PARENT SESSION

IP11 Investigations of the Columbia River and Estuary (USA)
B113 & B114
8:00 AM - 12:00 PM, Thursday

(IP095) Effects of contaminants on growth and reproduction of white sturgeon in the lower Columbia River.

Webb, M.¹, Feist, G.¹, Gundersen, D.², Foster, E.³, Schreck, C.⁴, Maule, A.⁵, Fitzpatrick, M.³, ¹ Oregon State University, Corvallis, OR, USA² Pacific University, Forest Grove, OR, USA³ Oregon Department of Environmental Quality, Portland, OR, USA⁴ Oregon Cooperative Fish and Wildlife Research Unit, Biological Resources Division, USGS, Oregon State University, Corvallis, OR, USA⁵ Biological Resources Division, USGS, Columbia River Research Laboratory, Cook, WA, USA

ABSTRACT- White sturgeon (Acipenser transmonatus) experience poor reproductive success in many reservoirs of the Columbia River which may be related to environmental contaminants. The objective of this study was to assess the relationship between tissue contaminant concentrations and various physiological parameters of white sturgeon in the lower Columbia River. White sturgeon were captured in commercial fisheries in the estuary and Bonneville, The Dalles, and John Day Reservoirs. Condition factor, relative weight, and gonadosomatic index were determined for each fish. Gonad and liver tissue were examined histologically. Liver, gonad, and cheek muscle were analyzed for total mercury, 18 chlorinated pesticides, and 28 PCB congeners. Plasma was analyzed for testosterone, 11-ketotestosterone, estradiol-17, vitellogenin, calcium, triacylglycerides, and free fatty acids. White sturgeon captured in Bonneville Reservoir had the highest tissue contaminant levels and incidence of gonadal abnormalities compared to fish at the other locations. Plasma triglycerides were negatively correlated with tissue burdens of total DDT, total pesticides, and PCBs. Condition factor and relative weight showed negative correlations with tissue contaminant loads. Males with elevated contaminant load had reduced gonadosomatic indices. Some males and immature females showed elevated plasma vitellogenin; however, elevated levels of vitellogenin were not correlated with any of the contaminants analyzed. In males, plasma androgens were negatively correlated to total DDT, total pesticides, PCBs, and total mercury. These results suggest that environmental contaminants may have an effect on the growth and reproductive potential of white sturgeon, especially males, in the Columbia River.

Key words: reproductive physiology, white sturgeon, growth, environmental contaminants