Feeding ecology in five shrimp species (Decapoda, Caridea) from an Arctic Fjord (Isfjorden, Svalbard), with emphasis on Sclerocrangon boreas (Phipps, 1774)

Analyses of stomach contents indicate diet specificity in the species of shrimps investigated. Eualus gaimardii displayed a mostly pelagic feeding habit by preying mainly on copepods and amphipods. However, high loads of sediment in the stomachs of E. gaimardii indicate that feeding also occurred in the vicinity of the sea floor. More epibenthic feeding behaviour was found in Lebbeus polaris, in which large amount of hydrozoans and amphipods were recorded in the stomach. Spirontocaris spinus showed the strongest affinity to foraminiferans and hydrozoans as prey items. In Sclerocrangon boreas, eight out of ten prey categories were recorded, which makes this the most opportunistic among the species considered. Male S. boreas were generally found at shallower depths than females. Females fed more on infaunal organisms, while males used epibenthic organisms as a food source. When dissimilarities in diet are considered at the two shallowest stations, there is a stronger effect of depth than of sex, indicating that faunal changes at different depths are more important for diet composition than the sex of an individual.