France's largest aquarium is facing legal action over the deaths of 30 hammerhead sharks.
The NGO Sea Shepherd filed a lawsuit on Monday against Nausicaa National Sea Center, situated in Boulogne-sur-Mer near Calais, for "serious abuse and non-compliance with regulations concerning the care of wild animals in captivity".
Nausicaa caught its first sharks from the wild in Australia in 2011, all of which died over an eight-year period, with the final one passing away last Thursday.
An endangered species, the aquarium said the hammerheads died from a fungus, but Sea Shepherd claims some of them ate each other.
This does happen in the wild, Lamya Essemlali, President of Sea Shepherd France, told Euronews, but outside captivity, they have ways to escape attacks and are less aggressive because they have more space.
"Hammerhead sharks are an extremely fragile species and don't do well in captivity," she said. "They are highly migratory sharks that need large spaces."
"The law states that captivity facilities must prevent animals becoming victims of each other and obviously Nausicaa didn't do that," she added.
The aquarium invested €3 million in the project, largely from public funds, according to Sea Shepherd.
"We really regret that this money was not invested in anti-poaching efforts," said Essemlali, which is the main threat to the sharks in the wild.
"Of 30 hammerhead sharks taken from their natural habitat by the aquarium none survived: A 100% mortality rate! Shameful!" animal rights NGO 30 Million Friends wrote on Twitter.
Nicolas Ziani, Researcher from Phocean Shark Research Group told Euronews the aquarium made a "big error (in displaying) a weak, vulnerable shark species at the aquarium."
"They are a highly migratory species so are not suited for aquarium life," he added.
Euronews contacted Nausicaa and they said: "We have no comment to make on this topic. We do not comment on potential legal proceedings."
Essemlali's message was clear: "If you want to know sharks, watch great documentaries about them or go in the wild and meet them in a respectful manner, don't lock them up in an aquarium."