BEHAVIORAL EFFECTS OF COPPER ON LARVAL WHITE STURGEON.

Early life stage white sturgeon are sensitive to copper with adverse behavioral responses observed during previous studies. The objectives of the present study were to quantify the effects of copper exposure on white sturgeon swimming and feeding behaviors and determine their time to response. Larval sturgeon (1-2, 28 or 35 days post hatch) were exposed to copper (0.5-8 µg/L) for 4-14 days. Abnormal behavioral changes were observed within the first few days of exposure including loss of equilibrium and immobilization. Digital video tracking software revealed decreased swimming activity with increasing copper concentration. Significant changes in behavior and mortality occurred at concentrations of copper between 1-8 µg/L. Juvenile white sturgeon, 58 days post hatch, exposed to 12 µg/L copper consumed 37-60% less food than controls after 3 days of exposure. Our results indicate that behavioral endpoints were more sensitive than some standard toxicity test endpoints and can be effectively expand the sensitivity of standard toxicity tests for white sturgeon. Swimming behavior was impaired to the extent that survival in the field would likely be jeopardized. Such data would provide managers a useful metric for characterizing the risks of copper contamination to white sturgeon. This article is protected by copyright. All rights reserved.