Pectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand

07-08-2002
Researched byGeorgina Budd Refereed byThis information is not refereed.
EUNIS CodeA2.112 EUNIS NamePectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand

Summary

UK and Ireland classification

EUNIS 2008A2.112Pectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand
EUNIS 2006A2.112Pectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand
JNCC 2004LS.LCS.Sh.PecPectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand
1997 BiotopeLS.LGS.Sh.PecPectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand

Description

Shores of well-sorted gravel with a predominant particle size of 4 mm but ranging between 3 and 6 mm may support populations of the amphipod Pectenogammarus planicrurus. Material finer than 2 mm reduces the ability of the amphipod to survive. The biotope is often associated with the lee side of obstacles such as rock outcrops and groynes; this may be due to the deposition of algal debris, shelter from wave action or degree of sorting due to localised tidal flow around the obstacle (most likely a combination of the first and last influences). The biotope is characterized by dense populations of the amphipod Pectenogammarus planicrurus, although the species is usually also present as patchy populations within the mid shore band of other moderately wave-exposed sandy shore biotopes (e.g. LGS.Tal - Talitrid amphipods in decomposing seaweed on the strand-line, LGS.AP - Burrowing amphipods and polychaetes in clean sand shores). The amphipod is tolerant of variable salinity, although a preference for a specific salinity regime has not been determined. As this habitat is regularly under-surveyed, its distribution is unclear and may be a variant of LGS.Tal demonstrated by the similarity of species found and presence of strand material. (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Recorded distribution in Britain and Ireland

A localized and patchy biotope, that is represented on the English Channel coast between Brighton, Sussex and Deal, Kent, and at locations around Aberystwyth, on the west coast of Wales. Other locations include, Eype in Dorset, Penzance, Cornwall, the Isle of Man and east, south and west coasts of Ireland.

Depth range

Mid shore, Upper shore

Additional information

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JNCC

Habitat review

Ecology

Ecological and functional relationships

  • Species diversity is influenced by habitat stability and sediment type. The apparent harshness of the coarse sand/gravel beach environment belies the rich rewards for an organism capable of withstanding the rigours. There is an almost complete lack of competing species, a relative absence of predators (although the predatory isopod Eurydice pulchra may frequent the biotope as part of the surf plankton and prey upon Pectenogammarus planicrurus (Naylor, 1972), and an abundant supply of food in the form of macroalgae and other organic debris (Bell, 1995).
  • A critical relationship exists between the size of interstitial spaces in the substratum through which the species can pass and the size of Pectenogammarus planicrurus (Morgan, 1970). Selection experiments carried out with particles retained by 6.35, 3.35, 2.06 and 1.4 mm sieves revealed a clear preference for the 3.35 mm grade of particles. Further experiments showed that the passage of Pectenogammarus planicrurus was impaired by particles of the grade 2.06 mm, below which mortalities occurred. Following further work, Bell (1992) concluded that particle size was more important in determining the nature of the population of Pectenogammarus planicrurus than any other aspect of shore location, such as shore level (within tidal limits) and depth within the substratum. Bell (1992) consequently stated substratum preferences to be an important factor driving the population dynamics of the species, causing size-dependent migration between different grades of gravel. Short distance migration was suggested to be one reason why Pectenogammarus planicrurus enters the surf plankton (Morgan, 1968; Fincham, 1970; Bell, 1992).

Seasonal and longer term change

Episodes of substratum instability would be expected particularly during the winter owing to storm generated wave action. In the calmer conditions that follow storm events, considerable quantities of macroalgal detritus are deposited on the gravel beach. Other macrofaunal species not especially found in the biotope may appear and exploit the food resource, these include archianellids of the genus Protodrilus, idoteid isopods and a variety of gammaridean amphipods, e.g. Atylus swammerdami and Gammarus salinus (Bell, 1995).

Habitat structure and complexity

Where coarse sand and gravel beaches originate from relict glacial deposits, the particles are smooth and of a similar size, whilst very coarse particle beaches derived from the erosion of cliffs are more mixed and angular in shape. Coarse particle beaches are also likely to be found in wave exposed conditions where they are continually disturbed by plunging breakers. The beach is inherently unstable and the moving particles crush and grind against each other so that the surfaces are devoid of life other than microscopic species. The gaps between the particles are large so that on the ebbing tide water drains freely away because the capillary forces which hold on to the water are weak. It is in this interstitial space that the amphipod Pectenogammarus planicrurus lives. An important process along many coasts is the along-shore displacement of sediment or 'longshore drift'. As a coastal protection measure, barriers to longshore drift, 'groynes', are placed at right angles to the shore in the lee of which subsidiary currents are created which create a degree of substrate sorting and macroalgal debris deposited. Pectenogammarus planicrurus may be particularly abundant behind such obstructions to the current.

Productivity

Very coarse sandy beaches are extremely unstable places, consequently macrophyte species do not become established owing to the lack of a stable substratum. In most situations, diatoms are the primary producers of the depositing shore, and are confined to the illuminated sediment surface layers. The phytoplankton of the sea also become a temporary part of the shore ecosystem when the tide is in and primary producers from other environments appear on the shore. These are invariably macroalgae that have become detached from rocky substrata and have been washed up, eventually they decompose on the beach and contribute to the energy budget of the shore system. Consequently most productivity on the depositing sandy shore may be categorised as secondary, derived from detritus and allochthonous organic matter, which is utilized by the fauna.

Recruitment processes

The amphipod, Pectenogammarus planicrurus, is the only species that is a permanent resident of the biotope and restricted to breeding within it. Other species, Eurydice pulchra and Gammarus salinus, may also be recorded in the biotope but are not faithful to it (see MarLIN reviews). On the west coast of Wales, Pectenogammarus planicrurus is an iteroparous breeder, with a semi-annual life history pattern (i.e. young produced early in the year mature and reproduce within the same year) and multiple overlapping generations (Bell, 1992). Females reach sexual maturity when body length is between 3-6 mm, and fecundity is related to female body size, ranging from 2 eggs per brood in small females to 14 per brood in large females. Mean brood size is 6.74 eggs (Bell & Fish, 1996). During the summer, the population turnover of Pectenogammarus planicrurus is high; a female might typically live for four weeks whilst those that survive and over-winter may live as long as eight months (Bell, 1992). For populations to persist in the harsh gravel/coarse sand beach, the species requires a high reproductive output at the population level, thus small brood sizes (brood sizes are typically larger in other species of intertidal amphipod) are compensated for by an early maturation and optimisation of reproductive trade offs, such as those between fecundity, egg size and parental female survival (Bell & Fish, 1996).

Time for community to reach maturity

Beaches are dynamic environments, even when they are neither gaining nor losing sediment they are subject to short-term changes in response to wave regimes and weather conditions. Beach profiles show alteration as beach-face sands are re-cycled and decline as the component sand grains are reduced in calibre by attrition and weathering. As a consequence of the dynamic nature of the habitat the faunal component of the biotope is very sparse and low in species richness. Therefore, the community might be considered 'mature' only a few days or weeks after the last storm event, as the mobile species displaced from the biotope and those from adjacent area colonize the substratum via the surf plankton.

Additional information

No text entered.

Preferences & Distribution

Recorded distribution in Britain and IrelandA localized and patchy biotope, that is represented on the English Channel coast between Brighton, Sussex and Deal, Kent, and at locations around Aberystwyth, on the west coast of Wales. Other locations include, Eype in Dorset, Penzance, Cornwall, the Isle of Man and east, south and west coasts of Ireland.

Habitat preferences

Depth Range Mid shore, Upper shore
Water clarity preferences
Limiting Nutrients Not relevant
Salinity Full (30-40 psu), Variable (18-40 psu)
Physiographic Enclosed coast / Embayment, Open coast
Biological Zone Eulittoral
Substratum Gravel / shingle, Coarse clean sand
Tidal
Wave Moderately exposed
Other preferences Gravel/shingle substratum

Additional Information

The habitat is under-surveyed, so may be more widespread than records suggest.

Species composition

Species found especially in this biotope

  • Pectenogammarus planicrurus

Rare or scarce species associated with this biotope

  • Pectenogammarus planicrurus

Additional information

No text entered.

Sensitivity reviewHow is sensitivity assessed?

Explanation

Pectenogammarus planicrurus has been identified as the important characterizing species of coarse sand/gravel biotopes, to which it is wholly faithful. Coarse sand/gravel beaches are shifting, unstable environments and consequently species diversity is very low. Other species that may be recorded include isopods, e.g. Eurydice pulchra and amphipods such as Gammarus salinus, which are likely to be carried in on the surf plankton and temporarily stranded. They are transitory and not faithful to the biotope. The biotope would still be recognized in the absence of species other than Pectenogammarus planicrurus.

Species indicative of sensitivity

Community ImportanceSpecies nameCommon Name
Important characterizingPectenogammarus planicrurusAn amphipod

Physical Pressures

 IntoleranceRecoverabilitySensitivitySpecies RichnessEvidence/Confidence
High Very high Low Major decline Moderate
The amphipod Pectenogammarus planicrurus live interstitially in the spaces between coarse sand/gravel particles. It is mobile within the substratum and would removed along with the substratum. Intolerance has been assessed to be high.
In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995)so, assuming that a proportion of the population survived in the locality, recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. A recoverability of very high has been recorded. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
High Very high Low Decline High
Pectenogammarus planicrurus is likely to be highly intolerant of smothering by 5 cm of sediment not consistent with that of the biotope. There is a critical relationship between the size of interstitial spaces in the substratum through which the species can pass and the size of Pectenogammarus planicrurus (Morgan, 1970). In selection experiments, the species demonstrated a clear preference for a sediment grades between 3-6 mm in diameter. Its passage through finer grades of substratum (<3mm) was impaired and mortalities occurred as a consequence of suffocation. Intolerance has been assessed to be high.
Siltation may occur as a consequence of increased suspended sediment in the water column and reduced water movement (tidal and wave action) and is also likely to have a smothering effect on the amphipod.
In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995) so, assuming that a proportion of the population survived in the locality, recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are consequently isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
Not relevant Not relevant Not relevant Not relevant Not relevant
Pectenogammarus planicrurus lives in the interstitial spaces within coarse sand/gravel and is unlikely to be directly affected by an increased concentration of suspended matter in the water column. However, the effects of siltation (settling out) of such material has been assessed under smothering (see above).
Not sensitive* Not relevant Moderate
Pectenogammarus planicrurus lives in the interstitial spaces within coarse sand/gravel and is unlikely to be directly affected by a decrease in the concentration of suspended matter in the water column. The factor was not considered relevant.
Not relevant Not relevant Not relevant Not relevant Not relevant
Pectenogammarus planicrurus lives interstitially in the coarse sand/gravel substratum. Its environmental position would therefore offer considerable protection against desiccation. Furthermore, the species is mobile within the substratum and may burrow deeper should the uppermost layers become too dry. At the benchmark level desiccation was not considered to be relevant.
Tolerant Not relevant Not relevant No change Low
Pectenogammarus planicrurus lives interstitially within the coarse sand/gravel and is probably sufficiently mobile within it to avoid adverse effects of a change in emergence regime. For instance it can burrow deeper to avoid dryer surface layers. At the benchmark level an assessment of not sensitive has been made.
Tolerant Not sensitive* No change Low
Pectenogammarus planicrurus lives interstitially within the coarse sand/gravel and is probably sufficiently mobile within it to avoid adverse effects of a change in emergence regime. At the benchmark level an assessment of not sensitive has been made.
Tolerant* Not relevant Not sensitive* Not relevant Moderate
The nature of the substratum that Pectenogammarus planicrurus inhabits is determined by both wave action and water flow, although wave action may be particularly significant in terms of substratum stability. Both factors will influence the degree of sorting of the substratum. The species thrives in well-sorted sediment, with particles of a diameter between 3-6 mm (Morgan, 1970). Increased water flow rate may serve to increase the extent of available habitat by removing finer particulate matter, which is know to inhibit the movement of Pectenogammarus planicrurus and cause mortalities (Morgan, 1970). An assessment of not sensitive* has been made.
High Very high Low Decline Moderate
Wave action is likely to a more important factor than water flow rate in determining the nature of the substratum that Pectenogammarus planicrurus inhabits. Decreased water flow is unlikely to have any adverse effects on the species and an assessment of not sensitive has been made.
Low Immediate Not sensitive No change Low
Pectenogammarus planicrurus is found to the south of the British Isles so is likely to be tolerant of a chronic temperature increase of 2°C. No evidence was found concerning the species tolerance to acute temperature increases, however, as the species lives interstitially within the coarse sand/gravel substratum it may be protected to some extent by acute temperature increases at the surface. An intolerance assessment of low has been made as in avoiding higher surface temperatures the feeding efficiency of the species may be impaired (i.e. algal detritus deposited on the surface of the substratum). Recovery is likely to be immediate once surface temperatures decrease.
Intermediate Very high Low Decline Low
Records of Pectenogammarus planicrurus have not been reported to the north of the British Isles. Bell (1995) suggested that the northerly limit to the distribution of Pectenogammarus planicrurus is defined by the lowest temperature at which its life history is possible (see recruitment processes). A chronic decrease of 2°C may therefore affect the viability of the species.
Furthermore, in the intertidal acute decreases in temperature, e.g. during a severe winter, may cause freezing of the species within the substratum. Intolerance has been assessed to be intermediate, as a proportion of the population may be killed.
In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995), so assuming that a proportion of the population survived in the locality recovery might be reasonably expected to occur within a year following a return to prior conditions. A recoverability of very high has been recorded. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely killed recovery may take considerably longer.
Not relevant Not relevant Not relevant Not relevant Not relevant
The light attenuating effects of an increase in turbidity are unlikely to directly affect Pectenogammarus planicrurus. However, particles in suspension causing turbidity may have an indirect effect should they settle out. The effects are addressed under suspended sediment. An intolerance assessment was not considered relevant.
Not sensitive* Not relevant
Pectenogammarus planicrurus is unlikely to be affected by a reduction in turbidity in the water column as it is an interstitial species.
High Very high Low Decline Low
Wave exposure is an important physical factor determining the composition of the substratum and its stability. Typically the biotope experiences moderate wave exposure. Increased wave exposure, so that the biotope experienced very wave exposed conditions over a period of a year would probably cause concomitant changes in the nature of the beach substratum. Smaller particles may be eroded or transported off the beach, leaving a much coarser grained substratum.
There is a critical relationship between the size of interstitial spaces in the substratum through which the species can pass and the size of Pectenogammarus planicrurus (Morgan, 1970). In selection experiments, the species demonstrated a clear preference for a sediment grades between 3-6 mm in diameter. Its passage through finer grades of substratum (<3mm) was impaired and mortalities occurred as a consequence of suffocation. Mortalities as a direct result of a much coarser substratum are unlikely, rather the interstitial environment (in terms of desiccation, food retention) may change significantly and the species be exposed to conditions outside of its preference and from which it will move. Intolerance to increased wave exposure has been assessed to be high.
In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995) so, assuming that a proportion of the population survived in the locality, recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are consequently isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
High Very high Low Decline Moderate
The amphipod, Pectenogammarus planicrurus is most abundant in well-sorted gravel with a predominant particle size of 4.0 mm but ranging between 3 and 6 mm and wave action is an important factor determining the degree of sorting of the substratum. In the event of decreased wave action the degree of sorting is likely to lessen and finer particulates occur in the substratum. There is a critical relationship between the size of interstitial spaces in the substratum through which the species can pass and the size of Pectenogammarus planicrurus (Morgan, 1970). In selection experiments, the species demonstrated a clear preference for a sediment grades between 3-6 mm in diameter. Its passage through finer grades of substratum (<3mm) was impaired and mortalities occurred as a consequence of suffocation.
It is likely that following a decrease in wave exposure over a year, that the important characterizing species of the biotope, Pectenogammarus planicrurus, would be exposed to conditions outside its habitat preferences and from which it would be excluded and would have to move elsewhere in order to survive. Some mortalities may occur owing to inhibition of movement and smothering. Intolerance has been assessed to be high.
In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995), so assuming that a proportion of the population survived recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are consequently isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
Tolerant Not relevant Not relevant No change Low
Pectenogammarus planicrurus is unlikely to be able to detect noise at the benchmark level, so an assessment of not sensitive has been made.
Tolerant Not relevant Not relevant No change Low
Pectenogammarus planicrurus lives interstitially and probably lacks the visual acuity to detect movement outside of its visual plane. An assessment of not relevant has been made.
Tolerant Not relevant Not relevant No change Moderate
The biotope in which Pectenogammarus planicrurus lives is characterized by a high level of physical disturbance attributable to wave action. The important characterizing species is small, lives interstitially and is not of a form that is likely to be damaged by abrasion at the benchmark level. This biotope is characteristic of physically disturbed coarse sands and gravels, so that the habitat and its associated community is likely to be tolerant of physical disturbance and abrasion. Severe physical disturbance, for example due to extreme storms or extraction of the substratum will have the same effect as substratum loss discussed above.
Not relevant Not relevant Not relevant Not relevant Not relevant
The fauna of this biotope are not physically attached to the substratum and can not therefore be displaced. A sensitivity assessment was not considered relevant.

Chemical Pressures

 IntoleranceRecoverabilitySensitivityRichnessEvidence/Confidence
High Very high Low Decline Low
No information concerning synthetic chemical and specific effects on the important characterizing species, Pectenogammarus planicrurus, was found.
However, areas of the intertidal adjacent to industrialised and urbanised estuaries and coastlines may receive effluent discharges which contain a variety of synthetic contaminants. Bioaccumulation of conservative contaminants may occur within the infauna, but in coarse sand/gravel beaches contaminants are unlikely to accumulate owing to a relative absence of organic matter. Direct toxic effects would therefore be expected. In general, crustaceans are widely reported to be intolerant of synthetic chemicals (Cole et al., 1999) and intolerance to some specific chemicals has been observed in amphipods. Powell (1979) inferred from the known susceptibility of Crustacea to synthetic chemicals and other non-lethal effects, that there would probably also be a deleterious effect on isopod fauna as a direct result of chemical application. Toxicity tests conducted by Smith (1968), indicated that survival of Eurydice pulchra after oil detergent treatment was above average for crustaceans. All were killed at about 10 ppm BP 1002 after 24 hours exposure, whilst at 5 ppm four out of five individuals survived when transferred to clean sea water.
Species of a different genus are likely to differ in their susceptibility to synthetic chemicals and that this may be related to differences in their physiology (Powell, 1979). Consequently, in the absence of evidence to the contrary and owing to the diversity of synthetic chemicals to which the biotope may be exposed, intolerance has been assessed to be high. Recovery assumes dilution, biodegradation or removal of the contaminant from the sediments. In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995) so, assuming that a proportion of the population survived in the locality, recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
Heavy metal contamination
Intermediate Very high Low Decline Low
No information concerning heavy metals and specific effects on Pectenogammarus planicrurus, was found. For most metals, toxicity to crustaceans increases with decreased salinity and elevated temperature, therefore marine species living within their normal salinity range may be less susceptible to heavy metal pollution than those living in salinities near the lower limit of their salinity tolerance (McLusky et al., 1986). Intolerance has been assessed to be intermediate specifically because alterations in salinity and temperature influence the effect of heavy metals on the important characterizing species. The entire population may not be destroyed but may experience sublethal effects which may reduce the viability of the population. Recovery assumes removal of the contaminant from the biotope. In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995) so, assuming that a proportion of the population survived in the locality, recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
Hydrocarbon contamination
High Very high Low Major decline Moderate
Pectenogammarus planicrurus is likely to have a high intolerance to hydrocarbon pollution. Oil penetrates deep in to coarse sand/gravel substratum. For example, the largest amount and least weathered oil arising from the Exxon Valdez oil tanker spill in Prince William Sound, Alaska was found eight years after the incident on gravel beaches at a depth between 25 and 50 cm (Hayes & Michel, 1999). Moderate wave exposure and unstable substratum characteristic of the biotope probably aid the penetration of oil in to the sediment. The smothering effect of oil is likely to cause mortality of Pectenogammarus planicrurus in advance of toxic effects. Oil would coat the substratum particles, lessening the interstitial voids through which the amphipod moves and to which it would probably stick. Intolerance has been assessed to be high. Recovery assumes removal of the contaminant from the biotope. In order to survive in the harsh gravel/coarse sand habitat the species has a high reproductive output at the population level (Bell, 1995), so assuming that a proportion of the population survived in the locality recovery might be reasonably expected to occur within a year following a return to prior conditions and good sorting of the beach substratum. However, the reported distribution of Pectenogammarus planicrurus is patchy, as is the occurrence of coarse sand/gravel, and populations are isolated. No information was found concerning the exchange of Pectenogammarus planicrurus between populations. Consequently, if a population was completely removed recovery may take considerably longer.
Radionuclide contamination
No information Not relevant No information Not relevant Not relevant
Insufficient
information.
Changes in nutrient levels
Tolerant* Not relevant Not sensitive* Not relevant Moderate
Pectenogammarus planicrurus feeds on macroalgae carried in from elsewhere by the tide and deposited on the shore, it is also thought probable that the species is capable of feeding on suspended particles and phytoplankton in the intertidal waters (J.D. Fish & L. Rickard pers. comm. to Bell, 1995). Consequently the species may benefit indirectly from an increase in the dissolved nutrient concentration of the water column, as a food resource, phytoplankton, may increase in abundance as a result. An assessment of not sensitive* has been made.
Not relevant Not relevant Not relevant Not relevant Not relevant
Pectenogammarus planicrurus lives in the intertidal in conditions of full salinity. In its habitat the species is unlikely to encounter hypersaline water (e.g. as a consequence of evaporation of 'pooled' surface water) as the substratum is very permeable and free draining. An intolerance assessment of not relevant has been made.
Tolerant Not sensitive* Not relevant Moderate
Experimental evidence suggests that Pectenogammarus planicrurus can withstand immersion in water of reduced salinity (20 psu) for 36 hours and freshwater for >18 hours (Morgan, 1970). Thus it is likely that the important characterizing species of the biotope would survive periodic flushing of the sediment with brackish or fresh water. As a mobile species it would also probably move from conditions which it found intolerable, so mortality is unlikely. An assessment of not sensitive has been made.
Not relevant Not relevant Not relevant Not relevant Not relevant
In its intertidal habitat Pectenogammarus planicrurus is inundated by the tide and subject to emergence so, it is presumed that the species can live in both air and water. Within the interstitial environment of clean (low organic matter), coarse sand/gravel oxygen is unlikely to become limiting. The coarseness of the particles, bestows a high permeability, so that water percolates rapidly through and owing to the relative lack of organic matter, little oxygen is utilized for oxidization or respiration by micro-organisms (bacteria populations in sediments with a mean diameter greater than 0.2 mm typically support fewer bacteria (Dale, 1974)). Oxygen depletion tends to be a severe problem at all states of the tide on much finer grained beaches which support larger populations of bacteria (Hayward, 1994). At the benchmark level (a reduced dissolved oxygen concentration of 2 mg/l for 1 week) an assessment of not relevant has been made, primarily because the characteristics of the habitat make conditions of limiting oxygen unlikely and secondly, the important characterizing species, Pectenogammarus planicrurus, is sufficiently mobile to avoid conditions that it finds inhospitable.

Biological Pressures

 IntoleranceRecoverabilitySensitivityRichnessEvidence/Confidence
No information No information No information Not relevant Not relevant
No information was found concerning the effects of microbial pathogens on the species colonizing this biotope.
Not relevant Not relevant Not relevant Not relevant Not relevant
No alien species are know to have adverse effects on the species colonizing this biotope.
Not relevant Not relevant Not relevant Not relevant Not relevant
It is extremely unlikely that the species indicative of sensitivity would be targeted for extraction and we have no evidence for the indirect effects of extraction of other species on this biotope.
Not relevant Not relevant Not relevant Not relevant Not relevant

Additional information

No text entered.

Importance review

Policy/Legislation

- no data -

Exploitation

Coastal erosion may be exacerbated by offshore dredging, as both the roads infrastructure programme and construction industry are heavily dependent on supplies of marine aggregates. Sourcing aggregates from marine deposits is increasingly seen as a means to partially meet such demands. The full impact of offshore dredging is unknown but it is implicated in starving the coast of the sediment needed for beach building (Hubbard & MacGuire, 1997).

Additional information

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Bibliography

  1. Bell, M.C. & Fish, J.D., 1996. Fecundity and seasonal changes in reproductive output of females of the gravel beach amphipod Pectenogammarus planicrurus. Journal of the Marine Biological Association of the United Kingdom, 76, 37-55.
  2. Bell, M.C., 1992. The ecology of the gravel beach amphipod Pectenogammarus planicrurus Reid. PhD thesis, University of Wales., PhD thesis, University of Wales.
  3. Bell, M.C., 1995. Pectenogammarus planicrurus - there is life in gravel beaches. Porcupine Newsletter, 6, 41-47.
  4. Cole, S., Codling, I.D., Parr, W. & Zabel, T., 1999. Guidelines for managing water quality impacts within UK European Marine sites. Natura 2000 report prepared for the UK Marine SACs Project. 441 pp., Swindon: Water Research Council on behalf of EN, SNH, CCW, JNCC, SAMS and EHS. [UK Marine SACs Project.], http://www.ukmarinesac.org.uk/
  5. Connor, D.W., Brazier, D.P., Hill, T.O., & Northen, K.O., 1997b. Marine biotope classification for Britain and Ireland. Vol. 1. Littoral biotopes. Joint Nature Conservation Committee, Peterborough, JNCC Report no. 229, Version 97.06., Joint Nature Conservation Committee, Peterborough, JNCC Report No. 230, Version 97.06.
  6. Dale, N.G., 1974. Bacteria in intertidal sediments: factors related to their distribution. Limnology and Oceanography, 19, 509-518.
  7. 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.
  8. Duhig, M. & Humphries, C., 1955. Amphilochus brunneus Della Valle, an amphipod new to Britain and Ireland and notes on other amphipods not previously recorded in Irish coastal waters, Proceedings of the Royal Irish Academy (B), 57, 123-129.
  9. Duhig, M., 1960. The Amphipoda of Dalkey Island and its neighbouring waters. Proceedings of the Royal Irish Academy (B), 61, 59-77.
  10. Fincham, A.A., 1970a. Amphipods in the surf plankton. Journal of the Marine Biological Association of the United Kingdom, 50, 177-198.
  11. Hays, M.O. & Michel, J., 1999. Factors determining the long-term position of Exxon Valdez oil in gravel beaches. Marine Pollution Bulletin, 38, 92-101.
  12. Hayward, P.J. 1994. Animals of sandy shores. Slough, England: The Richmond Publishing Co. Ltd. [Naturalists' Handbook 21.]
  13. 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,
  14. Jones, N.S., 1948b. The ecology of the Amphipoda of the Isle of Man. Journal of the Marine Biological Association of the United Kingdom, 24, 400-439.
  15. McLusky, D.S., Bryant, V. & Campbell, R., 1986. The effects of temperature and salinity on the toxicity of heavy metals to marine and estuarine invertebrates. Oceanography and Marine Biology: an Annual Review, 24, 481-520.
  16. Michel, J. & Hayes, M.O., 1999. Weathering patterns of oil residues eight years after the Exxon Valdez oil spill. Marine Pollution Bulletin, 38, 855-863.
  17. Morgan, E., 1968. The biology of Pectenogammarus planicrurus (Reid). PhD thesis, University of Wales., PhD thesis, University of Wales.
  18. Morgan, E., 1970. The effect of environmental factors on the distribution of the amphipod Pectenogammarus planicrurus, with particular reference to grain size. Journal of the Marine Biological Association of the United Kingdom, 50, 769-785.
  19. Powell, C.E., 1979. Isopods other than cyathura (Arthropoda: Crustacea: Isopoda). In Pollution ecology of estuarine invertebrates (ed. C.W. Hart & S.L.H. Fuller), 325-338. New York: Academic Press.
  20. Smith, J.E. (ed.), 1968. 'Torrey Canyon'. Pollution and marine life. Cambridge: Cambridge University Press.

Citation

This review can be cited as:

Budd, G.C. 2002. Pectenogammarus planicrurus in mid shore well-sorted gravel or coarse sand. In Tyler-Walters H. and Hiscock K. (eds) Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. Available from: http://www.marlin.ac.uk/habitat/detail/151

Last Updated: 07/08/2002