[UPDATE 2: SeaWorld Gave Nursing Orca Valium, Against Accepted Vet Guidelines][UPDATE: SeaWorld Gave Valium To Whales For "Grotesque" Behavior Unnatural In The Wild]  

Trainers at SeaWorld have been documented administering psychoactive drugs to some of their marine mammals, according to new documents obtained by Buzzfeed. The website obtained an affidavit filed in the Ontario Superior Court of Justice in a dispute between the SeaWorld and Marineland over the transport of a killer whale, Ikaika, to SeaWorld.

The documents show that benzodiazepines, a drug that includes the human medications Valium and Xanax, is given to the orca whales to ensure their mental health is stable in captivity. Animal advocates say that mental stress is a result of their being in captivity.

“They do not cope with being kept in these tanks. They survive to some degree, but they don’t thrive to any degree,” founder of the Orca Research Trust, Ingrid Visser, told Buzzfeed. “They show stereotypical behaviors that are abnormal, repetitive behaviors like head bobbing, chewing on concrete, and self mutilation by banging the side of their heads on the side of the tank, and there isn’t a single orca living in captivity where you cannot see one of these behaviors, and in many of them you see multiple examples of these behaviors.”

Spokesperson for SeaWorld Fred Jacobs defended the park’s drug use in a statement:

Benzodiazepines are sometimes used in veterinary medicine for the care and treatment of animals, both domestic and in a zoological setting. These medications can be used for sedation for medical procedures, premedication prior to general anesthesia, and for the control of seizures. The use of benzodiazepines is regulated, and these medications are only prescribed to animals by a veterinarian. Their use for cetacean health care, including killer whales, is limited, infrequent, and only as clinically indicated based on the assessment of the attending veterinarian. There is no higher priority for SeaWorld than the health and well-being of the animals in its care.

This isn't the first time SeaWorld has been targeted for its use of psychoactive medications on orca whales. In a piece for The Dodo in January, "Blackfish" director Gabriela Cowperthwaite noted that whales are often put on diazepam (valium) in an attempt to ease the stress of separation from a mother or child. You can read Cowperthwaite's piece here for more about problems faced by orcas in captivity.