“She looks like she’s in good shape”: what is this humpback whale that’s swimming around in the Seine and “swimming pretty fast” ?

A humpback whale has been swimming in the Seine for several days in mid-October 2024 (illustrative photo). Iri_may – ENVATO ELEMENTS

A humpback whale has been swimming in the Seine for several days in mid-October 2024. The prefecture is calling for caution and asking sailors to “not attempt to approach the animal”.

It had been in the Seine estuary for several days. "A large cetacean, which appears to be a humpback whale" was observed this Wednesday, October 16, 2024, the Seine-Maritime prefecture indicated in a press release, reported in particular by France info.

The animal "swims normally, even quite quickly, and does not show any incapacity", details the prefecture.

The press release states that it is “a protected animal species, which can regularly be observed off our coasts but whose presence is relatively rare locally”.

30 tonnes approximately

The adult humpback whale measures between 11.5 and 15 metres and weighs between 25 and 30 tonnes according to the International Whaling Commission. Present in all oceans, it is one of the most observed and best studied whale species. The species is known for its “active surface behavior. It can jump out of the water and slap the water surface with its pectoral fins or tail and sometimes show curiosity toward tour boats”, the specialized site emphasizes.

Call for caution

A surveillance system has been set up. The Rouen port authority has "issued a navigation notice calling for caution and to report any presence of the marine mammal and its location", notes the prefecture.

"Do not approach the animal"

The members of the working group on marine mammals in distress set up by the Ministry of Ecological Transition have also been asked "to support the management of this unusual presence and to take appropriate measures, if necessary".

"It is definitely a humpback whale. She seems to be in good shape, so since the reports, we have been following her remotely, at the Seine estuary with correspondents from the national stranding network”, explains marine biologist Eléonore Meheust to Actu.

The prefecture asks anyone who might cross the path of the cetacean to "not try to approach the animal".