Effect of stress on fecal cortisol levels in teleost fish

Various environmental stressors have been implicated in the debilitation and loss of coral reefs worldwide. In this study of teleost fish, two potential stressors, noise and parasite infection, were studied in separate experiments. Both measured fecal cortisol by High Performance Liquid Chromatography (HPLC) as an endpoint. Results in both experiments were analyzed using 95% confidence intervals (∝ = 0.05).; The effects of exposure to underwater boat noise were studied in 25, captivity-adapted Tilapia (Oreochromis mossambicus). Cortisol levels in the first and third stress monitoring periods were greater than in their respective baselines, while the second was not different.; The effects of chronic exposure to protozoan ectoparasites, cf. Uronema and Cryptocaryon irritans, were studied in seven captive parrotfish (Sparisoma viridi). Cortisol levels were greater when the parrotfish demonstrated parasite-related behavior. These results suggest that both noise and parasitic infection can activate endocrine components of the stress response in teleost fish.