 |
Commercial Fishingnews, events, and other information for the commercial fishing, aquaculture, and seafood industries |
 |
Article Categories
Business Tools
By
Published: January 23, 2011
Print
Email
Scientists have found that Pacific salmon are now contending with a viral infection possibly similar to leukemia and lymphoma. A team of federal and university researchers have been looking at the genetic signatures of sockeye salmon in British Columbia’s Fraser River, and have found that huge numbers of salmon with a particular genetic signature are dying before they reach their spawning grounds. The study, which was published on 13 January in the journal Science, states that "The mortality-related signature reflects a viral infection." Viruses inject their own genetic material into living cells, tricking those cells into replicating the virus.
The study found that compromised salmon that appeared to have a viral infection at sea were 13.5 times more likely to die before spawning than healthy fish. Co-author Scott Hinch at the University of British Columbia describes the phenomenon as “dead fish swimming.” “There is no doubt there is some form of pathogen involved," Hinch said.
However, Hinch and his team do not yet know just what the virus is, when and where the fish are being infected or how much other factors, such as the huge rise in river water temperatures seen in the past decade, are contributing to mortality. The viral signature was found in many of the fish long before they entered the river. This suggests the infection may be related to "dysfunction," which could explain why so many sockeye now enter the Fraser weeks early, when river temperatures are higher than those to which the fish are adapted.
Some speculate that the possible virus may be linked to fish farms, but others say it could be a natural threat to Pacific salmon. There are plenty of other factors at play, including in the warming river temperatures, food availability, as well as competition and interaction with salmon from Alaska and Japan in the Gulf of Alaska, which may also be carrying and sharing viruses.
"It introduces a whole a bunch of questions about just how extensive this is," says Brian Riddell, a former top Canadian federal fisheries scientist who is now CEO and President of the Pacific Salmon Foundation, a non-profit group working to restore salmon stocks. “…[B]ut then (the record salmon run in) 2010 has got to give you some hope,” says Riddell.
source: Fishlink Sublegals
Submit Article
Published: January 23, 2011
Print
EmailScientists have found that Pacific salmon are now contending with a viral infection possibly similar to leukemia and lymphoma. A team of federal and university researchers have been looking at the genetic signatures of sockeye salmon in British Columbia’s Fraser River, and have found that huge numbers of salmon with a particular genetic signature are dying before they reach their spawning grounds. The study, which was published on 13 January in the journal Science, states that "The mortality-related signature reflects a viral infection." Viruses inject their own genetic material into living cells, tricking those cells into replicating the virus.
The study found that compromised salmon that appeared to have a viral infection at sea were 13.5 times more likely to die before spawning than healthy fish. Co-author Scott Hinch at the University of British Columbia describes the phenomenon as “dead fish swimming.” “There is no doubt there is some form of pathogen involved," Hinch said.
However, Hinch and his team do not yet know just what the virus is, when and where the fish are being infected or how much other factors, such as the huge rise in river water temperatures seen in the past decade, are contributing to mortality. The viral signature was found in many of the fish long before they entered the river. This suggests the infection may be related to "dysfunction," which could explain why so many sockeye now enter the Fraser weeks early, when river temperatures are higher than those to which the fish are adapted.
Some speculate that the possible virus may be linked to fish farms, but others say it could be a natural threat to Pacific salmon. There are plenty of other factors at play, including in the warming river temperatures, food availability, as well as competition and interaction with salmon from Alaska and Japan in the Gulf of Alaska, which may also be carrying and sharing viruses.
"It introduces a whole a bunch of questions about just how extensive this is," says Brian Riddell, a former top Canadian federal fisheries scientist who is now CEO and President of the Pacific Salmon Foundation, a non-profit group working to restore salmon stocks. “…[B]ut then (the record salmon run in) 2010 has got to give you some hope,” says Riddell.
source: Fishlink Sublegals
Submit Article