The impact of environmental change on the Antarctic silverfish Pleuragramma antarcticum – Identifying physiological and ecological limits

This project aims to investigate the vulnerability of the Antarctic silverfish, Pleuragramma antarcticum, to environmental alterations due to climate change. Climate change in the marine Antarctic is reflected in increasing temperature and reduced salinity, both entailing alterations in phytoplankton and zooplankton composition (species composition and size structure of the community).

P. antarcticum (Notothenioidei, Perciformes; Fig. 1) is a herring-like pelagic fish species and occurs in loose shoals. In particular in high Antarctic shelf areas, this endemic species distinctly dominates pelagic fish communities. P. antarcticum is a key species in the Antarctic marine food web as it provides a major trophic link between zooplankton and the systems’ top predators, such as seals and penguins. Evidence suggests that this species might be highly sensitive to direct effects of climate change, i.e. increasing temperature and reduced salinity, as well as to indirect effects such as alterations in prey composition and availability.

Accordingly, this project involves experimental studies on physiological sensitivity of P. antarcticum to changing temperature and salinity regimes, as well as feeding experiments to investigate the impact of changes in prey availability, prey size, and prey energy content on survival and condition of P. antarcticum (Fig. 2). This study will provide a comprehensive picture of environmental sensitivity of this Antarctic marine key species.



Fig. 1.Shoal of Pleuragramma antarcticum caught by means of a bentho-pelagic net in the north-eastern Weddell Sea (FS “Polarstern” Expedition ANT XXI/2, 2003/2004)



Fig. 2.The project involves experimental studies on the sensitivity of P. antarcticum to direct and indirect effects of climate change

Scientists

Dr. Katja Mintenbeck
Dept. of Biosciences | Integrative Ecophysiology
Alfred-Wegener-Institute, Bremerhaven

Main collaborative partners:

Prof. Dr. Hans Otto Pörtner, Alfred Wegener Institute, Bremerhaven, Germany (hosting lab)

Prof. Dr. Wilhelm Hagen, University of Bremen, Germany

Prof. Dr. Myron Peck, Institute of Hydrobiology and Fisheries Science, University of Hamburg, Germany

Research areas

Southern Ocean: Weddell Sea and Bransfield Strait

Publications

Mintenbeck K, Jacob U, Knust R, Arntz WE, Brey T, (submitted). Relative trophic vulnerability of fish – The search for Achilles‘ heel in a high Antarctic food web. Journal of Animal Ecology.

Jacob U, Thierry A, Brose U, Arntz WE, Berg S, Brey T, Fetzer I, Jonsson T, Mintenbeck K, Möllmann C, Petchey O, Raymond B, Riede S, Williams RJ, Dunne JA, (submitted). The role of body size in complex food webs: A cold case. Advances in Ecological Research.

Mintenbeck K, 2011. The impact of environmental change on the Antarctic silverfish Pleuragramma antarcticum. Reports on Polar and Marine Research, in press.

Mintenbeck K, Damerau M, Hirse T, Knust R, Koschnick N, Matschiner M, Rath L, 2011. Biodiversity and zoogeography of demersal fish. Reports on Polar and Marine Research, in press.

Mintenbeck K, Krägefsky S, 2011. Climate depending processes in pelago-benthic coupling and food webs – Part IV: Krill and Fish. Reports on Polar and Marine Research, in press.

Rath L, Mintenbeck K, Jacob U, Möllmann C, 2011. Functional response of demersal fish to a changing environment. Reports on Polar and Marine Research, in press.

Homepage

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Research funding organisation

German Research Foundation

Project numbers: MI 1391-1
Funding period: September 2009 – September 2012