Salmon farms proliferate on the B.C. coast and are very contentious because they may be spreading disease among the wild salmon that is the basis of commercial and sports fishing in the Province. According to this article the diseases are also spreading to fresh water species of fish either through spawning salmon or sports fishers -introduced it to the lake on a boat, trailer, or on fishing gear.
Whatever the means of transmission, this is an extremely serious situation that highlights the need for caution introducing Atlantic salmon to Pacific waters, in this case, and anytime a foreign species is introduced. One impetus for introducing fish farming was the decline in wild stocks of salmon and the need to create a new industry.
Florida wildlife are suffering from an invasion of foreign species introduced primarily by the Pet Industry. Iguanas, Pythons, Parrots and other former pets are breeding and competing with indigenous species. For instance, the Alligator is being challenged for its position as top predator in the Everglades by Asian Burmese Pythons.
It seems like the diseases brought along with these invaders contains the danger of species extinction even more so than the competition for food sources. This has far reaching implications for human survival when you consider the importance of the salmon as a food source.
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METRO VANCOUVER - A virus linked to the death of farmed salmon has for the first time been found in B.C. freshwater fish — cutthroat trout in Cultus Lake — a research team reported Thursday.
Researchers say the finding should spur the B.C. government, which is responsible for management of freshwater fish, to launch a thorough study to determine how widespread piscine reovirus (PRV) is and whether it is fatal to native fish.
"This concerns me greatly," said professor Rick Routledge, a Simon Fraser University fish-population statistician. "The province needs to pay attention to this because we have evidence it is found within freshwater fish."
The Canadian Food Inspection Agency announced this week it would be testing B.C. wild salmon to determine the status of three salmon diseases: infectious haematopoietic necrosis, infectious pancreatic necrosis, and infectious salmon anaemia.
"PRV is not on their list," Routledge noted in an interview.
Evidence of PRV was found in 13 of 15 sampled fish. Follow-up analyses further confirmed the virus' presence in these fish and identified their genetic sequencing as 99 per cent identical to Norwegian strains, casting doubt on the virus being native to B.C.
In an interview, Routledge said it is possible that endangered Cultus Lake sockeye introduced the virus to the freshwater trout when they came upstream to spawn. PRV has also been found in B.C. in farmed salmon and wild salmon.
Another possibility is that someone introduced it to the lake on a boat, trailer, or on fishing gear.
"It's there, that's the concern," Routledge said. "And we know it can infect several different species (of Atlantic and Pacific salmon). It could be getting into all sorts of other fish populations, as well."
Cultus Lake is also home to rainbow trout, kokanee and Dolly Varden.
lpynn@vancouversun.com
Researchers say the finding should spur the B.C. government, which is responsible for management of freshwater fish, to launch a thorough study to determine how widespread piscine reovirus (PRV) is and whether it is fatal to native fish.
"This concerns me greatly," said professor Rick Routledge, a Simon Fraser University fish-population statistician. "The province needs to pay attention to this because we have evidence it is found within freshwater fish."
The Canadian Food Inspection Agency announced this week it would be testing B.C. wild salmon to determine the status of three salmon diseases: infectious haematopoietic necrosis, infectious pancreatic necrosis, and infectious salmon anaemia.
"PRV is not on their list," Routledge noted in an interview.
Evidence of PRV was found in 13 of 15 sampled fish. Follow-up analyses further confirmed the virus' presence in these fish and identified their genetic sequencing as 99 per cent identical to Norwegian strains, casting doubt on the virus being native to B.C.
The virus has been linked to heart and skeletal muscle inflammation, a disease that has reportedly become widespread in Norwegian salmon farms and can lead to fish mortality.
Also involved in the research discovery were Fred Kibenge, a virology professor at the Atlantic Veterinary College in Prince Edward Island, and Stan Proboszcz, a fisheries biologist with B.C.'s Watershed Watch Salmon Society.In an interview, Routledge said it is possible that endangered Cultus Lake sockeye introduced the virus to the freshwater trout when they came upstream to spawn. PRV has also been found in B.C. in farmed salmon and wild salmon.
Another possibility is that someone introduced it to the lake on a boat, trailer, or on fishing gear.
"It's there, that's the concern," Routledge said. "And we know it can infect several different species (of Atlantic and Pacific salmon). It could be getting into all sorts of other fish populations, as well."
Cultus Lake is also home to rainbow trout, kokanee and Dolly Varden.
Independent fish researcher Alexandra Morton, a vocal opponent of salmon farming, announced in April that supermarket-purchased farmed salmon had tested positive for PRV.
"We have to think carefully about we're doing, putting fish farms in the middle of salmon migration routes, where they are an ideal places for these viruses to thrive." Routledge said.
lpynn@vancouversun.com
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Source:
Discovery of deadly salmon virus in freshwater fish puts pressure on B.C. to conduct wider study
Link:
http://www.vancouversun.com/technology/Discovery+deadly+salmon+virus+freshwater+fish+puts+pressure+conduct+wider+study/6959173/story.html
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