The killer whale sits atop a concrete platform at a Canary Island aquarium, belly squashed and head slowly bobbing for three minutes of grainy footage.

The Dolphin Project, the nonprofit animal-advocacy organization that released the video, says the whale — a captive female orca named Morgan — slid out of the water after a performance at Spain’s Loro Parque aquarium. There, the group says, she remained for 10 minutes.

“One would never see this bizarre behavior in nature,” said Richard O’Barry, Dolphin Project founder and an animal activist who once trained dolphins for the TV show “Flipper,” in a statement. The Dolphin Project writes it couldn’t explain why Morgan left the water but called the scene “unsettling.”

Depending upon who reviews the film, the footage shows unnatural activity or, possibly, a cetacean suicide attempt. Or it is simply normal orca behavior, as Loro Parque described it in a statement. (One orca expert contacted by The Washington Post declined to comment, arguing that devoid of context it is not possible to infer the animal’s intention.)

“It is absolutely illogical and absurd to assume that the length and the quality of such video would be sufficient to make a conclusion and declaration of such nature,” the aquarium wrote. “A voluntary stranding is a natural behavior of orcas living in the wild. For example, in the region of Valdes, Argentina, there is a group of orcas that has learned to hunt the cubs of sea lions in the shallow waters near the shore.”

In general, when whales strand themselves — especially en masse —  it is a phenomenon without scientific consensus. “There are lots of reasons for group strandings, but no agreements,” Oregon State University marine biologist Scott Baker told Livescience in 2010. Rob Deaville, manager of the Cetacean Strandings Investigation Program in the United Kingdom, told New Scientist in a January interview that they may come ashore after becoming disoriented by marine noise or pollution; for individual strandings, disease, injury and old age have have been implicated.

Beachings are, unfortunately, often fatal. In many cases, wildlife veterinarians say that the best procedure is to euthanize stranded whales, even if they are discovered before dehydration sets in. Whales are so massive that they rely on water to support their bodies; on land, the whales’ bulks compress their organs and other tissues, New Scientist notes, flooding their bodies with a protein called myoglobin that is toxic to kidneys. After an hour on land, the kidney damage may be so severe the animals will not survive even if they are returned to the sea.

Orcas do not appear to be an exception to the rule: A 2013 study of North Pacific orca strandings dating back to 1925 found that just 12 percent of killer whales survive being beached, though it was unclear if the other 88 percent had died on the land or at sea — historically few killer whales, the report notes, had necropsies.

Whether or not the video of Morgan shows an actual stranding attempt is uncertain, and the aquarium says that its whales can safely exit the water for short amounts of time. “The orcas at Loro Parque are trained to leave the water on their own accord,” the aquarium wrote in its statement. “This behavior is used for manifold purposes, for example, for presenting the animals to the public, for conducting corporal check-ups, for inspecting their blowholes, as well as for testing hearing abilities of the orcas.”

But the video has resurfaced the controversy around Morgan’s captivity. She is the only wild-born killer whale of the aquarium’s six orcas, all of which are on loan from SeaWorld. Morgan, malnourished and dehydrated, was captured off the coast of the Netherlands in 2010. Many countries have regulations barring capture of marine mammals, but Morgan was taken under a “rescue, rehabilitation and release” permit, according to the Free Morgan Foundation, a group founded by marine biologist Ingrid Visser to advocate for the whale’s release from Loro Parque.

That Morgan remains at Loro Parque has long been a bone of contention, with critics saying that the whale is being held illegally. A paper published in the journal of Transnational Environmental Law in 2012 concluded that “Dutch authorities erred legally in making their final decision” to send Morgan to the aquarium, rather than releasing the animal once she was rehabilitated.

Visser told New Zealand’s that Morgan’s activity in the video is “fundamentally wrong,” adding, “Nowhere in the world do any wild orca slide out onto concrete platforms.”