Hobby angler Bernd Zimmermann could hardly believe his eyes when a large marine mammal appeared next to his small boat on Monday. "I like to fish far out and was close to the traffic separation scheme north of Rügen when I heard the whale blowing. It surfaced next to my boat and stayed with me for about 20 minutes," says the man from Lübeck, still moved by this rare encounter. "At one point, I saw the blow very close and knew that the rest of the animal was directly under my boat - it took my breath away for a moment!"
Finally, the whale swam off in the direction of Bornholm, "an almost mystical sight on the glassy sea," Zimmermann enthuses. He actually wanted to film this unique encounter in its entirety, "but I forgot to start the recording out of excitement!" he explains. He only managed a few quick shots. This rare event in the Baltic Sea is causing quite a stir, as humpback whales normally live in the oceans and rarely visit the shallower waters of the Baltic Sea.
A cub on the wrong track
"I can't tell the size of the animal from the pictures. What I have seen, however, is that it is a very young whale. You can also tell by the shape of the head and the distance from the head to the flipper," explains Prof Dr Judith Denkinger, Curator of Marine Mammals at the German Oceanographic Museum in Stralsund. She confirms that the young animal is a humpback whale. She can rule out the suspicion that it could be the same young whale that got caught in a fishing net in Poland in February due to a sad circumstance: that whale stranded near Denmark and was dissected. "Unfortunately, the Baltic Sea is something of a death trap for large whales."
Humpback whales are not native to the Baltic Sea. They only stray into these waters from time to time, probably when they lose their bearings on their migrations. These marine mammals, which can be up to 15 metres long and weigh up to 30 tonnes, normally live in the open oceans. According to the WWF, there are over 65,000 humpback whales worldwide, with populations in the North Atlantic, North Pacific and Southern Hemisphere. The reasons for the appearance of whales in the Baltic Sea are not always clear. It is often due to the search for food when schools of fish deviate from their usual routes due to storms. The young animal sighted near Hiddensee may also have accidentally entered the Baltic Sea during its migration from warmer regions, such as the Azores or the Caribbean, to the Arctic.
Whale sightings in the Baltic Sea on the increase
The sighting off Hiddensee is not the only notable whale sighting in the Baltic Sea in recent times. In 2016, a young humpback whale spent several months in the Greifswald Bodden and even collided with a sailing yacht. In April 2024, a large marine mammal strayed into Kiel and Glückstadt. A humpback whale was also filmed in Øresund, the strait between Denmark and Sweden, on 8 September 2024. Jens Peder Jeppesen, Director of the Øresund Aquarium and marine biologist, emphasised the special nature of this waterway: "The Øresund never ceases to amaze us and we cannot emphasise often enough how unique this passage between Sweden and Denmark is." Two humpback whales also caused a stir in the Flensburg Fjord on Friday, 8 September 2024. They even landed in Glücksburg's sports harbour, where sailing instructor Jan Philip Leon from the Hanseatic Yacht School Glücksburg filmed the impressive scene. Experts suspect that it was a young animal with its mother, with the larger animal being over ten metres long.
Don't be afraid of whale encounters!
According to Judith Denkinger, there is no need to worry when recreational boaters encounter humpback whales: "Although the animals are large, they are very gentle, so there is really no need to be afraid." She advises drivers to adapt their behaviour to the noise-sensitive animals by switching off the engine and slowing down the boat. It is important not to circle the rare guests or follow them constantly. Calm behaviour and avoiding loud noises help to avoid disturbing the majestic marine mammals - and create the ideal backdrop for Denkinger's tip: "Just enjoy the sighting!"
In case of sighting: please report
Jens Peder Jeppesen from Øresund Aquarium is calling on people to report sightings and share their experiences. The German Oceanographic Museum asks for reportswhenever skippers encounter marine mammals - including smaller harbour porpoises or seals - and to take as many photos as possible. Both can provide valuable data for researchers and improve our understanding of the movements of marine animals. If you want to know where harbour porpoises, bottlenose dolphins and the like prefer to hang out, you can take a look at the Sighting map of the Oceanographic Museum.
