Test and implementation of specific management measures to create a seal exclusion zone in the swimming area on Helgoland

Project description

The population of the native grey seals (Halichoerus grypus) developed well after their protection and subsequent recolonisation of the Wadden Sea. The positive trend of the population poses a challenge from the management perspective. There is an increasing requirement of suitable habitat, which is commonly associated with enhanced conflict potential. A special kind of conflict exists on the Heligoland Dune, where the largest grey seal colony occurs in German waters. Individual animals habituated to human presence due to spatial density and the continuous close contact between humans and animals and therefore do not display the expected escape reflex anymore. This involves an increased risk potential for swimmers, especially in the water. This study aims to test specific management measures in order to create a swimming area safe for people and to implement them officially if successful. On that account, an acoustic method shall be tested, which has not been used for that purpose yet and is based on the so called startle reflex. In contrast to conventional acoustic devices scaring off seals unspecifically, a very specific signal will be used, which has got no extensive negative effects on target and also non-target species in theory. The study investigates if the application of this system has got the desired efficiency and causes no evident negative effects in this special context.