Pilot Project 2013-2015

Lobster release at the offshore wind farm Riffgat, German Bight (North Sea)

The European lobster (Homarus gammarus) population around the island of Helgoland (German Bight, North Sea) has been stagnating on a very low level for many decades. The lobster is important in a healthy marine environment. As top regulator, the lobster stabilizes the hard-bottom community and ensures a high species diversity. A mark-recapture study of hatchery-reared juvenile lobsters at the rocky island of Helgoland has shown that released lobsters are strong fidelity to their release sites. The present pilot project aims to test an offshore wind farm as a suitable habitat for lobsters. A successful settlement of lobsters at the underwater structures (natural stones) of wind farms would clearly contribute to ensure the persistence of this endangered species along the German coast. In summer 2014, few thousand hatchery-reared and marked juvenile individuals of the Helgoland lobster stock had been released at the wind turbine foundations and their scour protections of the wind farm Riffgat. Subjects of investigation predominantly concern a) the density of released individuals necessary for a successful settlement at offshore structures and b) the development of the native mobile demersal megafauna at the locations, where the lobsters were released. The effect of lobster settlement and the abundance of megafauna are investigated with dive transects and pot fishery.

This project is financed by the Lower Saxony Water Management, Coastal Defence and Nature Conservation Agency.

Team

Prof. Dr. Heinz-Dieter Franke

Dr. Isabel Schmalenbach

Michael Janke

 

Project partner

Dr. Roland Krone

 

Links

Photos and videos lobster on Helgoland

Fig. 1: Hatchery-reared juvenile lobster (Photo: I. Schmalenbach)
Pot fishery in the offshore wind farm Riffgat (Photo: M. Janke)