Edited by Palomares, M.L., Pruvost, P., Pitcher, T. and Pauly, D.

DIRECTOR'S FOREWORD

A map of the world with points wherever Ecopath models exist would be covered with such points, and Antarctica, which would have been an exception before, would be represented by the models in this report. In fact, there had been a model of Antarctica published earlier, by Astrid Jarre and others (Trophic flows in the benthic shelf community of the eastern Weddell Sea, Antarctica. p. 118-134. In B. Battaglia, J. Valencia and D. Walton (eds.) Antarctic Communities: Species, Structure and Survival. Cambridge University Press, Cambridge, 1995), based on work by P.H. Schalk and others, published in Trophic Models of Aquatic Ecosystems (V. Christensen and D. Pauly, eds., ICLARM Conf. Proc. 26, 1993). The various models documented here, however, will allow comparisons between subsystems and thus enable, for Antarctica, the kind of detailed comparative analysis that has long been possible for other areas.

Such comparison, having provided numerous insights for tropical and temperate systems, can be expected to do the same for Antarctic systems. Notably, it will be possible to quantify the role of pelagic-benthic coupling, assumed to play an important role in polar systems. Also, the dominance of marine mammals and birds will be amenable to comparative study, especially as Arctic systems where these homoeothermic animals dominate have also been described.

Two workshops, both sponsored by the Sea Around Us Project, funded by the Pew Charitable Trusts, led to this report: one held on 15-17 April 2003 at the Fisheries Centre, where various models were presented and their implications studied; and the other held on 29 September to 2 October 2003 at the Muséum National d'Histoire Naturelle in Paris, where a group of French researchers with experience in the Kerguelen Islands worked on refining an ecosystem model of the waters around that island. This workshop was proposed and followed by visits by Mr. Patrice Pruvost, working with Dr. M.L. Deng Palomares and others at the Fisheries Centre. This report, thus, is also a testimony to the collaboration between the Fisheries Centre and the Muséum National d'Histoire Naturelle.

We would also like to acknowledge cooperation between the Sea Around Us Project and the Renewable Resources Assessment Group (Imperial College, London, UK: Dr David Agnew) and the Falklands Islands Government (Dr John Barton) for advice and data concerning the Falklands Islands marine ecosystem and its fisheries, even if we were unable to consider all of them in the pilot models of the Falklands published in this report.

Daniel Pauly
Director, UBC Fisheries Centre

ABSTRACT

An account is presented of two workshops, at which food web (Ecopath) models of Antarctic ecosystems were constructed and/or presented. These cover 4 areas: the Antarctic Peninsula, the Kerguelen Islands, the Falkland Islands and Southern Pitcairn Island, New Zealand. For each region, a model is presented, and in two regions (Antarctic Peninsula and Falkland Islands), mechanisms are further identified which give structure to these ecosystems (competitions between krill-eating species, effect of fishery). Overall, the contributions in this report contribute to our understanding of feeding interactions in Antarctica, and hence of the likely effect of fishery in these waters.

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