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DATA RECORDING 



► Standard data forms appeared cumbersome to use in the field We observed 



that technicians were not sure what data to record, and they had difficulty finding 

 the correct box to record data. 



FISH EXAMINATION 



» Fish should be examined with 26-40X magnification, rather than a 2X lens. We 



observed that bubbles along the lateral line could be seen under a dissecting 

 microscope that were not visible through the head-mounted 2X lens. Your crew 

 at Ice Harbor had both the microscope and the head-mounted lens with them on 

 May 8, but only the head-mounted lens on May 1 1 . 



» The field technicians urgently need a written, detailed protocol on exactly what 



to examine on each fish, and what to record about their observations. For 

 example, at Ice Harbor Dam, many of the dead fish were partially decomposed 

 and GBD signs were not observable, because of the decomposition. Yet. it 

 appeared that these fish were recorded as mortalities that have no sign of GBD. 

 They should be recorded as unexaminable 



► All field crews need to observe fish with known GBD signs, so they can be 

 familiar with vtrtiat the signs look like. We found that the crews both below Ice 

 Harbor Dam and Bonneville Dam were uncertain about whether or not some 

 features they observed in fish were bubbles. 



► Written protocols should also be developed for examinations of invertebrates. 

 Portions of the entire food chain may be affected by gas supersaturation. 

 particularly those organisms that spend time in shallow water. Your crew has 

 observed bubbles in the brood pouch of Cladocerans, so the risk to 

 invertebrates is very real. 



► Fish examinations should be expanded to include the gills and prominent 

 internal vessels, especially since the hatchery Chinook are killed anyway. This 

 examination will require some routine dissecting equipment (scissors, scalpel, 

 probe, pins, cradle), not currently available, as well as a microscope. 



GAS MEASUREMENTS 



Your practice of measuring gas levels at the live cage sites is excellent, and you 

 also need to measure gas levels inside at least one of the live cages below 

 Bonneville Gas levels were measured inside the deep cage below Ice Hartor, 

 but only in the river near the live cages below Bonneville. The netting of the 



