PHYSIOLOGY AND PESTICIDE PROGRAM 



Edward Chin, Program Leader 



Experiments to determine nutritional requirements of brown shrimp, 

 Penaeus aztecus, and white shrimp, P. setiferus, continued. An einalysis of 

 respiration rates in these species was completed, and the final report is being 

 prepared. Work concerning the effects of environmental factors on the growth, 

 survival, and behavior of estuarine organisms was delayed because of a per- 

 sonnel shortage. 



Studies initiated last year on the effects of pesticides on estuarine 

 species continued. Results show that most of the chemicals used to control 

 insect pests along the Gxilf coast are toxic at low concentrations to many in- 

 shore species. The extent to which pest-control practices affect the abun- 

 dance of estuarine species either directly or through effects on their food 

 supply can not be ascertained merely by noting the toxicity of pesticides in 

 the laboratory. It is also necessary to determine the extent of pesticide con- 

 tamination in the estuarine environment. Analysis of pesticide residues in 

 animal tissues and in estuarine waters and soils is therefore being plcinned 

 as a complement to studies to be undertaken in the forthcoming year. 



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