Field Notes
U.S. Fish & Wildlife Service
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2004 Report Available for Abnormal Amphibian Monitoring Project in Region 3
Midwest Region, January 1, 2005
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A final report is now available for the 2004 monitoring efforts for abnormal amphibians on national wildlife refuges and other Service lands in Region 3.

National attention focused on malformed amphibians in 1995 when a group of school children in Minnesota discovered a large number of abnormal and misshapen frogs. In 1997, based on this and an increasing number of reports of abnormal amphibians, Regions 3 and 5 of the U.S. Fish and Wildlife Service collaborated in developing a methodology for monitoring malformed frogs on national wildlife refuges (NWRs) and wetland management districts (WMDs).

The objectives of the monitoring were to determine whether this phenomenon was occurring on FWS lands, to develop a database that would include land use surrounding FWS amphibian monitoring sites, and to contribute to the overall knowledge of the regional and national distribution of the phenomenon. That year, 41 field stations (34 national wildlife refuges and seven wetland management districts) in Region 3 conducted preliminary searches for abnormal frogs. In 2000, the FWS's Environmental Contaminants Program (currently Environmental Quality Program) received funding as part of the Department of Interior's Amphibian Initiative. The assessments originally done in Regions 3 and 5 (1997) were refined and expanded into a nationwide assessment of more than 43 refuges in 31 states. As of December, 2002, 85 refuges in 40 states have been monitored at least once through this project. 2004 Results 2004 was the fifth year of field work for this nationwide project in Region 3. Up to this 2004 season, Region 3 has sampled frogs at 13 refuges/wetland management districts. Sampling consists of collecting frogs from a minimum of two different sites per refuge and examining the frogs for abnormalities. Each refuge is sampled at least two years, and most of them three years, depending on the incidence of abnormalities. In 2000, 2001, and 2002, abnormal frogs were sent to the USGS's National Wildlife Health Center in Madison, Wisconsin for radiograph analysis of the abnormalities. In 2003 and 2004 a subset of abnormal frogs from five different refuges were sent to the University of Wisconsin at LaCrosse for parasitology analysis. A final parasitology report covering frogs from 2000-2003 for the entire country is included as an appendix to this report. In addition, all abnormal frogs from the 2004 field season were sent to Mike Lannoo at the Muncie Center for Medical Education at Ball State University for radiograph analysis. A description of those radiographs is found in Appendix I of this report. Again this year, the Bloomington Field Office (with assistance from the East Lansing Field Office) coordinated the project for Region 3. Staff, volunteers and interns from each refuge also provided invaluable support. Through this collaborative effort nearly 1,000 amphibians from 8 refuges and wetland management districts were collected and examined this summer.

The refuges visited include: Muscatatuck NWR (IN), Clarence Cannon NWR (MO), Two Rivers NWR (IL), Crab Orchard NWR (IL), Upper Mississippi River NWR, McGregor District (IA), Shiawassee NWR (MI), Horicon NWR (WI), Litchfield WMD (MN), Fergus Falls WMD (MN), Ottawa NWR (OH), Union Slough (IA) and Seney NWR (MI). Most abnormalities encountered were missing digits, feet, and limbs. Several animals with atrophied, bent, skin webbings or misshapen limbs were also found. At several refuges there was evidence of the parasitic trematode Ribeiroia (which has been shown to cause developmental abnormalities) although the intensities were fairly low. The one animal with significant skin webbing between its thigh and calf contained 197 individual specimens of Ribeiroia (skin webbings are a common malformation attributable to Ribeiroia).

For a copy of the report, please contact Robin McWilliams-Munson at the Bloomington, Indiana Ecological Services Field Office.

A fact sheet developed in March of 2003 by the Division of Environmental Quality in the Washington Office is also available (including online at the FWS national web site under the Environmental Quality Program) and briefly describes the project and its objectives.

Contact Info: Larry Dean, 612-713-5312, Larry_Dean@fws.gov
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