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The death of an orca calf in the waters off B.C. and Washington state has transfixed the world.

That's because the mother, and now members of her pod, are keeping the deceased animal's body afloat after more than a week.

Meanwhile, a prominent orca researcher, Paul Spong, has alleged that the calf's death could be connected to open-net salmon farming on the B.C. coast.

The founder of OrcaLab on Hanson Island said that's because a virus produced in coastal aquaculture called PRV, a.k.a. piscine orthoreovirus strain PRV-1, is harming chinook salmon.

"The explanation about the baby’s death has a lot to do with the depletion of chinook salmon," Spong said in a news release. "The presence of fish farms and viruses that they’re sharing has a lot to do with that."

In May, federal fisheries biologist Kristi Miller coauthored a paper noting that "various strains of PRV have been associated with diseases in Pacific salmon".

In particular, the research team looked at HSMI-like disease and jaundice/anemia associated with PRV-1 in farmed Atlantic and Chinook salmon.

"The two diseases showed dissimilar pathological pathways, with inflammatory lesions in heart and skeletal muscle in Atlantic salmon, and degenerative-necrotic lesions in kidney and liver in Chinook salmon, plausibly explained by differences in PRV load tolerance in red blood cells," they reported.

The research team also suggested "that migratory Chinook salmon may be at more than a minimal risk of disease from exposure to the high levels of PRV occurring on salmon farms".

Centre for Whale Research

The B.C. Salmon Farmers Association, on the other hand, has claimed that the recent research into PRV is "problematic" and must be "looked at with a critical eye in the context of extensive science done on this topic".

"The report presumes the presence of a virus equates to disease, when in fact the virus is common but the fish on our farms are not sick," the association's chair, Vincent Erenst, said in a news release in May. "Much like humans, it's normal that fish are naturally exposed to numerous viruses every day without adverse effect."

Filmmaker and writer Mark Leiren-Young recently wrote an article on Straight.com indicating that southern resident orcas are starving from a lack of chinook.

He cited orca experts who've argued that removing dams along the Snake River could provide better opportunities for chinook salmon to spawn and for their population to increase. This, in turn, would provide a lifeline for the endangered southern resident orcas.