The sub-Antarctic island of South Georgia, which was once a staple of the whaling industry due to the oceans surrounding the land being a vital feeding ground for whales during the summer, has seen a significant increase in whale populations since the 1986 international ban on whaling.
One of the species that was hunted to almost extinction is the massive blue whale but after 30 years of protection, large numbers of whales appear to be returning to the region. In a survey by the British Antarctic Survey (BAS), they have discovered that humpback whales are very common and blue whales number are surprisingly high.
Preliminary results revealed that 790 humpback whales were sighted during 21 days. The high density of humpback whales were seen in 2019 and 2020, indicates that over 20,000 whales now seasonally feed in these waters. A similar estimate was made for the abundant winter feeding grounds in Brazil, indicating that the waters in South Georgia and Brazil are some of the most important feeding grounds for humpbacks and are very close to full recovery after decades of the whaling ban.
Even more astonishing was the results on the endangered Antarctic blue whale. The largest animals on earth were detected acoustically and sighted once during the 2018 survey of South Georgia, but during the 2020 survey, the species was spotted 36 times with a total of 55 different animals seen. This is an unprecedented number of sightings and suggests that South Georgia remains an important summer feeding ground for this very rare species.
“After three years of surveys, we are thrilled to see so many whales visiting South Georgia to feed again,” said whale project leader Dr Jennifer Jackson, a whale ecologist with the BAS, in a statement. “This is a place where both whaling and sealing were carried out extensively. It is clear that protection from whaling has worked, with humpback whales now seen at densities similar to those a century earlier, when whaling first began at South Georgia.”
Researchers were also able to place tags on two rare southern right whales in South Georgia where their movements can be followed live here.