Prepared in cooperation with the U.S. Fish and Wildlife Service Mercury and Selenium Contamination in Waterbird Eggs and Risk to Avian Reproduction at Great Salt Lake, Utah Open-File Report 2015–1020 U.S. Department of the Interior U.S. Geological Survey Cover: Franklin’s gulls nesting at Bear River Migratory Bird Refuge, Great Salt Lake, Utah. Photograph taken by Josh Ackerman in 2012. Mercury and Selenium Contamination in Waterbird Eggs and Risk to Avian Reproduction at Great Salt Lake, Utah By Joshua T. Ackerman, Mark P. Herzog, C. Alex Hartman, John Isanhart, Garth Herring, Sharon Vaughn, John F. Cavitt, Collin A. Eagles-Smith, Howard Browers, Chris Cline, and Josh Vest Prepared in cooperation with the U.S. Fish and Wildlife Service Open-File Report 2015–1020 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2015 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1–888–ASK–USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Ackerman, J.T., Herzog, M.P., Hartman, C.A., Isanhart, J., Herring, G., Vaughn, S., Cavitt, J.F., Eagles-Smith, C.A., Browers, H., Cline, C., and Vest, J., 2015, Mercury and selenium contamination in waterbird eggs and risk to avian reproduction at Great Salt Lake, Utah: U.S. Geological Survey Open-File Report 2015-1020, 164 p., http://dx.doi.org/10.3133/ofr20151020. ISSN 2331-1258 (online) Acknowledgments This research was funded by the U.S. Fish and Wildlife Service’s Environmental Contaminants Program (On-Refuge Investigations Program), with additional support from the Utah Department of Natural Resources’ Forestry, Fire, and State Lands Program, Utah Department of Environmental Quality’s Division of Water Quality, Environmental Protection Agency, U.S. Geological Survey’s Science Support Program, U. S. Geological Survey Western Ecological Research Center, and U.S. Geological Survey Forest and Rangeland Ecosystem Science Center. We thank Bridget Olson, Bob Barrett, Laura Vernon, Cristopher Bittner, Sandra Spence, and Jack Sheets for project support. We thank the Bear River Migratory Bird Refuge (U.S. Fish and Wildlife Service), Timpie Springs Wildlife Management Area (Utah Department of Natural Resources), Farmington Bay Waterfowl Management Area (Utah Department of Natural Resources), Harold S. Crane Waterfowl Management Area (Utah Department of Natural Resources), Antelope Island State Park (Utah Department of Natural Resources), Inland Sea Shorebird Reserve (Rio Tinto - Kennecott Utah), areas near Saltair (Utah Department of Natural Resources), Weber State University, and U.S. Fish and Wildlife Service’s Intermountain West Joint Venture for access and logistical support. We thank Ashley Casey, Trevor Watts, Robin Keister, Nacole Wilson, Stephen Peterson, Bridie Farmer, Matt Stevens, and David Cockerill for field and laboratory work. iii This page left intentionally blank iv Contents Acknowledgments ...................................................................................................................................................... iii Executive Summary .................................................................................................................................................... 1 Introduction ................................................................................................................................................................. 4 Objectives ................................................................................................................................................................... 6 Methods ...................................................................................................................................................................... 6 Field Methods ......................................................................................................................................................... 6 Nest Monitoring and Egg Collection .................................................................................................................... 6 Failed-to-Hatch, Abandoned, and Random Eggs ............................................................................................ 7 Nest Survival and Surrogate Egg Technique ................................................................................................... 7 Egg Survival and Egg Micro-Sampling Technique ........................................................................................... 8 Laboratory Methods ................................................................................................................................................ 8 Egg Dissection and Processing ........................................................................................................................... 8 Mercury Determination ........................................................................................................................................ 9 Selenium Determination ...................................................................................................................................... 9 Egg Contaminant Concentrations on a Fresh Wet Weight Basis ...................................................................... 10 Statistical Methods ................................................................................................................................................ 10 Mercury and Selenium in Eggs .......................................................................................................................... 10 Spatial Hot Spot Analysis .................................................................................................................................. 11 Effects of Mercury and Selenium on Bird Reproduction .................................................................................... 11 Results and Discussion ............................................................................................................................................ 11 Objective 1: Evaluate the Risk of Mercury and Selenium Contamination to Birds Breeding within Great Salt Lake ..................................................................................................................................................... 11 Mercury Concentrations Varied Among Species ............................................................................................... 11 Selenium Concentrations Varied Among Species ............................................................................................. 12 Molar Ratio of Mercury to Selenium Among Species ........................................................................................ 12 Mercury and Selenium Risk to Birds ................................................................................................................. 13 Objective 2: Examine the Spatial Variation in Egg Mercury and Selenium Concentrations among Wetlands of Great Salt Lake ..................................................................................................................................................... 15 Mercury Concentrations Varied Among Wetland Sites ...................................................................................... 15 Selenium Concentrations Varied Among Wetland Sites .................................................................................... 16 Objective 3: Assess the Effect of Mercury on Waterbird Egg Hatchability and Nest Survival at Bear River Migratory Bird Refuge ........................................................................................................................................... 17 Mercury and Selenium Concentrations Versus Egg Volume ............................................................................. 17 Mercury Concentrations in Random Eggs Versus Failed-to-Hatch Eggs and Abandoned Eggs ....................... 18 Effects of Mercury Concentrations on Nest Survival: Surrogate Egg Method .................................................... 19 Effects of Mercury Concentrations on Nest Survival: Micro-Sampled Egg Method ........................................... 20 Conclusions and Management Implications ............................................................................................................. 21 Contaminant Exposure Risk to Breeding Birds .................................................................................................. 21 Wetland-Specific Exposure and Management ................................................................................................... 21 References Cited .....................................................................................................................................................