Meeting Abstract

P3.125  Thursday, Jan. 6  Effects of Salinity on the Endocrine Stress Response of Trachemys scripta in the Lake Pontchartrain Basin THOMPSON, J.A.*; FRANCK, L.; VALVERDE, R.A.; Southeastern Louisiana University; Southeastern Louisiana University; Southeastern Louisiana University judd.thompson@selu.edu

Environmental salinity in the Lake Pontchartrain Basin has increased due to saltwater intrusion since the latter part of the 20th century. In order to determine the extent to which this affects local wildlife, it is essential to identify and study native species subjected to these changes. As an abundant, non-endangered, freshwater vertebrate, the red-eared slider, Trachemys scripta, was chosen to serve as a bio-indicator of environmental health in the Lake Pontchartrain basin. We tested the hypothesis that turtles exhibit an increased stress response due to increased environmental salinity. We also tested the hypothesis that T. scripta is more abundant in less saline environments. Turtles from low salinity environments showed moderate stress response, turtles from moderate salinity responded robustly, and turtles from high salinity exhibit a reduced response. Our data show that high environmental salinity interferes with the endocrine stress response of the turtle and with corticosterone production. This impairment could mediate the inability of the turtle to adapt to a high salinity environment. This may constrain the distribution of the turtle on the Lake Pontchartrain Basin. It is expected that other freshwater vertebrates may be impacted in a similar way as the turtle. Our study shows that the turtle may serve as good sentinel species for elevated salinity in the Lake Pontchartrain Basin.