What’s behind the killing and beheading of West Coast sea lions?

Is illegal killing of wild animals to harvest parts for black-market sales behind the death and decapitation of four West Coast sea lions?

Federal Fisheries and Oceans (DFO) officials are investigating the recent discovery of a headless Stellar sea lion washed up on a beach near Campbell River, on Vancouver Island.

"We’ve got another situation of a sea lion that’s died [and] that’s had its body parts removed, head in this case," DFO spokesman Paul Cottrell told CBC News.

It's the fourth such incident on Vancouver Island since late November. Three of the dead and mutiliated animals, apparently shot, were found in the Campbell River area, on the island's east coast, and a fourth further south near Comox, the Campbell River Mirror reported.

“We’re very concerned – we want to find out who’s doing this and put a stop to it,” Paul Cottrell, DFO's marine mammal co-ordinator, told the Mirror.

Sea lions can grow to more than 10 feet long and weigh more than a ton, so decapitating one would not be easy, he said.

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"It would be a messy job," Cottrell told the Mirror, adding the investigation is complicated by questions of where and when they were killed before washing up on the local shoreline.

CBC News reported that in one of the cases the poacher had failed to completely remove the head but that whiskers from the head were missing, as was skin from the animal's back.

Sea lion skin and whiskers are sometimes used in aboriginal culture to make items such as drums and masks. But taking animals for that purpose requires permit and each kill must be reported to DFO, CBC News said.

Cottrell told the Victoria Times Colonist last December, after the first three dead animals were found, that they had nothing to do with an authorized First Nations sea-lion harvest.

"Under the licence conditions they have to report the kill and ... typically, we don't have Steller sea lions on the licence," Cottrell said, adding killing Stellers is permitted in rare instances involving animals in northern areas.

The National Post reported in January that while the traffic in illegally harvested antlers and bear gallbladders used for traditional Asian medicine remains a problem, wildlife officers are concerned about the increasing trade in eagle parts and feathers used for costumes worn by aboriginal dancers.

As many as 1,000 eagles a year were being poached for their feathers, officials told the Post.

The Alberta and B.C. governments have programs that allow aboriginal people to acquire feathers from eagles that die naturally. But there are not enough to meet the demand, fuelling the black market where an array of feathers can cost thousands of dollars, the Post said.

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Fish-farm operators are allowed to shoot sea lions and other marine mammals if they're threatening their sea-going net pens. The Time Colonist said DFO statistics show two sea lions were shot between April and June last year.

The practice is controversial. Environmentalists were upset recently when charges against one Norwegian-owned B.C. fish farm for killing 65 sea lions and several seals in 2010 were dropped.