A starving beluga whale stranded in France’s river Seine for more than a week has been put down after it fell sick while being transported towards the sea in a risky rescue operation on Wednesday.
The animal was euthanised after he developed breathing difficulties and was seen to be in pain.
Officials in northern France had warned the 1,800-pound animal, a protected species that lives in cold Arctic waters, was in poor health and worryingly thin.
Some 24 divers and rope-handling rescuers worked over nearly six hours in the early hours of Wednesday morning to lift the cetacean from the river by net and crane in the hope of getting it back to the sea.
The distressed animal was shot with a vitamin infused dart at the weekend after it refused to eat frozen herring and live trout offered it by rescuers.
Twelve vets checked the 13-foot beluga after it was placed on a barge before being transferred to a refrigerated truck and driven towards the coastal town of Ouistreham.
It was still alive when it reached Ouistreham but was weak and struggling to breathe. Those involved said later on Wednesday morning that he had been euthanised due to his worsening condition.
"During the journey, the veterinarians confirmed a worsening of its state, notably its respiratory activities, and at the same time noticed the animal was in pain, not breathing enough," Florence Ollivet Courtois, a French wild animal expert, said.
"The suffering was obvious for the animal, so it was important to release its tension, and so we had to proceed to euthanize it."
Conservation group Sea Shepherd France said veterinary exams after the beluga's removal from the river showed it has no digestive activity.
The whale experienced distress after it was moved to a refrigerated truck and during the approximately 160-kilometer (99-mile) drive to the Normandy coast.
"Despite an unprecedented rescue operation for the beluga, we are sad to announce the death of the cetacean," said officials from the Calvados region.
"The decision to euthanise the beluga was taken as it was too weakened to be put back into water."
The whale was spotted more than a week ago heading towards Paris before being stranded about 81 miles inland from the Channel at Saint-Pierre-la-Garenne in Normandy.
Its progress was blocked by a lock 44 miles northwest of the capital on Friday setting up a nail-biting race against time to rescue the beluga.
The operation to return it to the sea was known to be highly risky and his death had been seen as a possibility.
"It could be that he dies now, during the handling, during the journey or at point B," said Isabelle Brasseur of the Marineland sea animal park in southern France, part of a Marineland team sent to assist with the rescue, ahead of the attempted rescue.
Interest in the beluga's fate has spread far beyond France, generating a large influx of financial donations and other aid from conservation groups as well as individuals, officials said.
While belugas migrate south in the autumn to feed as ice forms in their native Arctic waters, they rarely venture so far.
According to France's Pelagis Observatory, which specialises in sea mammals, the nearest beluga population is off the Svalbard archipelago, north of Norway, 3,000 kilometres from the Seine.
The trapped whale is only the second beluga ever sighted in France. The first was pulled out of the Loire estuary in a fisherman's net in 1948.
In April, a sick orca died of natural causes after getting separated from its pod and swimming up the Seine.