Pondering The Future Of Taku River Salmon

Taku River photo by Commander John Bortniak, NOAA Corps

Juneau-based commercial fisherman Jev Shelton penned an interesting column in the Juneau Empire about the status of salmon runs in the nearby Taku River.  It doesn’t paint a good picture.

Here’s Shelton with more:

Dire expectations for Southeast Alaska Chinook salmon in 2018 anticipate total returns near or below the worst on record. Taku River Chinook arguably are the poorest performing stock. Less than one-fourth of the minimum escapement goal is predicted; it is the worst prediction in a long downward trend. Obviously, even greater fishing restrictions will follow.

Biologists cite extremely poor marine rearing conditions for the widespread shortage. Fair enough. But don’t be misled. Poor ocean survival does not account for the entire Taku shortfall. Mismanagement of the Canadian in-river fishery, initiated in 1980 for leverage in salmon treaty negotiations, clearly has impacted Taku Chinook. Among the faults in that fishery are unreliable harvest accounting, inappropriate fishing time, and manipulation of the mark-recapture system that estimates spawning escapements. The very real effects from mishandling this fishery compound the very real results of low ocean survivals.

At least as troublesome is the parallel decline of Taku River sockeye. That reduction, covering more than 10 years, is unlike the steadier trend in other northern Southeast sockeye systems. As with Chinook, actions in the Canadian fishery have impacted Taku sockeye abundance.

Analysis by four fishermen in 2016 demonstrated that Taku sockeye escapements have been exaggerated significantly. This inaccuracy occurred in tagging sockeye at Canyon Island and calculating escapement from the proportion of tags caught in the Canadian fishery (mark-recapture). That system was badly flawed. It did not account for tags simply shed, lost to predation or, especially, caught but unreturned by Canadian fishermen. Those sockeye (or Chinook) inappropriately were assumed to spawn successfully and thus falsely inflated the calculated escapement and total allowable catch. Consequently, Alaskan harvests appeared to be less than allowed and escapements appeared greater than needed. All other fishery indicators were inconsistent with those appearances. After review, ADFG staff agreed that the mark-recapture system overestimated escapements and required substantial revision. Currently, the agency is implementing needed corrections.

The cyclical nature of salmon runs good and bad means it’s no time to panic, but some very interesting points are being made by Shelton.