In 1994, fish were examined for the presence of bubbles in gill 

 lamella and lateral lines. In June 1994, on certain days, up to 80 

 percent of the fish sampled had bubbles in gill lamella and up to 

 50 percent of the fish sampled had bubbles in the lateral line. Yet, 

 in 1995, no signs of gas bubble trauma are being reported. Yet, the 

 dissolved gas levels in 1995 are substantially higher than they 

 were in 1994. In the NMFS net pen studies below Ice Harbor, in 

 1995 the levels of mortality are much higher than they were in 

 1994. So the question is, why do we see this discrepancy in data. 



I believe there are a number of reasons. One is that in 1994 in 

 examining the fish for signs of gas bubble trauma, they used 90- 

 to 100-power microscopes; in 1995, they are using 10-power mag- 

 nification to look for these signs. Until only recently, no examina- 

 tion for bubbles in gill lamella were being conducted. 



As early as July 1994, the problem of high hydrostatic pressures 

 in the bypass system causing the collapse of bubbles before fish are 

 collected for exsmiination was identified. This problem was later 

 validated through experiments at Battelle Pacific Northwest Lab- 

 oratories. Yet, even to this day, the smolt bypass systems continue 

 to be used as the primary source of fish for assessing the impact 

 of gas bubble trauma. 



I think there is a serious credibility problem with the Smolt 

 Monitoring Program, but I also think there is a more fundamental 

 problem and that is in 1995, the program has been designed with- 

 out an understanding of how fish are distributed in the Columbia 

 and Snake Rivers in relation to dissolved gas levels, the periods of 

 exposure and potential for mortality. As a result, the present pro- 

 gram is an unfocused collection of attempts by various agencies to 

 sample fish without an understanding of the appropriate locations 

 and conditions under which to assess the impacts of dissolved gas 

 supersaturation on Columbia and Snake River salmon runs. 



Finally, I believe if the NMFS expert panel on Dissolved Gas 

 Supersaturation had been directly involved in the design of the 

 monitoring program, we would have had a much more viable pro- 

 gram than we presently have. 



Thank you. 



Senator Kempthorne. Thank you very much. I appreciate your 

 testimony. 



I'd like to now call on Mr. Wesley Ebel. Welcome. 



STATEMENT OF WESLEY EBEL, BIOLOGIST, SEATTLE, WA 



Mr. Ebel. Thank you. 



I'd like to address my comments again to question No. 1 and a 

 little bit on question No. 5. 



The benefits of using controlled levels of spill as a fish passage 

 mechanism are established if there is no other alternative than 

 passage through turbines. Available research indicates that juve- 

 nile salmon will survive at a significantly higher rate passing over 

 a spillway than through turbines at the Columbia River Dam. 

 Thus, spilling water at dams where fish are not collected and 

 transported or where juvenile bypasses are inadequate does have 

 some scientific validity as long as spill volumes are held at levels 

 that do not cause excessive mortality from gas bubble trauma. 



