(e) = estimate * = morbidity and mortality

Alamosa/Monte Vista National Wildlife Refuge, CO (AM);California Dept. of Fish & Game-Wildlife Invest. Lab (CA); U.S. Fish and Wildlife Service, Ft. Myers, FL (FW); Nat'l Wildlife Health Center (NW ); Idaho Wildlife health Lab, Caldwell, ID (ID); National Veterinary Services Lab, Ames IA (NVSL); U.S. Fish and Wildlife Service, Portland, OR (OR); Rose Lake Wildlife Disease Lab, MI (RL); Southeastern Cooperative Wildlife Disease Study (SC); Wisconsin Department of Natural Resources (WI).

Written and compiled by Kathryn Converse, Kimberli Miller, Linda Glaser, Terry Creekmore, and Audra Schrader, National Wildlife Health Center (NWHC). To report mortality or if you would like specific information on these mortalities, contact one of the following NWHC staff: Western US Kathryn Converse; Eastern US--Kimberli Miller; Hawaiian Islands--Thierry Work. Phone (608) 270-2400, FAX (608) 270-2415 or E-mail kathy_converse@usgs.gov. National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711.

Quarterly Mortality Reports

Amphibian die-offs that occurred this spring in Maine, Minnesota, North Carolina, Massachusetts, and Tennessee have been attributed to iridovirus infection. Affected species included spring peepers, wood, bull, and mink frogs and spotted salamanders. Iridovirus was previously documented as the cause of amphibian mortalities in Arizona (1996), Canada (1997), Utah and North Dakota (1998) and Idaho and Wyoming (1999). In addition, chytrid fungus has been implicated as the likely cause of boreal toad mortality in Colorado's Rocky Mountain National Park. This fungus was responsible for boreal toad die-offs in the park and other regions of the state in 1999.

Salmonellosis, a common cause of songbird mortality in the US, continues to impact birds in several states. Die-offs were reported from Michigan, North Carolina, Tennessee, Washington, West Virginia, and Wisconsin with mortality occurring in a variety of species commonly associated with bird feeders. Widespread songbird die-offs were reported earlier this year in the eastern and Midwestern United States.

Strong winds blew 3 unbolted electrical power transformers from their utility poles spilling approximately 240 gallons of mineral oil-based insulating fluid into a series of small ponds in Barton, Oregon. Eight mallards and at least 2 nutria were impacted by the unusual spill. Four of the affected ducks died while the remainder were cleaned and released. It is unknown if mortality occurred among the nutria inhabiting the ponds.

Tick paralysis was reported from an American Robin and a Chipping Sparrow submitted to the Southeastern Cooperative Wildlife Disease Study for evaluation. An engorged Ixodes brunneus tick was found on each bird. Several species of ticks are associated with tick paralysis but I. Brunneus is the primary tick known to cause this condition in birds. Paralysis is caused by a neurotoxin secreted by the tick's salivary glands, and prompt removal of the tick usually results in full recovery of the animal if no associated traumatic injuries have occurred.

For additional information please contact Dr. Scott Wright, USGS National Wildlife Health Center - Disease Investigations Branch Chief, at 608-270-2460 or Paul Slota, USGS National Wildlife Health Center - Support Services Branch Chief at 608-270-2420.