European Ocean Biodiversity Information System

[ report an error in this record ]basket (0): add | show Print this page

Seals in motion. How movements drive population development of harbour seals and grey seals in the North Sea
Brasseur, S.M.J.M. (2017). Seals in motion. How movements drive population development of harbour seals and grey seals in the North Sea. PhD Thesis. Wageningen University: Wageningen. ISBN 978-94-6343-612-0. 176 pp. https://hdl.handle.net/10.18174/418009

Thesis info:

Available in  Author 
    Vlaams Instituut voor de Zee: Open access 308463 [ download pdf ]
Document type: Dissertation

Keyword
    Marine
Author keywords
    Seals - Phoca vitulina - Halichoerus grypus - Pinnipedia - Population Biology - Animal Ecology - Wadden Sea - Netherlands

Author  Top 
  • Brasseur, S.M.J.M.

Abstract
    The harbour seal Phoca vitulina and the grey seal Halichoerus grypus have been inhabitants of the Wadden Sea since millennia. Prehistoric findings indicate the presence of both species around 5000 BC. This changed dramatically in the mid Middle-Ages as around 1500 AC, the grey seal disappeared from the Wadden Sea as a consequence of persecution. With growing hunting pressure, especially in the 20th century and concurrent habitat destruction and pollution, the harbour seals reached all time low numbers in the 1970’s. Banning the hunt in countries around the southern North Sea, limiting pollution and protection from disturbance allowed the harbour seals to slowly recover and the grey seals to return to the Wadden Sea. In this thesis the population trends and inherent dynamics of the recovery for both species is described. Also the movements of individual animals are studied to explain possible mechanisms.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Author