Changing fish habitats: trends in the development of benthic infauna

Lead Institute SF Institute of Sea Fisheries

Der Schlangenstern Acrocnida brachiata / The brittle star Acrocnida brachiata

Provision and evaluation of the temporal variability of benthos data and their interactions with bottom fish species of the North Sea

Benthic fish habitats are subject to change - due to climate impacts as well as fisheries activities. This project aims at documenting the availability of benthic infauna for demersal fishes, investigating the relationship of the variability in infauna biomass and species composition to changes ingroundfish communities.

Background and Objective

This project aims at investigating longterm changes in North Sea groundfish habitats.

Analyses focus in particular on the availability of benthic infauna as food source for demersal fishes. Distinct types of habitats in the southern and northern North Sea will be compared, where different environmental impacts can be expected.

By describing the temporal variability in the composition of the infauna, the results are intended provide necessary information to link trends in the development of benthic habitats to shifts in the fish fauna.

Approach

Samples of benthic infauna, obtained with a van Veen grab on the ‘German Small-scale Bottom Trawl Survey’ (GSBTS), will be analysed microscopically in order to derive qualitative and quantitative information on community changes. Trends in the development of invertebrate communities over the last 20 years will be statistically compared to changes in groundfish assemblages.