GRD: Seen any harbour porpoises lately?

10.03.2016 17:31
Kategorie: News

Marine organisation seeks public's assistance

As in previous years, the GRD (Society for Dolphin Conservation) is appealing to the public to report any sightings of harbour porpoises (Phocoena phocoena) along the North Sea coastline and in German rivers and estuaries.

Gallery 1 here

As early as February 14th this year, the first sighting of a harbour porpoise was reported in Hetlingen, moving towards Hamburg. Sightings have also been reported in the Jade and Weser rivers.

Native to German waters, harbour porpoises (Phocoena phocoena) are the smallest cetaceans in the world. GRD biologist Denise Wenger launched a programme in 2007 in which the public are encouraged to report sightings of any harbour porpoises in the rivers along the North Sea coast. According to her, a lot of information about the animal and its characteristics can be learnt because of the many reports of sightings sent in by the public. In fact, in recognition for establishing the programme, Wenger had received the “Trophée de femmes” award, an environmental award for women presented by the Yves Rocher Foundation (details here).
The analysis of the sightings has revealed a surprising detail: After nearly a century of absence, the harbour porpoises are coming back. In the springtime, they can be seen frequently in the rivers of northern Germany, as far as Bremen and Hamburg. In 2012 and 2013, in the port of Hamburg, schools of porpoises can be seen hunting for smelts.

As the smelts travel from the North Sea to their spawning grounds in the freshwater areas of the Elbe, porpoises follow these migrating smelt as a source of food. Another prey animal that the porpoise are attracted to are the rare and legally protected twaite shad.

Early sightings of harbour porpoises in mid-February

In 2013, there were numerous sightings of porpoises in the Weser and Elbe. In January and February that year, the smelt started their annual spawning migration. In 2014 and 2015, only a few porpoises were sighted in the Elbe and Weser, much earlier than usual. It was concluded that the harbour porpoises were not at the coast so early in the year, but instead were at the wintering areas where they preyed on other fish species like herring.

This year, the smelts have shown up as early as mid-February in the south of Hamburg, much earlier than their arrival in the previous year. Now, it just remains to be seen whether and how many harbour porpoises migrate up the rivers this year, triggering a “spring season of harbour porpoises” in the Weser, Elbe and especially Hamburg again, or whether they have missed out on the arrival of smelts again.

Hence, the GRD is requesting all residents to keep a lookout and to report any signs of harbour porpoises to them by phone or WhatsApp on +49 (0)176-22208271, or online. Be sure to include the number of animals, date, time and place of the sighting.

Photos of these animals (which are often seen only briefly) are also welcome, but do keep in mind that the animals should not be chased, harassed or touched during the course of photo-taking.
In case you encounter a dead harbour porpoise, take note of the place the body was found, the size of the animal, and also any abnormalities or injuries. Photos would be very useful to enable conclusions to be drawn about the animal's cause of death.

Further Information:

Report signs of porpoises online via: