-J.0 »»■' 



•V* ■'•6.» 



V-V* ■^»» 



"io »K 



"^o »K 



Figure 25. — Exploration of the interaction surface formed by the ratio of the standard length to (a) head length, (b) last 

 dorsal spine length, (c) first dorsal ray length, and (d) second anal spine length of pinfish exposed to three levels of 

 temperature and three levels of radiation for 45 days. 



2,090 rads at 18° C. We assume, therefore, 

 that the accumulated doses used in the present 

 study on this species (865 and 1,335 rads) are 

 sublethal because most organisms can tolerate 

 larger amounts of chronic irradiation than 

 acute radiation. 



Temperature appeared to control the growth 

 of irradiated and unirradiated fish more than 

 salinity or radiation. In general, as tempera- 

 ture increased, the growth of the fish increased. 

 Temperature is known to control the distri- 

 bution, reproduction, growth, and meristic 



structure of aquatic animals. The action of 

 temperature in the aquatic environment is of 

 particular concern, since most poikilo thermic 

 fishes have body temperatures very close to 

 that of their surrounding medium. Steam and 

 nuclear powerplants, as well as other water- 

 using industries, often increase temperatures 

 in rivers and estuaries. Since pinfish are win- 

 ter spawners, it is possible for postlarvae to 

 enter an area of relatively high temperature 

 in the estuary. From the findings of this study, 

 and assuming that the postlarvae would enter 



46 



