The south-eastern North Sea:Losses of vertebrate fauna during the past 2000 years

At least 31 species of marine mammals, marine and coastal birds, and marine and anadromous fish have disappeared temporarily or permanently from the coasts of The Netherlands and in most cases also from the south-eastern North Sea (south of 54 degrees N) during the past 2000 years-In 18-22 cases, the disappearance was probably due to overexploitation. For 9-12 species, physical destruction of their habitat was involved and, for 3-5 species, pollution probably played a part. Five species have returned to the area; these are doing very well. Three species may return through expansion of populations elsewhere. Anadromous fish and demersal fish species that have disappeared because of bottom-trawling in the North Sea have little chance of returning under the present conditions. For the gray whale (Eschrichtius robustus) and the Dalmatian pelican (Pelecanus crispus) suggestions are made to investigate the possibilities for re-introduction. (C) 2000 Elsevier Science Ltd. All rights reserved.