A killer whale stranded in the River Seine in France has died of natural causes, the campaign group Sea Shepherd said on Monday, after attempts to guide it back to sea failed.
"We found him late this morning," Lamya Essemlali, head of Sea Shepherd France, told Reuters.
During an attempt on Saturday to lure the whale back out to sea with a drone emitting orca sounds, the animal behaved incoherently and emitted distress calls, local officials said.
By Monday, it resembled nothing more than "a ghost of an orca", Ms Essemlali said, and it died before any attempt at euthanization could be made.
The whale's body will be moved to the shore of the river and an autopsy will be conducted, local officials said in a statement.
The orca was first spotted at the mouth of the Seine on 16 May between the port of Le Havre and the town of Honfleur in Normandy, before it swam miles upstream west of the city of Rouen.
Plans were announced on Sunday by French authorities for the whale to be euthanised after a plan to guide it back to sea failed and scientists concluded it was in agonising pain and terminally ill, the local prefecture said on Sunday.
The whale responded “erratically” and “incoherently” to a rescue mission on Saturday highlighting that the whale was in distress.
"The attempt to bring back the whale to sea having failed, and to prevent adding to it stress levels, a decision was made to stop the intervention in the evening," marine mammal specialists overseeing the mission said.