitat complexity mediates predator-prey interactions through the provision of refuges (Rogers et al., 2014), and there is a strong positive relationship between complexity and species density and biomass (Graham & Nash, 2013). For Lophelia pertusa, both areas of live coral and areas of coral rubble enhance species density, compared to areas with no coral framework (Jonsson et al., 2004).

In an experiment, Voight (2010) looked at the dissolution of dead Lophelia pertusa rubble fragments in response to different aragonite saturation states. After 50 days, minimal dissolution was seen at Ω_Ar 1.02, but dissolution became more apparent at Ω_Ar 0.71 – 0.55 (Voigt, 2010). Furthermore, Hennige et al. (2015) observed dissolution of the exposed skeleton at aragonite saturation states < 1 and found that Lophelia pertusa coral framework became 20-30% weaker at low pH, even before saturation state fell below 1 (Ω_Ar 1.19-1.09). Extensive coral graveyards have been observed below the aragonite saturation horizon in Australia, which are thought to have flourished during the last ice age 18 – 33 thousand years ago (Trotter et al., 2019), suggesting that aragonite undersaturation will not cause complete dissolution and total loss of habitat.

Sensitivity Assessment. As squat lobsters such as Munida sp. rely on coral rubble for provision of heterogeneous habitat, they are likely to be impacted by the dissolution of the rubble and simplification of the habitat. There is evidence that some squat lobsters, including species from the genus Munida, live at depths where the aragonite saturation state is < 1, and this genus is therefore expected to be tolerant to ocean acidification. Therefore, under the middle emission scenario (0.15 unit decrease in pH), the aragonite saturation horizon (ASH) is not expected to reach the upper bathyal (200-600 m) or the shelf seas (<200 m)  (Zheng & Long, 2014), and hence Lophelia pertusa rubble is not expected to suffer any dissolution. Therefore, resistance is assessed as ‘High’, resilience as ‘High’ and sensitivity is assessed as ‘Not sensitive’ at this benchmark.  Under the high emission scenario (0.35 unit decrease in pH), the ASH saturation state is predicted to rise to approximately 400 m, reaching the upper bathyal, and could lead to some dissolution of the coral rubble and a reduction in habitat structure, although it is likely that the squat lobsters themselves will be tolerant of this reduction in pH.  Therefore, resistance has been assessed as ‘Medium’ as it is assumed that sufficient habitat would remain to support the squat lobster assemblage.  Resilience has been assessed as ‘Very Low’ due to the long-term nature of ocean acidification, and, hence, sensitivity is assessed as ‘Medium’. 

At a depth of 200 – 600 m, these biotopes will not be affected by sea-level rise.  Therefore sensitivity to this climate change pressure is probably ‘Not relevant’ in this bathyal habitat.

At a depth of 200 – 600 m, these biotopes will not be affected by sea-level rise.  Therefore sensitivity to this climate change pressure is probably ‘Not relevant’ in this bathyal habitat.

At a depth of 200 – 600 m, these biotopes will not be affected by sea-level rise.  Therefore sensitivity to this climate change pressure is probably ‘Not relevant’ in this bathyal habitat.

Not assessed

Not assessed

Not assessed

Not assessed

Not assessed