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Breaching dams won't save salmon  -- April 10 2000, Oregonian, Letter to the editor by Don Dodds.   
A March 26th commentary on breaching dams to increase salmon in the Snake River failed to discuss some powerful reasons why breaching those dams won't achieve that result.  First, the commentary did not consider ocean conditions, especially food supply that is essential to survival of Snake River salmon.
 A recent study found that returning salmon declined 90% over the last 30 years in the pristine, undammed and heavily environmentally reconstructed Keogh River in British Columbia. The study concluded the decline was due to a 30-year decline in food productivity in the North Pacific waters where these salmon mature. This is the same ocean area where the Snake River salmon mature.  In the light of this evidence, the construction of the dams on the Snake 35 year ago appears to be unrelated coincidence. By comparison, the prolific salmon stock in the Hanford Reach of the Columbia River feed farther north in colder waters where food supply is adequate. Other evidence shows that ocean conditions, rather than river conditions, are primary salmon survival factors.  For example, fish populations that rely on the same food sources as salmon but do not enter the rivers as salmon show a similar population decline as the salmon since 1883.  Why breach dams to try to increase salmon if the salmon starve to death because of inadequate ocean food supply?  Second, the commentary failed to take predators, especially protected predators, into account. The National Marine Fisheries Services- own data reveals that the populations of many predators soared while salmon populations declined.   For example, seals, sea lions and sea otters (which were slaughtered during the 1800s for oil and furs) increased from about 3000 in the early 1900s to about 650,000 today. Some bird predator populations have increased from a few hundred pairs to over 30,000.  Salmon predators, other than man, kill 99 of every 100 salmon. Those who advocate dam breaching to save protected salmon seem unwilling to make tough choices, such as reducing the population of one protected species to save another. It is hard to defeat the age old relationship between prey and predator.  Without predator control, any increase in salmon production will simply provide an increase in predators, and no net gain of salmon in the river.  Finally, after calling for unjustified dam breaching, the piece urges other drastic controls on human activity along rivers, vigorous habitat restoration, which will likely have little or no impact on salmon populations and may in fact decrease their biodiveristy. A paired river study in British Columbia compares two rivers, one river in disarray due to human activities to a second river where the habitat was been heavily restored according to the latest biological opinion. The biologically repaired river habitat is being out produced by the unaltered and supposed heavily damaged river.  Management of salmon over the past century has concentrated on the hatcheries and harvest while considering the ocean habitat to be an inexhaustible pasture. The success of this approach has been limited. Over the last 10 or 12 years, the idea that the ocean is constant and unbounded has been slowly changing.   In 1995, Congress directed that ocean conditions be considered in salmon survival.  Since that time, considerable evidence has been compiled that indicates the problem is not in the rivers and the current 4H (Habitat, Harvest, Hatcheries and Hydropower) approach will not solve the problem. Is there a need to rush into drastic and irreversible actions that will not save salmon? The tide of biological opinion is changing.  We can have it both ways, save the salmon and the dams.

Don J. Dodds is president of North Pacific Research in Portland. For more information you can contact him at
 dondodds@aol.com.

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