Aerial surveys of grey seals in the Wadden Sea in the season of 2010-2011 Continued growth, through birth and immigration

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). In Helgoland (Germany), surveys are carried out from land.