Species diversity and spatial distribution of pelagic amphipods in Terra Nova Bay (Ross Sea, Southern Ocean)

Abstract A greater understanding of biodiversity and the roles various species involved in Southern Ocean pelagic food webs is needed to predict hypothesize about responses future scenarios relation climate changes. The aim this paper was describe for first time composition, relative abundance, spatial distribution with water masses amphipods Terra Nova Bay, Ross Sea, based on stratified sampling. Zooplankton collected by BIONESS (Bedford Institute Oceanography Net Environmental Sampling System), during 1987–1988 Italian Antarctic R/V Polar Queen Expedition. total 1331 specimens counted 17 belonging nine families were identified. Significantly higher abundances related Modified Circumpolar Deep Water (MCDW) upper layer than modified Sea Shelf (RSSW) High Salinity (HSSW). Hyperiella dilatata most abundant (48% abundance), followed Pseudorchomene plebs (14%), Hyperia macrocephala (8%) macronyx (6%). distributed widely across study area showed a link Surface Waters (AASW) MCDW. rossi also though much lower abundance. high abundance had narrow that linked AASW. vertical distributions variable patterns adult juvenile specimens. This represents knowledge base against which compare more recent studies highlight any structural changes attributable ongoing change Bay ecosystems.