802 POJE, GINN, AND O'CONNOR 



Analysis of the various temperature exposures showed significant 

 differences in their mortalities at 24 hr (P <€ 0.001). The data were 

 arranged in five groups according to magnitude of AT and subjected 

 to a multiple range test by the Student— Newman— Keuls procedure 

 to identify homogeneous subsets. Bass exposed to 15.5°C AT (final 

 temperature, 33.6°C) were isolated from other groups by their higher 

 mortalities. At ambient temperature and at 8.3°C AT (final 

 temperature, 26.4°C), survival of bass was greater than at any other 

 AT exposure. The results showed no roe-specific variance. In 

 addition, there were no interactions among variables (roe, batch, test 

 regime, and AT) which generated variances indicative of synergistic 

 behavior. 



The mortality of the barrel-control striped bass, 42.7% at 15.5°C 

 AT (33.6°C), compared favorably with that reported in the 

 literature. Schubel, Koo, and Smith (1976) showed that short-term 

 static exposure ~4 to 6 min of bass to a AT of 15.0°C (35.0°C) 

 resulted in 48% mortality after 24 hr. 



Carp larvae demonstrated a much greater tolerance to AT 

 [Fig. 3(b)]. Absolute controls showed 100% survival to 48 hr. 

 Increased mortality occurred only at temperatures above 16.7°C AT 

 (34.8°C). At 19.4°C AT (37.8°C), 24-hr survival was 1.7% for 

 simulator runs, 1.6% for flow controls, and 3.3% for barrel controls. 

 Over a 1.6°C rise (36.1 to 37.8°C), barrel-control mortality increased 

 by 90%. 



At the 24-hr observation, the test regime to which the larvae 

 were exposed contributed no significant variance to survival 

 (P < 0.194). At 48 hr, however, the carp exposed to turbulent flow 

 in the collection net (simulator runs and flow controls) had a higher 

 mortality rate than those in the barrel controls (P < 0.052). 



Flow Experiments 



Kedl and Coutant (1976) exposed striped bass larvae to passage 

 through a simulated power-plant condenser at 2.1 m/sec and low AT. 

 Their study and ours did not identify any mortality attributable to 

 condenser-tube passage at typical power-plant velocities and low AT. 

 We pursued this line of investigation by additional exposures of bass 

 larvae at ambient temperature, a typical power-plant AT of 11.1°C 

 (28.3°C), and flows of 0.61, 1.22, and 1.83 m/sec. Schubel (1975) 

 calculated that the general condenser-tube velocity was in the range 

 of 1.5 to 2.5 m/sec. 



Responses of striped bass larvae to changing flow velocities varied 

 with temperature exposure. At 24 hr after exposure to ambient 



