HENRY, B.A.; WOOD, W.B.; CHEEK, A.O.; Southeastern Louisiana University; Southeastern Louisiana University; Southeastern Louisiana University: The Reproductive Physiology of Warmouth Sunfish Spawning in Pristine Vs. Contaminated Environments
The goal of this study was to determine the physiological and ecological impact of chronic exposure to polyaromatic hydrocarbons (PAHs) among warmouth sunfish (Lepomis gulosus) that inhabit two bayous within the Lake Pontchartrain Basin. The experimental site, Bayou Trepagnier, is contaminated with a high level of petroleum by-products found within its bottom sediments. For means of comparison, uncontaminated Stinking Bayou was chosen as a reference site due to its similar water quality and surrounding vegetative cover. The study had two specific aims: (1)Estimate exposure of adult warmouth to compromised water quality by a mark-recapture study. (2)Characterize the reproductive cycles of male and female warmouth during the breeding season to discover evidence of endocrine disruption. I hypothesized adults would display site fidelity during the breeding season and reproductive hormones and vitellogenin would be depressed in Bayou Trepagnier. Results indicate that 67% of adult warmouth captured in Bayou Trepagnier remained in the contaminated environment despite changes in water quality over the study period. Preliminary data show no significant difference in steroid hormones and vitellogenin found in males and females between the experimental and control locations. Testosterone levels of warmouth in Bayou Trepagnier averaged 1.73ng/ml in males and 2.94/ml in females, while in Stinking Bayou males averaged 2.27ng/ml and females 2.38ng/ml. Vitellogenin concentrations in Bayou Trepagnier averaged 226.93ug/ml in males and 2113.67ug/ml in females, while comparatively warmouth inhabiting Stinking Bayou yielded 223.02ug/ml among males and 2109.36ug/ml in females. The hormone and vitellogenin results indicate endocrine disruption is not presently occurring among populations of warmouth sunfish inhabiting Bayou Trepagnier.
