Characterization of the community of amphipods (Crustacea: Gammaridea) of the Antarctic intertidal

Dr Ana Verdi, Facultad de Ciencias

From the study of the biodiversity of crustaceans in Collins Bay, it has been verified that this community is dominated by gammarid amphipods. Gammarid amphipods are a group of small crustaceans that usually do not exceed 2 cm in size (except in Antarctica) and have a large capacity to camouflage themselves in the environment in which they live. They have a compressed body laterally, which gives them a chubby appearance. They are fundamentally part of the benthic communities of the intertidal pools, hollows within the rocky coasts in which a rich community of organisms that interact in complex form develops. They are continuously affected by the microclimatic changes produced as a result of the variation in the tide level, which originates different communities even in the same locality and with the remoteness of a few meters.

In the Antarctic ecosystem, they play a fundamental role in having occupied the place left by the decapods (crabs, lobsters, shrimp), which is reflected in their abundance, biomass and number of species. They feed on a wide variety of sources, ranging from matter in suspension, sediment, debris, algae, wood and even other animals or carrion and serving as food for many other animal species. They are also very useful as indicators of the environmental quality of the marine environment, due to their sensitivity to environmental changes, and can be used in programs to control and monitor the degree of pollution in the coasts. The present project will characterize the intertidal pools of the Collins Bay from the point of view of the composition of the community of gammarid amphipods and their relation with the environmental parameters and will obtain data of the structure, population dynamics and functional group of the most representatives species. The South Shetland Islands, because of their geographical location, represent an area sensitive to the effects of climate change and therefore the studies of their faunal communities are relevant in estimating the rate and direction of environmental and ecological changes over time. The Fildes peninsula has been categorized as Antarctic Specially Protected Area (ASPA) No. 125 (Patrimonio Natural, 2009). This category has as general objective the preservation of species and genetic diversity of representative areas of the Antarctic ecoregion (Piñeiro et al., 2012). In this sense, the contribution provided by the information on the characteristics of the communities becomes fundamental to meet those objectives.