BIOTIC Species Information for Gammarus salinus
|Researched by||Georgina Budd||Data supplied by||MarLIN|
|Refereed by||This information is not refereed.|
|Scientific name||Gammarus salinus||Common name||A gammarid shrimp|
|MCS Code||S481||Recent Synonyms||None|
|Taxonomy References||Lincoln, 1979, Hayward et al., 1996, Ruppert & Barnes, 1994, Kolding, 1981,|
Surface deposit feeder
|Typical food types||Organic detritus and seaweed.||Habit||Free living|
|Bioturbator||Not relevant||Flexibility||High (>45 degrees)|
|Height||Insufficient information||Growth Rate||Insufficient information|
|Adult dispersal potential||100-1000m||Dependency||Independent|
|General Biology Additional Information||Moulting
Kinné (1960) found that the frequency (days - weeks) at which Gammarus salinus moulted varied with changes in temperature, the intervals being longer in males than in females. Females kept without a male showed a progressive prolongation of the intervals between moults beginning with the 3rd of 4th interval following isolation. Females kept together with males, in pairs, maintained moults at constant intervals. No differences were observed to occur in different salinities of 5, 10 and 30 psu.
|Biology References||Lincoln, 1979, Kinné, 1960, Breeman & Hoeksema, 1987,|
|Distribution and Habitat|
|Distribution in Britain & Ireland||On all coasts of England, Scotland and Wales in brackish-water, especially in the Humber and Severn Estuaries.|
|Global distribution||North-west Europe from English Channel to Baltic, some isolated reports of Gammarus salinus on the Iberian Peninsula.|
|Biogeographic range||Not researched||Depth range||0-10 m|
|Migratory||Non-migratory / Resident|
|Distribution Additional Information||Gammarus species are abundant estuarine animals. Spooner (1947) stated that gammarids were adaptable to various surroundings and not limited to particularly specialised ecological niches. Nor did they show gross patchiness of distribution within their habitable range, rather continuous populations occupy the entire length of estuaries, although the proportion of species represented changes from head to mouth. Furthermore, gammarids are relatively indifferent to the nature of the substratum to a remarkable degree. Provided that there is some kind of object to provide them with shelter/cover it does not matter whether the substratum is muddy or stony, the water turbid or clear and almost any kind of organic matter provides detritus upon which to feed (Spooner, 1947).
The distributional range of Gammarus salinus to the south was thought to be restricted as far as the English Channel. However, Van Maren (1975) reported Gammarus salinus for the first time on the Spanish coast in 1974.
Gravel / shingle
Coarse clean sand
|Biological zone||Upper Infralittoral
|Tidal stream strength/Water flow||Strong (3-6 kn)
Moderately Strong (1-3 kn)
|Salinity||Reduced (18-30 psu)
Low (<18 psu)
|Habitat Preferences Additional Information|
|Distribution References||Lincoln, 1979, JNCC, 1999, NBN, 2002, Maren van, 1975, Crothers, 1966, Spooner, 1947,|
||Developmental mechanism||Direct Development
|Reproductive Season||Autumn to spring||Reproductive Location||Insufficient information|
|Reproductive frequency||Annual protracted||Regeneration potential||No|
|Life span||<1 year||Age at reproductive maturity||<1 year|
|Generation time||<1 year||Fecundity||Increases with female length|
|Egg/propagule size||Insufficient information||Fertilization type||Internal|
|Reproduction Preferences Additional Information||Leineweber (1985) sampled a population of Gammarus salinus over 15 months in the south-western Kattegat at Sangstrup Klint, Denmark and reported that Gammarus salinus most likely had two generations per year, mature females were found from late November to late July. However, in the Limfjord, Denmark, the population of Gammarus salinus was reported to only produce one generation between 1977-1978, despite the presence of egg bearing females throughout the year (Kolding & Fenchel, 1979). Juveniles were most numerous from April through to July, and in the warmer months between July and October a relatively stable population was attained. The main reproduction period occurred during the winter months, with 80% of the female population reported to be pregnant, the adult generation died in May.
During reproduction, the male carries the smaller female grasped by his gnathopods, a condition known as amplexus. The animals separate briefly to permit the final preadult moult of the female. Sperm transfer is accomplished quickly; the male twists his abdomen around so that his uropods touch the female marsupium (brood pouch) and sperm are swept into the marsupium by the ventilating current created by the female. Finally the pair separate (Rupert & Barnes, 1994). The eggs are brooded within a chamber, the marsupium, beneath the thorax, formed by shelf-like plates projecting inward from the thoracic coxae.
Kinné (1960) examined the effects of different temperatures and salinity on the incubation time of Gammarus salinus. At a temperature between 19-20 °C females attained sexual maturity (1st oviposition) 20-30 days after hatching; their average length (from tip of rostrum to base of telson) being 7-8 mm. Males reached maturity one or more weeks later than the females. The incubation time (period between oviposition and hatching) of the eggs depended largely on the temperature at which the females were maintained; < 14 °C incubation took over 15 days and decreased to 5 days at 20 °C. As in other amphipods Kinné (1960) found that the fecundity of females increased with length, with numbers of eggs varying in a clutch (Ruppert & Barnes, 1994).
|Reproduction References||Leineweber, 1985, Kinné, 1960, Ruppert & Barnes, 1994, Kolding & Fenchel, 1979,|