Failed To Be Led Into The Sea And Found To Be Seriously Ill, Killer Whale Trapped In The Seine Will Be 'put To Sleep'

Killer whale illustration. (Wikimedia Commons/Ronnie Robertson)

JAKARTA - A killer whale trapped in France's Seine River will be euthanized after plans to bring it back to sea failed, while scientists agree the whale is seriously ill.

The whale, 4 meters (13 ft) long and identified as a male, was first spotted at the mouth of the Seine on May 16, between the port of Le Havre and the Normandy town of Honfleur, before swimming dozens of miles upstream, reaching west of the city of Rouen.

After a meeting with national and international scientists, including marine mammal specialists, the local prefecture on Saturday tried to guide the whales back to the sea with drones while making orcas sounds.

But the whale responded "erratically" and "uncertainly" to sound stimuli, the prefecture of the Seine maritime region said in a statement. The sound recording of the whales capturing what they say is similar to the animal's distress call.

"Attempts to bring the whales back to sea have failed, and to prevent increasing stress levels, the decision was made to stop intervention at night," he said.

The scientists reviewed images and data from the intervention and concluded the animal had mucormycosis, or black fungus, a disease seen in whales in North America but not yet observed in Europe.

After infecting the animal's weakened skin, the disease can spread to the heart, lungs and brain, which explains the whale's disorienting behavior, the prefecture said. He added that the disease seemed very advanced in this case and may have caused the whales suffering.

"Under these conditions, the group of experts concluded unanimously, the only possible solution is to put the animal to sleep to end its suffering and, also, to carry out further analysis of the disease it is carrying," the prefecture added.

Experts from the French office of biodiversity (OFB) as well as the NGO Sea Shepherd were among the experts involved in the failed rescue operation.