Abstract

After the first phocine distemper virus (PDV) epidemic in Germany in 1988, it was recognized that there was little knowledge on marine mammals in German waters. Since 1989/90 the state of Schleswig-Holstein, Germany, namely the Ministry of Agriculture, Environment and Rural Areas of Schleswig-Holstein as well as the National Park Office, has financed a very well structured and successful marine mammal stranding network. Schleswig-Holstein is the only state in Germany which has both North and Baltic Sea coasts (Figure 1). Another important feature of the state is the Wadden Sea on the North Sea side with its tidal amplitude, which has been added to the UNESCO World Heritage List in June 2009. At the moment there are only three indigenous marine mammals in German waters: harbor seal (Phoca vitulina), gray seal (Halichoerus grypus), and harbor porpoise (Phocoena phocoena). Only the latter is native to the German Baltic waters. All marine mammals are reported and/or transported to the Research and Technology Center Westcoast (FTZ) in Büsum, an affiliation of the University of Kiel, Germany. National Park rangers and seal hunters are appointed to patrol the beaches and coastlines to look out for sick or dead pinnipeds or cetaceans (Figure 2). Hunting of seals has been banned in Germany in the mid seventies. The animals are still subject to the hunting law, but are ensured a year-round close season. The perennial patrol ensures applied and monitoring research aiming in understanding the development of the health of marine mammals and effects of anthropogenic activities. Combined with other investigations such as abundance estimates and acoustic assessment, impacts on individual and population level can be estimated.

At the FTZ the animals are necropsied and a number of further investigations are carried out (e.g., virology, histology, microbiology, parasitology, serology). Results of the examinations are directly relevant for political decisions and are presented at different international meetings, (ASCOBANS, ICES, IWC). The stranding network also helps fulfill national and international agreements and guidelines. Overall about 3,000 whales (1990–2010) and more than 2,000 seals (1996–2010) were examined in course of the stranding network. In the last two years alone, about 900 porpoises and seals were investigated at the FTZ.

The stranding network also includes the care-taking of orphaned pups. Especially from May to July (with a peak in mid June) the seal hunters and park rangers are called several times a day to check on a pup. If it turns out to be left alone by its mother the pup is brought to the Seal Center Friedrichskoog where it is reared (~ 80 p.a.). After 2 ½ – 3 months of rehabilitation they are released again into the Wadden Sea. The seal center is open to the public and trained staff brings awareness to the problem of orphaned pups. A third effort for a better understanding of the health situation of marine mammals in German waters are the two annual seal catches in the North Sea, where scientists of the FTZ go out to a sandbank to catch harbor seals for tagging, measuring, blood sampling, auditory tests, etc.

Figure 1. Map of Germany (left) and North and Baltic Sea coastlines of Schleswig-Holstein, Germany (right).

Figure 2. Map of Schleswig-Holstein with stations of freezers and seal hunters.

Acknowledgements

The authors would like to thank the Ministry of Environment and the Supreme Hunting Administration for financial support. They would also like to show their appreciation to the entire team of park rangers and seal hunters for their invaluable time effort and information exchange. Also many thanks go to Dr. Jörg Driver and the staff of the Seal Center Friedrichskoog. The authors wish to thank all people helping in the necropsies and seal catches.