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A dead newborn male orca found on a Far North beach had been mutilated after its death by someone skilled with a knife, a university expert has found.
The 89kg killer whale was missing its head, tail, dorsal and right pectoral fin when it was found south of Waipapakauri Ramp on Ninety Mile Beach on July 5.
Its right side was also cut open but it's not clear whether the mutilation was carried out at sea or by someone on the beach.
Massey University veterinary pathologist Wendi Roe usually sees several dead baby marine mammals each year, including two pilot whale babies so far this year, but has never seen one "chopped up" like this one.
"We do see babies who have died in storms soon after birth but I've never seen one mutilated in this way. We also see adults with bits chopped off but not babies," she said.
Mutilation of the orca's body was performed by someone skilled in using a knife, she believes.
The mammal would have been two to nearly three metres long if the head and tail had remained intact.
Changes in the baby's lungs showed the orca had probably drowned but it's unknown whether it died in a storm or was caught in a fishing net.
Department of Conservation marine species manager Simon Banks said although it was not an offence to accidentally kill an orca, failure to report a death and mutilation after death are offences. That was because they are rare or endangered.
