After an unsuccessful rescue attempt, French authorities have decided to euthanize an orca whale that got lost in the Seine two weeks ago.

The killer whale was first sighted in the Seine on May 16.

To the surprise of passers-by, he appeared between the northern French cities of Le Havre and Rouen.

At the weekend, a group of experts tried to guide the marine mammal out into the open sea with the help of sonar technology.

As the prefecture announced, tumors and rashes can be seen on aerial photographs of the animal.

The orca is suffering from an advanced fungal infestation that can cause great suffering to the animal.

In addition, other weakened mammals could become infected.

The orca's disease could also affect the brain.

This could explain his disorientation.

On Saturday, a team consisting of scientists, police and fire brigade, among others, set out to try to guide the lost orca towards the sea with the help of whale noises.

The experimental rescue attempt also used a drone that took pictures of the infected animal.

Wal was already weakened before the rescue operation

According to the Marine Mammal Research Group (GEEC), the whale was first sighted in early April by the crew of a trawler about 30 kilometers off the Normandy coast.

The video recordings are clear.

There is no doubt that it is an orca.

Since then it has been repeatedly spotted along the coast, in the Seine estuary and around 60 kilometers upstream in the Seine near Yainville.

Orcas are more commonly found off the coasts of Scotland, Iceland and Norway, and further south in the Atlantic Ocean in the Bay of Biscay, a GEEC expert explained.

But instead of moving towards the sea, the orca kept swimming back and forth, the prefecture said.

Even before the rescue operation, his condition was classified as extremely weak and the chances of survival as low.

Because the animal was already so weak, the authorities, after consulting experts, decided to use the extraordinary noise method.

This avoids using a ship at close range, which could further increase the stress level of the animal.

The whale sounds were played underwater with a loudspeaker during the mission.

The research teams then watched from boats some distance away as the orca responded to the sounds.

But instead of being guided by the sounds, the animal swam back and forth between the banks.

In order not to cause even more stress to the animal, the experiment was stopped early on Sunday evening.

Why the animal appeared in the Seine is unclear.

It has been speculated that the whale first strayed into the English Channel because it is ill and can feed more easily in the calmer waters there.