For the first time in decades, blue whales have been spotted off the coast of South Georgia, an island in the South Atlantic Ocean. And not just a few of them either.
Researchers near the island have found an estimated 58 whales in the waters. And while that may not seem like an immense amount, it's a miracle given the whale's troubled history off of South Georgia—a place where only one blue whale was recorded between 1998 and 2018.
It's also a sign that the mighty mammal is finally reclaiming its natural range.
A blue history
Through the 1800s and into the 1900s, whaling—the hunting of whales for their body parts—was a big business in every way.
Big ships with big crews hunted big animals in big numbers for big money.
South Georgia was a big hub for the whaling industry, hunting the whales that gathered in its deep, chilly waters to feast on krill. But by the mid-1900s, all of that whaling had taken a terrible toll on the whales there. This was particularly true of the largest animal ever to live on Earth, the blue whale.
Blue whales went from numbering in the hundreds of thousands to only a few hundred. By the time that whaling was banned in 1960s, the blues were critically endangered and just hanging on. And in the waters around South Georgia—a place where blues once numbered in the many thousands—the animal essentially disappeared.
Cautiously bright future
Since the international whaling bans, many whale species have slowly recovered their numbers. Globally, there are around 5,000 blue whales, though the numbers are under investigation. But despite recovering, the whales were still absent from South Georgia. Why?
Researchers believe that the whales experienced something called 'cultural memory loss'. Whale mothers are the ones that lead their young to feeding grounds year after year, reminding them of the places where they can expect to find food. But so many whales were killed around South Georgia during the 1900s, that there were no adults left who remembered the abundance of krill in these waters.
"There was a cultural memory, maybe, of animals that used to come to South Georgia that was lost because they were wiped out," marine researcher Susannah Calderan told Live Science.
This may be why no blues were coming back to South Georgia, even though overall the species numbers were slowly bouncing back globally. But now that they have returned, people like Calderan are hopeful that it is a sign that blue whales are reclaiming this part of the world as their own.
"This was an area that was particularly hard hit by whaling," she said, "and it is really encouraging that we're starting to see whales there again."