Antarctic Whales Rebound to Pre-Whaling Numbers

Whales are returning to Antarctic waters in numbers not seen since before commercial whaling devastated their populations nearly a century ago.

Researchers surveying the South Orkney Islands this February recorded multiple groups of more than 100 humpback whales feeding together in a single day. The scenes matched descriptions written by the first polar explorers over a century ago, when the Southern Ocean teemed with marine life.

Since commercial whaling ended in 1986, after more than 2 million whales were killed in the Southern Ocean, populations have been slowly recovering. Humpbacks have bounced back faster than anyone expected, while blue whales are taking longer to rebuild their numbers.

"It is incredible that every day with decent weather, we could more or less guarantee seeing a group of 100-plus whales," said Dr. Matt Savoca of Stanford University's Hopkins Marine Station. "The fact that groups this size are common here is what's most remarkable."

But the recovery faces a new challenge. Industrial krill trawlers now fish the same waters where whales feed, removing the tiny crustaceans that form the base of the Antarctic food web.

The Ripple Effect

The impact goes beyond simple competition for food. When whales eat krill, they return nutrients to the water through their waste, feeding the phytoplankton that krill populations need to survive.

Industrial trawlers process krill into dietary supplements, pet food, and aquaculture feed, pulling those nutrients out of the ocean entirely. The vessels can weigh up to 3,300 tons, making them roughly 100 times larger than a humpback whale.

"When a whale eats krill, it poops out krill," said whale researcher Ted Cheeseman, who co-founded Happy Whale. "There's a nutrient recycling happening."

Political deadlock has prevented action at the international level. In both 2024 and 2025, China and Russia blocked conservation measures at the Commission for the Conservation of Antarctic Marine Living Resources.

So scientists are proposing a practical alternative: a voluntary 19-mile buffer zone around the South Orkney Islands where krill fishing would be banned. The krill fishing industry has already accepted similar buffers around penguin colonies, giving researchers hope they might support this one too.

"There is an incredible opportunity for conservation through collaboration," said Savoca. "The NGOs, scientists, and the fishing industry can come together and succeed where international agreements have failed."

The whales have survived commercial hunting and made an extraordinary comeback, proving nature can heal when given the chance.