From last year but even more relevant considering we have another year of data
http://www.theardentangler.com/index.php/management-of-cowichan-river-chinook/
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Cowichan River chinook are an important stock on southeast Vancouver Island, with indicator status under the Pacific Salmon Treaty. They typically don’t roam far from home during their ocean lives and when conditions are favourable prefer to stay in the Strait of Georgia, especially the northern half. They are big contributors to the inside recreational chinook fishery and are important to the local First Nation’s food fishery. Although there is some enhancement of this stock the current abundance is largely from natural production with a spawning escapement target of 6500 adults, defined as age-3 or older fish. For some reason this chinook stock also has an unusually large number of age-2 fish returning to spawn but as these are always smaller males they contribute relatively little to production.
After a period of earlier decline Cowichan chinook rebuilt strongly through the 1990’s, with the return peaking at over 14,000 adult fish in 1999. Regrettably it was all downhill after that, with a return in 2009 of considerably less than a thousand adult fish. In response to this rapid decline management measures were put in place in an attempt to reverse the trend, with the implementation in 2006 of large terminal area closures adjacent to the Cowichan estuary and the five restricted zones in the north SoG mixed-stock fishery mentioned earlier. As well, starting in the early 2000’s significant work was conducted in-river to upgrade the habitat and this is thought to have been a major contributor to the current rebuilding trend.
And what a rebuild! Since the low in 2009 the return each fall has steadily increased, meeting the escapement target in 2015 and going more than a thousand adult fish over in 2016. And the return in 2017 was bigger yet, now estimated at 14,698 adult fish or more than twice the spawning escapement target and the outlook for 2018 is similar. Cowichan chinook went from being south coast problem child to gold star status in remarkably short order.
This background is important when considering the decision by DFO this week to keep the remaining restricted zones in the north SoG in effect. There has always been considerable skepticism regarding the effectiveness of these, as anglers have simply learned to fish around them. Acknowledgement of this by DFO stock assessment staff is found in a recent briefing note reviewing sport fishery management for Cowichan chinook that states, “There appears to be no significant change in ER in the northern areas despite 5 spot closures. More analysis is required, but effort appears to have redistributed around the closures with little reduction of impact on stocks of concern.”
The briefing note cites the expected return of Cowichan chinook in 2018 of somewhere between 10 and 15,000 adult fish (or about twice the spawning escapement target), with an additional 2 – 3,000 adult chinook expected as a result of the daily limit reduction for chinook in the Strait of Georgia recreational fishery, an action expected to reduce the exploitation rate on all chinook stocks encountered there by about 30%. The briefing note concludes by stating “The reduction in recreational catch limits is expected to be more effective in reducing the Cowichan exploitation rate than the spot closures” and “There is no evidence which would suggest the expected reduction in ER would change if the northern GST chinook closures were eliminated or adjusted.”
Given all this, one has to question why senior management staff insists on keeping the five spot closures in place because the decision is poisoning the relationship between the recreational fishery and DFO"