A visiting marine biologist says a false killer whale in the care of the Vancouver Aquarium is harming itself. 

Chester the false killer whale was rescued near Tofino, B.C. and was deemed non-releasable after being treated at the Vancouver Aquarium, where he now resides permanently. 

Ingrid Visser, a marine biologist from New Zealand, visited Chester on Thursday and said she saw signs of self-harm.

"Chester has some self mutilation on him," said Visser. "You can see it on his jaw and open wounds. Looks like he's been doing it for a while."

"This is the sort of thing you see in all captive whales and dolphins and they just shouldn't be kept in concrete tanks."

But when CBC showed pictures of Chester to whale and dolphin specialist Robin Baird, he said there's nothing to be concerned about. 

"I don't think I can see anything which would suggest the animal is self mutilating," said Baird. 

"It seems like a bit of a stretch."

Baird said the false killer whale is still young, and a little clumsy, which is normal as he explores his environment and his new roommate, Helen the white-sided dolphin.

Troy Neale, marine mammal coordinator at the Vancouver Aquarium, says Chester has been doing great since he moved in.

Neale said the aquarium monitors Chester "from tip to tail" every day and will continue to do so.

With files from Tina Lovgreen