28. AGASSIZ TRAWL (AGT) DEPLOYMENTS

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1 28. AGASSIZ TRAWL (AGT) DEPLOYMENTS Dorte Janussen 1, Simone Brandao 2, Tomas 3 4 Havermans 5, Katharina Jörger 7, Anna Meyer-Löbbecke 8, Sarah Schnurr 7, Martina Vortkamp 2, Laura Würzberg 8 Zinnkann 8, and Angelika Brandt DZMB 3 UA 4 UGent 5 IRSNB ZSM 7 8 ZMH. Objectives in order to sample a representative collection of animals for zoogeographical, of our results, as far as possible we conducted the employments according to as possible, the AGT and other benthic gears were employed within the same Work at sea we used the new AWI-AGT, which is symmetrical and can be deployed also upsidedown, which is not an advantage though, because only one of the net surfaces is equipped for sliding over the ground and sampling. Because the symmetrical AGT proved to be unstable and would easily turn around during deployment, after side, but for that reason has proven to be much more stable than the new trawl. As the function of the new and old trawl is identical, we here use the term AGT for both. After the second failure, deployment no. 5, we made some improvements in order to keep the net on the bottom, such as fastening a steel chain to the especially the smaller animals. Preliminary and expected results 115

2 ANT-XXVIII/3 o S, 10 o megafauna of mainly holothurians, ophiuorids, molluscs, polychaetes and also a few sessile cnidarians. o S, 12 o o S, 39 o provided lots of big stones and many animals. The megafauna was abundant meshed inner net, is designed to mainly the bigger animals, less smaller ones. o o was well represented, e.g. by crustaceans. Tab. 28.1: Station PS Date Deployment Lat. Lon. Depth, [m] Trawl. dist., calc., [m] Catch/ remarks 79/ AGT 1/ new 52 o 9 o AGT 2 52 o 10 o AGT 3 52 o S 8 o W AGT 4 51 o 12 o Diverse megafauna AGT 5 51 o 12 o / o 12 o Good 79/ AGT 7 51 o 12 o Good 79/ AGT 8 51 o 39 o Stones, good 79/ AGT9/old 51 o 39 o 1891 Stones, good 79/ AGT 10/ old 53 o 52 o 330 Animals, best

3 28. Agassiz trawl (AGT) deployments Fig. 28.1: The old AWI-AGT and the Rauschert Dredge used, the latter belongs to Charlotte Havermann (photo Ann Christine Zinnkann) Data management Refer to page

4 The Expedition of the Research Vessel "Polarstern" to the Antarctic in 2012 (ANT-XXVIII/3) Edited by Dieter Wolf-Gladrow with contributions of the participants Alfred-Wegener-Institut Helmholtz-Zentrum für Polarund Meeresforschung D BREMERHAVEN Bundesrepublik Deutschland ISSN

5 Hinweis Die Berichte zur Polar- und Meeresforschung werden vom Alfred-Wegener-Institut Helmholtz- Zentrum für Polar- und Meeresforschung in Bremerhaven* in unregelmäßiger Abfolge herausgegeben. Notice The Reports on Polar and Marine Research are issued by the Alfred-Wegener-Institut Helmholtz- Zentrum für Polar- und Meeresforschung in Bremerhaven*, Federal Republic of Germany. They are published in irregular intervals. Sie enthalten Beschreibungen und Ergebnisse der vom Institut (AWI) oder mit seiner Unterstützung durchgeführten Forschungsarbeiten in den Polargebieten und in den Meeren. Es werden veröffentlicht: Expeditionsberichte (inkl. Stationslisten und Routenkarten) Expeditions- und Forschungsergebnisse (inkl. Dissertationen) wissenschaftliche Berichte der Forschungsstationen des AWI Berichte wissenschaftlicher Tagungen They contain descriptions and results of investigations in polar regions and in the seas either conducted by the Institute (AWI) or with its support. The following items are published: expedition reports (incl. station lists and route maps) expedition and research results (incl. Ph.D. theses) scientific reports of research stations operated by the AWI reports on scientific meetings Die Beiträge geben nicht notwendigerweise die Auffassung des Instituts wieder. The papers contained in the Reports do not necessarily reflect the opinion of the Institute. The Berichte zur Polar- und Meeresforschung continue the former Berichte zur Polarforschung * Anschrift / Address Alfred-Wegener-Institut Helmholtz-Zentrum für Polarund Meeresforschung D Bremerhaven Germany Editor: Dr. Horst Bornemann Assistant editor: Birgit Chiaventone Die "Berichte zur Polar- und Meeresforschung" (ISSN ) werden ab 2008 als Open-Access-Publikation herausgegeben (URL: Since 2008 the "Reports on Polar and Marine Research" (ISSN ) are available as open-access publications (URL: