The killer whale found dead off the B.C. coast this week suffered blunt force trauma to the head, the Department of Fisheries and Oceans revealed Thursday. 

That could indicate J34, a member of the endangered southern killer whale population, was struck and killed by some kind of vessel, spokesman Paul Cottrell said.

"We're looking into all avenues and circumstances and that's something that will be investigated going forward," Cottrell told CTV News.

"We've brought the skull over to Vancouver and are looking to get a CAT scan on that."

The orca was found floating near the Sunshine Coast community of Sechelt on Tuesday. At 18 years old, the cetacean is considered to have been in the prime of his life.

A necropsy was conducted Wednesday evening but the cause of death has yet to be confirmed. Fortunately, the carcass was in good condition when it was discovered.

"This animal was very fresh and we're optimistic that will really help for getting good results in terms of potential causes," Cottrell said.

Some of the tests will take months to get back, but J34's body condition seemed good in preliminary results, according to the DFO.

That would be an improvement from the summer, when the killer whale was spotted looking underfed by the U.S.-based Center for Whale Research, a group that's been sounding the alarm about the southern resident population's food supply for years.

J34 was the fourth member of J-pod to die this year, and the researchers fear the cetaceans aren't getting enough salmon.

"All fisheries management options should be considered including catch limits and strategic dam removal to recover endangered wild salmon populations," Kenneth Balcomb said in a release.

Together, J, K and L pods make up the southern resident population, whose numbers have dropped about 20 per cent over the last two decades, down to 79.

The animals were listed as endangered in 2005.

Cottrell thanked the Sechelt First Nation for assisting in the recovery of J34's carcass, a challenging and potentially dangerous operation conducted in rough waters, as well as for facilitating the necropsy. The orca's skeleton was left in their care for ceremonial use.

He also applauded the people who reported sightings of J34, noting the DFO is able to obtain much better information from recently deceased cetaceans.

Anyone who sees a marine mammal dead or distressed is asked to contact the DFO's 24-hour hotline at 1-800-465-4336.

With a report from CTV Vancouver's Julie Nolin