In a highly unusual event, 15 sea lions were shot and killed at a fish farm in Clayoquot Sound after a pack of the large mammals broke into salmon pens and couldn't be scared away.
The incident has been described as "a marine mammal massacre" by environmentalists who want the farm shut down, but a spokesman for Cermaq Canada Ltd. said it hasn't experienced anything like the sea lion invasion before, and steps have been taken to ensure it doesn't happen again.
Bonny Glambeck of the group Clayoquot Action said Monday the slaughter took place over two days in December, after a pack of sea lions broke into the recently reopened Cermaq farm at Binns Island, north of Tofino on Vancouver Island.
The group said the information was released recently by Fisheries and Oceans Canada. The department could not be reached for immediate comment.
Fish farmers are authorized to kill harbour seals and California sea lions that are damaging their operations.
But Ms. Glambeck said farms shouldn't be located in Clayoquot Sound, an area on the west coast of Vancouver Island that is recognized by UNESCO for its rich ecological values.
"This is an internationally recognized wilderness area. It's a UNESCO biosphere reserve, and so this is a place where the natural environment and the animals should take precedence over human activities, especially one that has such a large impact as salmon farming," she said.
"I think the open-net salmon farm sites [in Clayoquot Sound] need to be reassessed," she added. "They should have looked at the siting criteria in terms of what was happening in the surrounding environment – i.e., the sea lions."
Ms. Glambeck said the Cermaq farm had been fallow for a few years, and just weeks after the farm was reopened and stocked with juvenile salmon, sea lions broke into the fish pens.
There are more than 20 fish farms in the Clayoqout Sound area, but in recent years, only three have reported sea lion problems, typically involving single animals that became tangled in nets.
Fisheries and Oceans Canada's records for about 70 fish farms operated by several different companies on the B.C. coast show that, over the past three years, only one other California sea lion has been shot.
That animal was killed at Cermaq's Plover Point farm, which is also in Clayoquot Sound.
In addition, Cermaq reported that three sea lions drowned last year after becoming entangled in nets at its Millar Channel fish farm in Clayoquot Sound, and one drowned at its Barkley farm, in Barkley Sound.
Grant Warkentin, a spokesman for Cermaq, said a pack of sea lions tore through perimeter fences and wouldn't leave once they were inside the Binns Island farm.
He said none of the other Cermaq farms have had any similar incidents, and the site has been given additional, stronger fencing to ensure the incident isn't repeated.
"It was quite unusual what happened," he said. "The winter months are when the sea lions are most common in the area because they are following their food source up the coast. … Even so, we usually don't have issues because we have predator nets that go around the perimeters of all our farms. … But in this case, for whatever reason, they were just very aggressive and were able to breach the system and do a fair amount of damage."
Mr. Warkentin said the animals were damaging equipment and posed a safety risk to fish farm workers, and attempts were made to try to frighten the sea lions away before a decision was made to shoot the animals.
"We try to keep them out passively, but once they get in and start wrecking things, then they kind of get a sense they can do anything they want. And with an animal that large, if it sets its mind to something, it's pretty hard to change it," he said.
Sea lions weigh up to 390 kilograms and grow to more than two metres in length.
"When you have animals that large that have decided they don't want to leave a farm system, it's pretty tough for a small human to convince them otherwise. They tried scaring them away, banging the metal pipes, that sort of thing. But once they figure nothing will happen to them, they just don't leave," Mr. Warkentin said.
"It's unfortunate and we are really sad it had to come to this," he said of shooting the sea lions. "We are quite disappointed this had to happen. We aim every year to have zero negative interactions with any wildlife. We don't want to see this happen at all, ever."