Southern fin whales have recovered to large numbers in the Antarctic

Aerial surveys have found groups of up to 150 fin whales feeding near Antarctica, a sign that populations have bounced back since since the 1976 ban on hunting these whales

By Jason Arunn Murugesu

Large groups of southern fin whales (Balaenoptera physalus quoyi) have been seen in the Antarctic for the first time since since a moratorium on commercial whaling came into force in 1986.

Fin whales are the second largest species of whale in the world, measuring 22 metres long on average and weighing 70 tonnes. Their numbers dramatically dwindled in the Antarctic in the 20th century as they were hunted for their oil.

Fin whale hunting in the southern hemisphere has been prohibited since 1976. Since then, there have been anecdotal sightings of the whales around Antarctica, but no major survey assessing their numbers.

Helena Herr at the University of Hamburg in Germany travelled to the Weddell Sea in Antarctica in 2018 on the icebreaker Polarstern.

Using a helicopter, the researchers surveyed 3251 kilometres of ocean between April 2018 and March 2019. The team counted 100 groups of fin whales, consisting of up to four whales, and eight unusually large groups of up to 150 whales feeding together.

“I really love seeing whales from the air because it’s spectacular to have them at such a close distance and to hear them,” says Herr. “I even love the splashes of water in your face – it feels like you’re among them and joining them in their feeding frenzy.”

Herr and her colleagues estimate that there are close to 8000 fin whales in the area in total.

She says the recovery of these whales is ultimately a good news story. “But we shouldn’t forget that climate change continues to be a threat and that we need to make sure that this story can continue,” she says.

Journal reference: Scientific Reports, DOI: 10.1038/s41598-022-13798-7

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