Benthic trophic networks of the southern North Sea

Author(s)
Jan Steger, Hendrik Pehlke, Benoit Lebreton, Thomas Brey, Jennifer Dannheim
Abstract

We examined whether taxonomically distinct benthic communities from contrasting sediments in the German Bight (southern North Sea) also differ in their trophic structure. As a case study, we compared the Amphiura filiformis community (AFC) of silty sands and the Bathyporeia− Tellina community (BTC) of fine sands using a combination of stable isotope analysis and data on trophic interactions. Differences between the food webs were evident in the feeding guild composition of important primary consumers: deposit and interface feeders are the most diverse primary consumer guilds in the AFC, whereas suspension and interface feeders play a major role in the BTC, reflecting differences in physical properties and food availability at the sediment−water interface. While all primary consumer guilds had the same trophic level (TL) in the AFC, deposit feeders of the BTC occupied a trophic position intermediate between other primary and higher-order consumer guilds, likely explained by partially incomplete knowledge of their trophic ecology and selective feeding, including the ingestion of meiofauna. Most food web properties, however, were similar between the AFC and BTC: they mainly depend on pelagic primary production, reach TL 4 and are characterized by a prevalence of generalist higher-order consumers. Furthermore, both trophic networks had similar linkage densities and high directed connectance, the latter feature suggesting considerable food web robustness. Our findings suggest that although communities in the German Bight differ in some aspects of their trophic structure, they share a similar food web topology, indicating a comparable degree of resilience towards natural and anthropogenic disturbances.

Organisation(s)
Department of Palaeontology
External organisation(s)
Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Helmholtz Institute for Functional Marine Biodiversity, Carl von Ossietzky Universität Oldenburg, Université de La Rochelle
Journal
Marine Ecology Progress Series
Volume
628
Pages
17-36
No. of pages
20
ISSN
0171-8630
DOI
https://doi.org/10.3354/meps13069
Publication date
10-2019
Peer reviewed
Yes
Austrian Fields of Science 2012
106021 Marine biology, 106026 Ecosystem research
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Aquatic Science, Ecology
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucrisportal.univie.ac.at/en/publications/ea0a6184-2b85-426c-8127-1fbf88b3e07f