Rescuers are planning how to retrieve a beluga whale from the Seine.
The arctic mammal was trapped between a series of locks in a stretch of water source between Paris and Rouen.
Efforts are still ongoing to try to capture the predatory whale, but so far they have failed.
The marine conservation group Sea Shepherd France said on Monday that “feeding efforts are continuing in parallel with finding a way to get it out of the nest in the best condition”.
Over the weekend, beluga was given a “vitamin cocktail” in an attempt to maintain its nutrition.
“It’s really extremely thin. Its bones stick out. I don’t know if it’s too late,” Lamya Essemlali, president of Sea Shepherd France, told a news conference this weekend.
Attempts to feed the animal – with both dead and live salmon – were fruitless.
Beluga was first discovered in the river, thousands of miles from its homeland, last week.
It is now tens of miles away from the sea and its normal saline environment.
Experts have warned the whale not to stay too long in the warm, stagnant waters between the two locks where it currently resides.
“The beluga still won’t eat and continues to be curious,” Sea Shepherd France tweeted. Overnight, the whale “rubbed itself against the wall of the padlock and removed the plaque on its back. Antibiotics may also help.”