Will hatchery Chinook reared in net pens actually help recover killer whales? Probably not

Southern Vancouver Island anglers propose Chinook net pens off Sooke BC as a solution to the food supply needs of Southern Resident killer whales.

Southern Vancouver Island anglers have proposed Chinook net pens off Sooke, BC as a solution to the food supply needs of  Southern Resident killer whales.

Its interesting that this group of anglers aggressively opposed possible restrictions to their Chinook fishing season and expressed the hardships they were having to endure (Times Colonist, June 25, 2016) by not being able to keep trophy Chinook larger than 82 cm. This is despite the knowledge that early Fraser Chinook returns appear to be the lowest on record, that FN food fisheries will likely be closed, that conservation goals will likely not be met, and that killer whales may face the lowest spring-summer Chinook abundance ever. There is also growing evidence that hatchery-reared fish only replace wild salmon, they don’t recover them, and that net pen rearing comes with a host of other concerns.

There is also no evidence that enhancing late-timed Chinook from Nitinat hatchery will help whales. Stock ID done on salmon eaten by SRKWs shows (via scale remains) these whales are in the Salish Sea targeting Chinook that return primarily to the Fraser.  For the whales, rebuilding early-timed wild Chinook salmon populations in the Fraser appears, by far, to be the best investment. This is definitely the best investment for salmon conservation, and strong arguments this is also the best investment for fisherman.

It’s possible that whales might eat some of these enhanced fish, but for anglers to adamantly continue catching the weak, depressed Chinook runs we know Southern Residents eat, reveals this proposal to be about enhanced Chinook for anglers. If they were concerned for whales, they wouldn’t have had such an adverse reaction about letting depressed spring and early summer Chinook runs reach their spawning grounds. This is not a solution for whales or for salmon. It’s a quick fish enhancement project for recreational anglers that want to keep catching Chinook, and DFO identified it as such.

Original article by Amy Smart, Times Colonist, June 25, 2016. Read article at the Times Colonist.

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Coastal wolf with a salmon in its month.
Photo by Dene Rossouw.