Wednesday, October 14, 2009

Want more fish? Try doing nothing

At times it seems like we'd be better off without a fish management agency at all. Given their over reliance on hatchery production, and harvest, WDFW certainly bears as much responsibility for declining salmon in Washington as any group. Pink salmon are virtually unmanaged by the state. There are no hatcheries, an harvest is largely limited to tribal and sport fisheries. Despite the fact that pink salmon are unlike anyother species when it comes to their spawner densities and oddyear returning lifehistory we can learn from their example. On the White River where pink salmon numbers have only numbered a few thousand in the past, pink salmon returns have shattered the previous record with almost a half a million this year. Indeed, the Green River has seen a similar spike in pink salmon numbers in the past few run cycles. Such high abundance of spawning salmon brings huge loads of marine nutrients to freshwater ecosystems driving aquatic and riparian productivity.

While the environmental conditions and processes which are leading to the establishment of such large spawning populations are poorly understood, one thing is for sure...We are witnessing salmon at their best, opportunistic species capable of colonizing and filling habitat even after the most destructive catastrophy. Salmon and Steelhead reestablished quickly in the Toutle after it was ravaged by the eruption of Mt St. Helens. Pinks with their high abundance and simple lifehistory are capable of colonizing habitat very rapidly, other species can do the same if given time. On the Willamette and South Fork Skykomish robust populations of Coho have established in the 50 plus years since access to the watersheds became available. Currently both populations are unsupplemented and are essentially left alone. Considering all the money we spend on salmon restoration (we've spend almost 12 billion on the Columbia since 1978), and how little per dollar benefit we typically see, a hands off approach seems highly prudent. Take money out of hatcheries, put it in enforcement and habitat restoration and wait. The fish will respond.

These sort of considerations are often overlooked by production oriented fisheries managers and anglers, however fish's ability to readily recolonize available habitats should be taken into consideration for dam removal projects like the Elwha. Hatchery fish will provide an immediate spike in returns, however given their lack of spawning success in the wild they will likely stunt or delay the process of recolonization. Local adaptation to fill the range of niches available to anadromous salmonids drives long term abundance and stability in stocks. Intensive hatchery supplementation will thwart the ability of wild salmon to find and colonize habitat succesfully.

Another great example of a successful recolonization is on the Cedar River where for 100 years fish were unable to access the upper 30 miles of habitat above Landsburg Dam. In 2003 a ladder was constructed to allow fish to pass into the upper watershed. Thanks to the lobbying efforts of thoughtful researchers at the UW no hatchery fish were planted in the upper Cedar and already populations of Coho and Chinook have established themselves. The process of colonization is ongoing for these longer lived, estuary and stream rearing fish. In 2007 over 400 chinook returned above Landsburg, just 4 years after access was established and given the good numbers of Coho around the sound this year returns should be strong above Landsburg. As more dams come down around our region we have to ask ourselves, do we want the short term benefit of hatchery supplementation or will we allow the process of colonization to occur uninterupted by humans? The fish will deliver if we do.

Seattle Times Coverage of the White River Pinks

Columbia Basin Bulletin Coverage of record Willamette Coho Runs. While the article is titled "though no hatcheries," implying hatcheries normally increase abundance the wild coho are likely doing as well as they are because there are no hatcheries.

Oregonian coverage of the huge amount of money being spent on recovery.

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