(a) . Magnitude of observed Mortalities 



The sizes of the various species of fi.5!i collected daring the 

 study varied widely, from juvenile individuals weighing only a few ounces, to 

 large adults weighing nearly 20 pounds . An. "average" size for any species 

 would have been difficult to establish, and misleading. Values for the magjii- 

 tude of the kills are therefore expressed m poinds. 



The heaviest observed mortality for ariy single explosion, including 

 nonmarketable species was 3, 794 pounds, of which only 44 pounds were marketable 

 fish. Other heavy kills were 1, 425 pounds, all noamarketable; 1, 221 pounds, of 

 which 1, 200 were nonmarketable, 1, 000 pounds, all nonmarketable, and in one 

 instance, outside of the regular test area, 540 pounds, of which 515 pounds were 

 marketable fish . Observed kills of marketable species were for the most part 

 light. Table 5 and figure 3 show the percentage frequencies of observed kills 

 by wei^t groups. The kill of marketable fish exceeded 100 pounds in less than 

 8 percent of the observed explosions, and in only 1 of tlie 92 shots fired in the 

 G-ll-C-13 area, was the kill more than 150 pounds. 



(b) . Observed kill vs . weight of charge 



A complete lack of relationship was apparent between weight of 

 the explosive charge and the observed fish mortality. Even superficial examination 

 of the data shows that heavy mortality may result from relaJdvely light charges, 

 while in many instances no kill was observed following tlie heaviest charges. 



(c) . Observed kill vs . depth of charge 



A similar lack of relationship was apparent between the position 

 of the charge in the water; i.e., on the bottom, or w: upended at an intermediate 

 depth. Mortalities of similar magnitude were observed from both suspended and 

 bottom charges . 



Table 5 . Observed kill of marketable fish (lbs .) per shot 



expressed in percent occiixrence 



13 



