MJ. (Marjan) Addink

Research interests

Naturalis has been recording strandings of cetaceans (whales and dolphins) for nearly a century now. Most records can be viewed via the website www.walvisstrandingen.nl. The most important species that is found stranded on the Dutch beaches is the harbour porpoise Phocoena phocoena (in Dutch “bruinvis”), followed by the white-beaked dolphin Lagenorhynchus albirostris (in Dutch “witsnuitdolfijn”).

As a guest researcher within the Marine Zoology department I have been working on various aspects of cetaceans from the southern North Sea and have occasionally taken part in field work in the Atlantic Ocean and in the Red Sea and adjacent waters.

1) The study of the harbour porpoise from the southern North Sea. Using samples of porpoises taken during dissections by veterinarians of stranded and by-caught porpoises, I study the life-history of this species. I am also interested in the possible influence of pollutants on reproduction. Using old records, patterns in strandings over the past century have been studied. That has provided an insight into the temporal changes in numbers of strandings and into other aspects of the species’ biology in Dutch waters.

2) Since the middle of the 20^th century, the white-beaked dolphin is found stranded nearly every year (with yearly variations between 0-10 animals). I am interested in the changes in distribution patterns and the life-history of this species, as well as in that of a related species, the white sided dolphin Lagenorhychus (Leucopleurus) acutus (in Dutch “witflankdolfijn”), though the latter is rarely stranded on the Dutch coast.

3) The cetacean fauna of the Red Sea is relatively unknown. I have been on a few expeditions to this area. The records taken by myself and several colleagues have now been pooled with data collected by observers from Germany, Italy and Israel, and we are working on an annotated checklist that will include historical data.