Improve smolt barging 



Some salmon are collected at McNary, 

 Little Goose and Lower Granite dams, then 

 transported in special barges past the 

 downriver dams. They are released below 

 Bonneville Dam to continue their journey to 

 the ocean. 



The current barge transportation system 

 began in 1981 . At the time, it was consid- 

 ered an interim measure to move smolts past 

 the dams until diversion screens were in 

 place. 



G, 



ver the years, the Corps of Engineers 

 and regional fishery managers have analyzed 

 the benefits of transportation. The conclu- 

 sion: benefits vary widely among salmon - 

 species. Steelhead and fall chinook appear to 

 benefit the most. Benefits for spring and 

 summer chinook and sockeye are less clear. 

 Generally, scientists agree that transporting 

 salmon around the dams can increase sur- 

 vival under some conditions. 



In the immediate years ahead, barging is 

 one of the few tools the region has to im- 

 prove salmon survival, particularly in 

 low-water conditions. Barge transportation 

 of salmon should be improved immediately 

 to boost salmon survival in the near term. 



In our fish and wildlife program, we call 



on the Corps of Engineers to expedite im- 

 provements in transportation. Cooler water 

 and less crowded conditions in the barges, for 

 example, may help reduce stress and improve 

 survival. When the fish are released from 

 barges below Bonneville Dam, survival may 

 increase if the fish are dispersed more widely 

 in the lower river. This could help them avoid 

 predators and adapt to river conditions. 



Control salmon predators 



Conditions in the modem Columbia and 

 Snake rivers, because of the dams, are ideal 

 for salmon predators, particularly squawfish. 

 They thrive in the warm, slow-moving water 

 of the reservoirs. 



Other factors also favor salmon predators. 

 For example, hatchery smolts sometimes are 

 weakened by disease or don't know how to 

 avoid predators. Smolts are easy prey below 

 dams because they are stunned after passing 

 through the turbines. 



One solution to this problem is to reduce 

 the number of predators. Our strategy calls 

 for reducing the squawfish population by 20 

 percent. Experts believe this cbuld lead to a 

 25-percent reduction in predation. 



1916-1920 ■ 



Columbia River salmon canneries reach their 

 peak production: 550,000 cases per year, 

 48 pounds per case. 



