Ken Pearce throttles back on his outboard motor, his boat slowing as it cuts through the waters of the lower Fraser River near Steveston, B.C.

He's spotted a half-dozen seals swimming in a side channel.

"They've fed on the rising tide and now they're coming in to soak up the sun and snooze," he says.

Pearce views the animals as a major threat to migrating salmon and the endangered killer whales that feed on them.

He wants tens of thousands of them killed in a commercial hunt.

Pearce, along with Haida Gwaii elder Roy Jones, co-chairs the Pacific Balance Pinniped Society, a group established in July that includes some First Nations, commercial and sport fishers and the fur industry.

"Pinniped" is the scientific term for the family that includes seals and sea lions.

Hundreds of harbour seals are visible swimming near the mouth of the Fraser River looking for salmon. (Chris Corday/CBC)

Pinnipeds put salmon numbers at risk: study

There are more than 100,000 seals in B.C. waters, along with tens of thousands of sea lions.

Pearce said the quickest way to reverse declining salmon numbers is to kill tens of thousands of them, reducing their numbers by 50 per cent.

But that's where the debate gets as murky as the waters of the Fraser.

He cites a study that concludes pinnipeds are eating more than 600 metric tons of chinook salmon every year in Washington state waters alone.

That adds up to millions of fish that could be harvested by humans, set aside for killer whales, or allowed to spawn.

Earlier this year, lawmakers in the U.S. approved an expansion of an ongoing cull of sea lions that prey on salmon and steelhead in West Coast rivers.

WATCH: Hundreds of sea lions fight for food inside fishing nets in B.C.'s Strait of Georgia

Hunt won't help salmon, critics say

Pearce believes the idea of a bloody slaughter in B.C. waters has kept the Department of Fisheries and Oceans and politicians from endorsing his group's plan.

"They are cute, I'm the first to agree, but see 80,000? Are they cute anymore? No, they're a nuisance."

But Peter Ross, vice-president of research at Ocean Wise, questions Pearce's assumptions.

"I don't know if there's any good predator control study that's ever demonstrated that killing off a predator has led to more prey," Ross told CBC News.

Critics of a hunt or cull, including Peter Ross of Ocean Wise, say the plan won't help salmon numbers increase on the B.C. coast. (Martin Diotte/CBC)

He said the food web is complex, and worries a hunt would disrupt the balance between seals, salmon and other creatures.

Ross said the decline in salmon is linked more to habitat destruction and climate change than increases in seal populations.

But frustration is clear in those calling for a hunt.

Could killing seals help killer whales?

Gary Biggar, regional director with the Mé​tis Nation of B.C., supports the idea.

He also fishes commercially and says he's seen first hand an explosion in numbers since the federal government ended the B.C. seal hunt in 1970.

"I work on a seine boat now and I've seen the population skyrocket, and it's getting worse and worse," he says.

Biggar said it's not a big leap to believe B.C.'s endangered southern resident killer whales would benefit.

The whales are in trouble, in part, due to a lack of their primary food, chinook salmon.

Ken Pearce, a sports fisherman, and Gary Biggar, a commercial fisherman, are both proponents of a seal and sea lion hunt in B.C. (Chris Corday/CBC)

He accuses environmentalists and governments of focusing on other problems, rather than acknowledging the impact of seals and sea lions on salmon.

"They've created it by protecting these animals to the point that now we either protect seals or we do something to save the killer whales and our salmon resources."

Biggar and Pearce insist on calling it a harvest rather than a cull, saying they have markets for seal pelts and meat lined up and people willing to hunt and process the animals.

They say they would welcome further scientific study to prove, or disprove, the impact of a seal hunt on salmon stocks.

Tens of thousands of sea lions and more than 100,000 seals live on the B.C. coast. (Associated Press)

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