The whale was discovered by workers before first light Wednesday morning at Mainstream Canada's Ross Point farm, located northwest of Tofino and on the Island's west coast, said company spokeswoman Laurie Jensen.
Although the exact cause of death is unknown, Jensen said the company believes the whale has been dead for time because divers inspected the farm's nets only two days earlier and found nothing unusual.
"It was a very unusual incident, none of our staff, and some of them have been working in that area for 20 years or more, and they've never experienced anything like that," said Jensen.
"It was a bit of a shock and quite a surprise."
After all, no whales have been spotted in the area recently, although some orcas were spotted near a farm in early December, said Jensen.
She said the company believes the dead whale drifted into the farm site and as it decomposed, gases floated the animal to the surface.
While the whale damaged some predator nets, it did not damage any nets containing Atlantic salmon smolts and as a result none of the fish were harmed and none escaped, said Jensen.
She said the whale has been towed to and tied up at a nearby beach.
Jensen said employees of Fisheries and Oceans Canada and local whale researchers have taken over the investigation and a necropsy will likely be performed Friday.
The age of the whale is unknown, but Jensen said local researchers believe the whale is female and is at least 7.5 metres long.
"We really want to see what happened to it and how it died," she said.
-- by Keven Drews in Vancouver
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