Grey Seal Numbers in the Wadden Sea and on Helgoland in 2010-2011

Trilateral Seal Expert Group (TSEG)

Since the beginning of the trilateral cooperation of the seal experts in 1991, grey seal numbers have grown significantly and grey seals are considered an important part of the biodiversity of the Wadden Sea. From 2006 onwards, aerial surveys of grey seals have been synchronized and coordinated trilaterally within the Wadden Sea. Despite the apparent growth in numbers in Denmark to a maximum of 57 animals counted in summer, despite the observation of pups, still no births have been documented there. The pups could have come from the German colonies Dedicated grey seals surveys are only carried out in Germany and the Netherlands. Two aerial surveys are conducted during the moult (March-April) and several aerial or boat counts are conducted during the pupping season (November-January). On Helgoland (Germany), surveys are carried out from land.

Authors:

Trilateral Seal Expert Group (TSEG):
Sophie Brasseur, IMARES, Texel, The Netherlands
Thomas Borchardt, LKN Schleswig-Holstein, Nationalparkverwaltung, Germany
Richard Czeck, Nationalparkverwaltung Niedersächsisches Wattenmeer, Niedersachsen, Germany
Lasse Fast Jensen, Fiskeri- og Søfartsmuseet, Esbjerg, Denmark
Anders Galatius, National Environmental Research Institute, Aarhus University, Denmark
Sven Ramdohr, LAVES Cuxhaven, Niedersachsen, Germany
Ursula Siebert, FTZ-Büsum der Universität Kiel, Schleswig-Holstein, Germany
Jonas Teilmann, National Environmental Research Institute, Aarhus University, Denmark