Upper Midwest Environmental Sciences Center

Studies indicate that fish-eating wildlife are most at risk from elevated mercury exposure. Yet, definition of the total mercury concentration in water and forage fish that are protective of fish-eating wildlife remain in question. The U.S. Geological Survey, Wisconsin Department of Natural Resources, and the University of Wisconsin are collaborating on research designed to assess the risks to wildlife from exposure to mercury in their environment. The risk assessment focuses on the common loon (Gavia immer), which is considered to be a sentinel or indicator species that can provide early clues about negative impacts on the natural environment.

The purpose of the study is to provide natural resource and industry managers with information to predict mercury concentration in adult loons, egg, and chicks based on known site conditions in a breeding lake. The two primary goals of the project are to: (1) develop a model that accurately predicts common loon mercury exposure under differing environmental scenarios and (2) quantify the level of mercury exposure that negatively affects common loon reproduction and survival. This information can then be used in the development of regulatory goals for mercury emissions and water quality standards that protect sensitive wildlife species.

Publications and reports that describe our findings are listed below:

Fournier, F., W. H. Karasov, K. P. Kenow, M. W. Meyer, and R. K. Hines.  2002.  The oral bioavailability and toxicokinetics of methylmercury in common loon (Gavia immer) chicks.  Comparative Biochemistry and Physiology A 133:703-714.
             
Fournier, F., W. H. Karasov, M. W. Meyer, and K. P. Kenow. 2002. The daily energy expenditures of free-ranging common loon (Gavia immer) chicks.  Auk 119:1121-1126.

Kenow, K. P., S. Gutreuter, R. K. Hines, M. W. Meyer, F. Fournier, and W. H. Karasov.  2003.   Effects of methyl mercury exposure on the growth of juvenile common loons.  Ecotoxicology 12: 171-181.

Karasov, W. H., K. P. Kenow, M. W. Meyer, and F. Fournier.  2007.  Bioenergetic and pharmacokinetic model for exposure of common loon chicks to methylmercury.  Environmental Toxicology and Chemistry 26:677–685.

Kenow K.P, Meyer M.W., Hines R.K., Karasov W.H.  2007.  Distribution and accumulation of mercury in tissues and organs of captive-reared common loon (Gavia immer) chicks.  Environmental Toxicology and Chemistry 26:1047-1055.

Kenow K.P, Grasman K.A, Hines R.K., Meyer M.W., Gendron-Fitzpatrick A., Spalding M.G., Gray B.R.  2007.  Effects of methylmercury exposure on the immune function of juvenile common loons.  Environmental Toxicology and Chemistry 26:1460-1469.

Kenow, K. P., M. W. Meyer, and W. H. Karasov,  R. K. Hines, K. A. Grasman, and A. Gendron-Fitzpatrick.  2007.  Final Report: Assessing the ecological risk of mercury exposure to common loons.  Provided to the Wisconsin DOA per Focus on Energy grant titled ''Assessing the Ecological Risk of Mercury Exposure to Common Loons''.

Fournier, F., Karasov, W.H., Kenow, K.P., Meyer, M.W.  In Press.  Growth and Energy Requirements of Captive-Reared Common Loon (Gavia immer) Chicks.  Auk 124(4).

Pollentier, C. D., K. P. Kenow, Meyer, M.W.  In Press.  Common loon (Gavia immer) eggshell thickness and egg volume vary with pH of nest lake in northern Wisconsin.  Waterbirds (scheduled for late 2007 issue).

Principal Investigator: Kevin Kenow