After more than a century of absence, the beautiful sei whales have returned to the waters off Argentina’s Patagonian coast. These massive blue-grey beasts were on the verge of extinction due to persistent hunting in the 1920s and 1930s. Whaling ships operating along and beyond Argentina’s shores destroyed the sei whale population, causing them to disappear from the region. However, thanks to global commercial whaling regulations enacted in recent decades, sei whales are returning to their erstwhile waters.
After nearly a century of being hunted to near extinction, sei whale populations are now bouncing back
Mariano Coscarella, a biologist and marine ecosystem researcher at Argentina’s CONICET scientific agency, explained to Reuters that they had disappeared because they were hunted. “They did not become extinct but were so reduced that no one saw them,” he said.
“After nearly a century of being hunted to near extinction, sei whale populations are now bouncing back and returning to their former habitats,” he added.
He went on to say that it took decades for sei whale numbers to recover enough for sightings to resume, and that in this case, it took more than 80 years.
According to Coscarella, these whales reproduce every two or three years, “so it nearly took 100 years for their population to reach a level where people could notice their presence.”
Sei whales are from the baleen whale family. They are distinguished by their slim, streamlined bodies that are often bluish-grey. These whales are distinguished by their long, curving dorsal fins and comparatively tiny, pointed flippers.
Sei whales can grow to lengths of 62–66 feet and weigh 28–45 metric tons. They feed on tiny fish and plankton by filtering water with their baleen plates.
The CONICET team in Argentina recently fitted some sei whales with satellite trackers to monitor their migration patterns. The project was funded by National Geographic’s Pristine Seas project. They gathered valuable footage of the whales in action via drones and underwater recordings.