49 



— . 



1 JOHN VLASTELICIA 



2 death was preceded by an laablllCy to switD and avoid 



3 predators for periods up to 20 minutes after stricken. 



4 Therefore, some loss of wild fish must certainly occur 



5 from abnormally high predation, such as from seagulls or 

 5 other fish-eating birds. In view of the number of fish 



7 observed in these areas and of the demonstrated frequency 



8 of toxic conditions, it is concluded that significant 



9 numbers of juvenile salmon are killed during migration 



10 in these areas. 



11 The chemical tests associated with the 



12 bioassays showed that a number of conditions develop in 



13 the zone of acute pollution which either individually or 



14 in combination may cause fish mortality. These included 



15 conditions of low dissolved oxygen, low pH, and high 



16 sulfite waste liquor content, but most often implicated 



17 in these mortalities were the toxic gases produced by 



18 sludge bed decomposition. 



19 BENT HIC S TUDIES 



20 While juvenile salmon are indirectly 



21 damaged by the sludge beds, the bottom-dwelling communities 



22 near the mills experienced considerable direct adverse 



23 effects. 



24 The bottom life or benthos is an important 



25 segment of the marine community and includes many of the 



