The cetacean had been stuck in the freshwater lock at St.-Pierre-La-Garenne, some 45 miles northwest of Paris, since August 2. Its health deteriorated after it refused food, according to wildlife protection associations monitoring the situation.
It took more than 80 rescue workers six hours to extract the animal from the lock, Reuters reported, after which it was placed on a barge, where it underwent medical checks.
However, scientists had been concerned about the animal’s “alarming” weight loss and had to euthanize it soon afterward. Its death was confirmed by officials from the Essonne Department Fire and Rescue Service in a video message.
“During the trip, the veterinarians noted a deterioration in its condition, particularly in its respiratory activity, and we were able to see that the animal was in anoxia — ie, insufficiently ventilated — so this animal was obviously suffering and we decided that it was pointless to release it and so we had to proceed with its euthanasia,” said Florence Ollivet-Courtois, veterinarian at the fire and rescue service.
Vets had earlier hoped the whale could be transported to the Normandy region and ultimately released into the sea.
According to Reuters, it weighed around 800 kilograms (1,764 pounds) but should have been about 1,200 kilograms (2,646 pounds).
The beluga’s natural habitat is in the Arctic and sub-Arctic regions. Although the best-known population is found in the St. Lawrence estuary in Quebec, Canada, the closest to the French coast is in Svalbard, an archipelago in northern Norway, some 1,900 miles from the Seine.
No one knows how the beluga lost its way, but sea ice loss in Arctic waters is opening the area up to more shipping, fishing and other human activities, affecting the whales’ ability to communicate and navigate, according to WWF. Finding food and searching for mates is becoming much more difficult for the species, as well.
In recent years, many species of marine mammals have been reported in France, far from their primary habitat. Possible reasons could include health status, age, social isolation and environmental conditions, among others, according to France’s Pelagis Observatory, which specializes in the study of sea mammals.
CNN’s Angela Dewan contributed to this story.