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This data collection project in Kerguelen and Crozet involves 7 fishing vessels and 25 trips per year with 100% observer coverage. The data collected includes latitude and longitude, depth, number of hooks, and catch for each species. The data set is checked every Monday and consists of 2.5 million data per year, with about 6,000 new data per day. The project also focuses on the abundance of whales, interactions with the fishery, photo-identification of sperm whales and killer whales, and acknowledgements to funders and partners.
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DATA COLLECTION AT SEA BY OBSERVERS KERGUELEN & CROZET N. Gasco, P. Tixier, C. Guinet
DATA COLLECTION KERGUELEN CROZET 7 fishing vessels 25 trips per year 100% observer coverage
DATA COLLECTION KERGUELEN CROZET • For each longline we collect: • Lat and long, depth, number of hooks • Catch for each species
DATA COLLECTION KERGUELEN CROZET Data set is entirely checked every monday 2 500 000 data per year About 6000 new data per day
ABUNDANCE « how many whales are around the boat?? »
ABUNDANCE « how many whales are around the boat?? » Difficult question to answer ! Asking this to an observer you might end up with no data: « I don’t know for sure so I did not fill it up! »
ABUNDANCE « how many whales are around the boat?? » divide the question into several questions: - Have you been able to observe the line for whales? (night…) - If yes where whales present or absent? - If present can you tell a minimum number, a maximum number? Or both It’s a lot easier to say « well about 10 to 15 killer whales » than a exact number
ABUNDANCE « how many whales are around the boat?? » * Has to be filled up wih one of the three cases.
INTERACTIONS Not all the groups interact: in Kerguelen we do observe Killer whales that do not interact at all. • When killer whales interact: • - they follow the boat • Birds aggregate around them to grab pieces of fish • They dive around the line
INTERACTIONS • When sperm whales interact: • - they follow the boat • They dive around the line :
Time arrival • How much time between the first hook on board and the arrival of : • Killer whales • Sperm whales Gives an idea of the average distance the boat is detected
PHOTO-IDENTIFICATION All observers are equiped with SLR camera and a 100-400mm lens:
PHOTO-IDENTIFICATION Sperm whales: as many pictures as possible
PHOTO-IDENTIFICATION Killer whales Eye patch
PHOTO-IDENTIFICATION Killer whales: 2 protocols Time available And weather conditions ok No time available Or poor conditions 30 minutes Pictures of all the individuals Update the catalogs 5 – 10 minutes Pictures of some of the individuals Identifies the groups for each line
Acknowledgements CEBC - CNRS Fundings and Partnership Terres Australes et Antarctiques Françaises Réserve Naturelle des TAAF Armements de pêche à la légine réunionais Institut Polaire Français Muséum National d’Histoire Naturelle de Paris Coordinators Dr Christophe Guinet Cédric Marteau Pr. Guy Duhamel Thierry Clot Data Collection Fishery observers and field workers of Possession Island – special thanks to Nicolas Gasco Help in analyses M. Authier, M. Viviant, C. Barbraud, D. Pardo, D. Pinaud, J. Vacquie Garcia, T. Jeaniard Dudot, P.Monestiez Photographers AUBERT Jean Luc; BARRETT-LENNARD Lance; BEILLOEIL; BELBEYC'H Bruno; BERTHET Philippe; BERTRAND Geoffrey; BLANCHARD Pierrick; BOITEAU Christophe; BONNET Joël; BOST Charles-André; BURLE Marie-Hélène; CARCAILLET Christopher; CARDOT Gilles; CHEVRIER Claude; DE STEPHANIS Renaud; DERVAUX Antoine; DESMARET Rolland; DESPIN Bernard; DONDELINGER Caroline; DOREMUS Ghislain; DUFRENE Rémy; FERNANDEZ Eric; FOURNIER Jean-Charles; GASCO Nicolas GAUTHIER-CLERC Michel; GOUEDARD Yvon; GUINET Christophe; HANDRICH Yves; HANUISE Nicolas; HOARAU Eric; LANGUENOU Roger; LE CORRE Yann; LEGRAN Jérôme; LEMARCHAN Christian; LEQUETTE Benoît; LERIDON Jean; LEROUX Eric; LESCAROUX Jean-Michel; LOUBON Maxime; MAISON Jérome; MANGIN Stéphane; MANILEVE Patrick; MARECHAL Pierre; MELLEE Jean-Luc; MOURIES Jacques; NOORKHAN Alain; NOYAN Patrick; PAULIN Rémy; PAWLOWSKI Frédéric; PERROT Yohann; PETER Jean; RIDOUX Vincent; RINGOT Frédéric; SCHWEBEL Luc; SORIN Dominique; STENBERGER Ludovic;THERON Franck; TIXIER Paul; VERLAND Henri; VERMANDE Hugues; VILLEMIN Catherine; WEIMERSKIRCH Henri