WATCH: Bored stiff - Monotonous daily life of a killer whale in SeaWorld revealed
A time-lapse video has been posted online, showing a SeaWorld orca floating in the same spot for six minutes prior to performing in a show.
The only movement that the mammal makes is an almost imperceptible turn to the left.
Marine vet, Dr Heather Rally who works with PETA told Metro.UK that this lack of movement is "very very uncommon in the wild."
"It’s believed to be the result of chronic stress, boredom and inhibition of natural behaviors that occurs as a result of inadequate living conditions at places like SeaWorld," she said.
Dr Rally added that this type of stationary behaviour could make the mammal more prone to insect bites and sunburn.
However SeaWorld San Diego have countered these assertions, saying that the orca is merely resting.
"You see, like all animals, killer whales do rest.
"‘The resting behavior in the video is a natural behavior seen in the wild.
"For example, the Southern Resident ecotypes have been seen resting as much as 10-21pc of the time," a spokesman said.
The video was recorded by Superpod, a group who campaign for killer whales to be released from captivity.