Words by Abi Scaife
Over a century ago, giant blue-grey sei whales vanished from Argentina's Patagonian coast thanks to hunting. Today, they are making a comeback.
The sei whale, a kind of baleen whale, can grow up to 19.5 m (64 ft) in length and weigh as much as 28 t (28 long tons; 31 short tons).
The whales have been making a slow and steady return over the last eighty years, but the incredible species only breed every two to three years, so it is only recently that there have been enough of them for anyone to notice.
Bans on commercial whaling that have come through in the last 50 years have been huge in helping the species return.
"They disappeared because they were hunted, they did not become extinct but were so reduced that no one saw them," said Mariano Coscarella, biologist and researcher in marine ecosystems at the Argentine state science body CONICET, to Reuters.
Thanks to funding from National Geographic's Pristine Seas project, Mariano’s team were able to fit some of these incredible sei wales with satellite trackers.
Coscarella said that the return of the sei whales can be considered a conservational success, but warned that if the ban on whaling is reversed, so too could this progress.
This is incredible news, and such an important reminder that the work we do to protect these creatures goes a long way.
At Smiley Movement, we like to elevate the work of charities across the world. Here are three charities whose causes align with the themes in this article.
Blue Marine Foundation. A charity dedicated to restoring the ocean to health by addressing overfishing, one of the world's biggest environmental problems. Support them here.
The Ocean Conservation Trust. A charity of Ocean optimists taking action to protect and restore nature for a thriving Ocean. Find out more here.
Marine Conservation Society. This charity is fighting for a cleaner, better protected, healthier ocean: one we can all enjoy. Learn more here.