News - June 7, 2017

Conjoined twin harbour porpoises found in North Sea

Albert Sikkema

Fishermen caught a two-headed harbour porpoise in the North Sea. A unique specimen, says marine researcher Mardik Leopold.

© Henk Tanis

A Dutch cutter has caught a harbour porpoise with two heads in the waters of the North Sea. The fishermen took pictures of the animal before throwing it back into the water. ‘We have written and published a scientific paper on this unique specimen in a very short time’, says researchers Mardik Leopold of Wageningen Marine Research, ‘because we have never before seen something similar in harbour porpoises. We also provide a list of similar cases for other cetaceans.’ He wrote the article together with first author Erwin Kompanje, assistant professor at the Erasmus MC in Rotterdam.

Unique material
The fishermen who caught the harbour porpoise in their net decided not to bring the animal on land. Ownership of a harbour porpoise is illegal, as it is an endangered species and the fishermen were wary of getting fined. Leopold: ‘That is a huge shame, of course, as unique scientific material has thus been lost, and nobody really benefits from releasing it back into the sea.’

Leopold hopes that the legislation can be changed in such a way that caught dead harbour porpoises and other sea mammals can henceforth be brought back to land for scientific research. ‘I am very interested in dead harbour porpoises that are found further off the coast: in the current situation, I have to work with dead animals that wash up on shore’, says the marine scientist.