International Scholarly Research Network
ISRN Zoology
Volume 2012, Article ID 106259, 8 pages
doi:10.5402/2012/106259
Research Article
Postmortem Health and Pollution Investigations on Harbor Seals
(Phoca vitulina ) of the Islands Helgoland and Sylt
Antje Kakuschke,
1
Juergen Gandrass,
1
O. P. Luzardo,
2
L. D. Boada,
2
Annalisa Zaccaroni,
3
Simone Griesel,
1
Mechthild Grebe,
1
Daniel Pr¨ ofrock,
1
Hans-Burkhard
Erbsloeh,
1
Elizabeth Valentine-Thon,
4
Andreas Prange,
1
and Katharina Kramer
1
1
Marine Bioanalytical Chemistry, Institute of Coastal Research, Helmholtz Centre Geesthacht, 21502 Geesthacht, Germany
2
Department of Clinical Sciences and Instituto Canario de Investigaci´ on del C´ ancer, University of Las Palmas de Gran Canaria,
35080 Las Palmas de Gran Canaria, Spain
3
Department Veterinary Medical Sciences, University of Bologna, 47042 Cesenatico, Italy
4
Immunology Department, Health Diagnostics and Research Institute, South Amboy, NJ 08879, USA
Correspondence should be addressed to Antje Kakuschke, antjekakuschke@web.de
Received 19 November 2011; Accepted 20 December 2011
Academic Editors: A. Arslan, S. P. Lambeth, and C. P. Wheater
Copyright © 2012 Antje Kakuschke et al. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Helgoland and Sylt are important centers of tourism in the North Sea. Harbor and grey seals are one reason for the attraction of
these islands. However, little is known about these local seal groups. The present postmortem health and pollution study describes
a multiparameter investigation of five ill harbor seals which were shot for animal welfare reasons. Firstly, results of pathology
and blood investigations support the bad prognosis of survival made in the field. Signs of inflammation in organs, malnutrition,
a high-stress level, and reduced thyroid activity were found. Secondly, metal and organic contaminants were investigated. Metal
pollutants in blood, liver, muscle, and kidney tissue were not elevated. Lead and mercury concentrations showed a decreased level
compared to former studies. Additionally, interesting insights were found for several organic contaminants in comparison with
other studies. The Helgoland seals may be influenced by the contaminants of the Elbe plume.
1. Introduction
The ongoing and increasing use of the North Sea and its
unique Wadden Sea areas for fishing, offshore wind parks,
and as dumping site for dredged material containing various
pollutants represents the main anthropogenic threat to this
ecosystem. Besides determining contamination levels of
selected environmental compartments such as sediments
or the related water column, measuring body burdens of
marine animals remains a widely established environmental
assessment strategy [1–7]. In this context, marine mammals
such as harbor seals (Phoca vitulina) are accepted indicators,
in particular for medium and long-term ecosystem changes,
due to their long lifespan and their role as top predators
within the marine food web [8]. Correlations between
bioaccumulation of environmental contaminants in the
tissues of marine mammals and immunosuppressive effects
enhancing the animals’ vulnerability to infectious diseases or
pathogens have been described [9–11].
The tissue of seals found dead occasionally along the
Wadden Sea coast line represents an important sample
material which could be used for pathological investigations
and for estimating contaminant body burdens in monitoring
programs. However, to describe complex parameters such
as the individual health status of marine mammals, an
informative set of investigations has to be performed.
Recently, we described a study including metals, organic
contaminants, selected marker proteins as well as a number
of immunological and clinical chemistry parameters to assess
the health status of individual marine mammals based on
blood samples [12].
Within the framework of the Trilateral Monitoring and
Assessment Program (TMAP), German marine mammal
monitoring activities include aerial surveys and counting of