The aquatic mammal, an unusual sight for residents of the city, was seen swimming and jumping in the water on Sunday and Monday, DR reports.

The species, a short-beaked common dolphin, is rarely seen in the area and no sightings have previously been recorded in the Limfjorden, according to researcher Carl Kinze of spotters’ website hvaler.dk.

“This is a species normally found further south than in Danish waters,” Kinze told DR.

Study of pictures of the Limfjorden dolphin confirmed that the sub-species of the animal, after it was initially thought to be a bottlenose dolphin, Kinze said.

“Firstly, we can see there’s a clearly defined bill. And you can also see the markings on the dolphin. It has four colours in principle: a black back, a yellow patch on the front, white underneath and grey on its rear. They are quite distinctive markings,” he told DR.

Several other species of dolphin are also more commonly found in Denmark, the expert added. These include the white-beaked dolphin. Both the bottlenose and common dolphins are rare, he said.

Sightings of the latter two species in Denmark – according to Kinze only around ten every year – could become more common, according to the researcher.

“We have seen them more often in Denmark the last few decades and increasingly in the current decade. That might be a fluctuation, but it could also be due to climate change,” he told DR.

“They are here now, and my gut feeling is that there will be more to come. But we will naturally need to document this,” he added.

Dolphin sightings in Denmark can be registered on the hvaler.dk website.

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