REYES, J.A.; GALIMA, M.M.; SAK, K.; SCHLENK, D; KELLEY, K.M.; California State University at Long Beach; California State University at Long Beach; California State University at Long Beach; University of California, Riverside; California State University at Long Beach: Endocrine and Metabolic Parameters of Stress and Growth in Two Southern California Flatfish Species Subjected to Varying Environmental Levels of Municipal Waste

We have initiated a series of studies to define the physiological impacts of municipal sewage outflows along the Orange County coast in two flatfish species, English sole (Parophyrs vetulus) and hornyhead turbot (Pleuronichthys verticalis). Fish were caught by trawling at sites representing varying distances from municipal sewage outflows, followed by collection of blood serum, liver, and other tissues. As the physiological response to catching itself is likely to include elevated levels of stress hormones, there may be several physiological alterations secondary to stress that need to be considered prior to making comparisons between the different collection sites. In our initial experiments, we have observed that fish sampled >30 min after netting exhibit substantially greater serum cortisol levels as compared with fish sampled within 20 min. Serum glucose concentrations show a similar relationship with time after netting. Therefore, data generated thus far indicate that catching-related stress is likely to be an important factor in analysis of the putative physiological changes associated with site-associated environmental contamination in this study. Additional endocrine and metabolic factors and observed site-associated differences will be discussed. [Support in part by California Sea Grant College Program grant NOAA NA06RG0142 2001-02, project 43-F-N]