THERMAL ECOLOGY AND STRESS: 



A CASE HISTORY FOR RED-SORE DISEASE 



IN LARGEMOUTH BASS 



GERALD W. ESCH and TERRY C. HAZEN 



Department of Biology, Wake Forest University, Winston— Salem, 

 North Carolina; and Savannah River Ecology Laboratory, Aiken, 

 South Carolina 



ABSTRACT 



The stress concept is analyzed and related to individual, population, and 

 ecosystem levels of biological organization. Red-sore disease, produced by the 

 gram-negative bacterium Aeromonas hydrophila, is discussed in terms of its 

 relationship to stress. An effort is made to relate seasonal changes in red-sore 

 disease to environmentally induced alterations in the physiology and behavior of 

 largemouth bass. A hypothesis is proposed to explain these interactions in terms 

 of stress. 



ANALYSIS OF THE STRESS CONCEPT 



The operative word in the title of this symposium is stress, yet we 

 question whether many investigators have anything more than an 

 intuitive notion of what it means. To estabhsh a common ground and 

 to set the stage for a discussion of our own work in this area, we feel 

 we should first briefly discuss the concept of stress and consider its 

 application at various levels of biological organization. We hope that 

 the discussion of stress at individual and ecosystem levels of 

 organization is not misconstrued as an effort to rediscover the wheel. 

 The following conceptualization of stress represents our amalgama- 

 tion of the ideas and notions presented by Selye (1950; 1956), Brett 

 (1958), Slobodkin (1967), Odum (1969), Cairns (1976), and 

 Gibbons (1976). 



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