Effects of chronic, low concentrations of dietary methylmercury on the behavior of juvenile great egrets
The authors measured the behavioral effects of methylmercury on 16 great egret chicks (Ardea albus) in a captive dosing experiment. Birds were randomly divided into a control group and groups that received 0.5 or 5 mg methylmercury chloride per kilogram of food at between 12 and 105 d of age. They recorded activity levels, maintenance behavior, and foraging efficiency and determined that mercury affected activity and maintenance behavior. Birds dosed with 5 mg/kg became severely ataxic and were euthanized by 12 weeks of age. The authors found that, during the postfledging period, there were no differences between low-dose and placebo birds in time required to capture live fish in pools or in efficiency of capture. They did find that low-dose birds were less likely to hunt fish. Their results suggest that, at the 0.5 mg/kg concentration in food, there are significant effects of methylmercury on activity, tendency to seek shade, and motivation to hunt prey.
- Research Organization:
- Univ. of Florida, Gainesville, FL (US)
- OSTI ID:
- 20006624
- Journal Information:
- Environmental Toxicology and Chemistry, Vol. 18, Issue 9; Other Information: PBD: Sep 1999; ISSN 0730-7268
- Country of Publication:
- United States
- Language:
- English
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