Friday, June 25, 2010

"What makes a good coach is knowing what the result is supposed to look like"-Vince Lombardi as told to John Madden

The Aleknagik system, feeding into Bristol Bay, Alaska is one of the few unspoiled habitats for salmon in the world. Nick's prior exposures to salmon habitat were the Columbia River system (95% salmon population decline due to excessive damming (Grand Coulee, Chief Joseph, Rocky Reach, Wanapum, the Dalles, and several other hydroelectric dams), the Klamath River (hundreds of miles of salmon habitat isolated by two main stem dams) and California (all rivers have been dammed and water diverted). Aleknagik has been studied continuously since 1946 by the University of Washington. Through sediment boring, the health of the habitat for sockeye salmon has been extended to the last glacial period. The evidence from all of the research is that the sockeye population is as large as or larger than it was thousands of years ago, despite the substantial annual harvest taken by Bristol Bay fisherman for the past 130 years. Climate warming may be the cause for the improvement, given that Aleknagik has exceedingly short summers (ice out begins May 30 and ice returns towards the end of September)


The importance of Aleknagik to caretakers of salmon in the lower forty-eight is that this is what the restored environment should look like. Some of the critical research findings, all of them eye-openers to Nick, are:


  1. Aleknagik Lake itself (one of four interconnected lakes) provided an opportunity to sample twenty nine separate sockeye groups. They overwhelmingly demonstrated phenotypic variation mostly as a function of spawning habitat. For example, two adjacent populations ( creek and beach spawners respectively) showed dramatic variation in phenotype, but the beach population was almost identical to another beach group over 50 kilometers distant;
  2. Sockeye spawn in three distinct landforms, beaches, small creeks, and rivers.
  3. Spawning sockeye come onto their redds at different times during the overall spawning run.
  4. Each river and creek has a large annual variance in numbers of fish, but there is very little covariance. The result is a stable annual escapement of sockeye from the system into the Bristol Bay fishery. The positive result for the fishing industry is that closure of the fishery is only likely once every forty years. The northern California salmon fishing fleet can be properly envious.


Thinking carefully about these findings, evolutionary adaptation by the sockeye to the fine gradations of its environment has stacked the deck (selected for) species survival in a big range of possible adverse conditions. Also, it appears that the "action" is in the small creeks more than in the rivers. The creeks provide numerous protected, quiet pools where smolt can grow. Thus, when salmon restoration programs in the lower forty eight focus only on placing salmon in large rivers, failure is likely.


The trout-addicted fly fisherman also should take careful note of the Aleknagik system. Rainbow trout, Dolly Varden, Arctic Char, and Arctic Grayling are all dependent on salmon eggs and decaying carcasses for their most significant growth. Trout have evolved a tricky adaptation, given that they typically require warmer habitat to thrive than salmon, who seek colder water. Trout swim rapidly from their lairs to gobble up salmon eggs in colder water, and quickly return to warmer water.


Finally, even bird fans can take lessons from the Aleknagik story. Tree swallows that next closer to salmon runs produce more chicks and sustain a higher survival rate than more distant nesting birds. The insect biomass consumed by the swallows is larger near decaying salmon due to resulting nutrients that favor micro-invertebrates.

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