Normally, harbour porpoises, seals or marine birds show on the footage of our digital aerial surveys. After basking shark and ocean sunfish our colleagues were pleased to find further exciting recordings of not quite so common species: white-beaked dolphin (Lagenorhynchus albirostris) and common minke whale (Balaenoptera acutorostrata).
The white-beaked dolphin is endemic to the North Atlantic Ocean and the North Sea with a few sightings in the western part of the Baltic Sea. The geographic range stretches between Massachusetts in the USA and France in the south and up to the Arctic ice pack between Southern Greenland and Svalbard in the north. After harbour porpoises, white-beaked dolphins are the second most common cetacean species in the North but can unlike these usually be found in open waters. In the North Sea they are often observed in the Dogger Bank area. In a comprehensive survey of all dolphin species in the European Atlantic Ocean as well as North and Baltic Sea about 10,000 individuals were counted in 2005.
Even at birth these dolphins, which can live as long as 37 years, are more than one metre long. Adult males measure just more than three metres. Characteristic are the name-giving white beak and the light grey “saddle” behind the dorsal fin as can be seen in the animals in the picture.
Despite their smaller size common minke whales are counted among the great whales. They are a relatively common species of baleen whales. In the Northern Hemisphere they are widely distributed in the North Atlantic and the North Pacific Ocean. While these animals prefer warmer waters in winter, they partly migrate up the the Arctic ice pack in summer. Some whale populations even stay in the same area all year round. Common minke whales usually live solitary or can be observed in pairs or smaller groups. They mainly feed on schooling fish (herring, capelin) and crustaceans. In the North Sea sandeels are an important source of food for the whales.
Fully grown common minke whales are about ten metres long and weigh more than nine tonnes. They reach an age of up to 50 years. Like the white-beaked dolphin, the common minke whale mainly occurs offshore in the North Sea and can occasionally be observed especially in the Dogger Bank area. The white band on the upper side of each flipper, clearly visible in the picture, is typical for common minke whales.