(e) = estimate;  * = morbidity, not mortality

Florida Fish and Wildlife Commission (FL), International Bird Rescue Research Center (IBR), USGS National Wildlife Health Center (NW), Southeastern Cooperative Wildlife Disease Study, Athens, GA (SCW), Tri-state Bird Rescue & Research (TS)

Written and compiled by Kathryn Converse-Western US, Grace McLaughlin - Eastern US, NWHC, and Lori Steckervetz Technician. For more information about these and many other wildlife diseases please refer to USGS National Wildlife Health Center Field Manual of Wildlife Disease. To report mortality or receive information about this report, contact the above NWHC staff, or for Hawaiian Islands contact Thierry Work. Phone: (608) 270-2400, FAX: (608) 270-2415 or e-mail: kathy_converse@usgs.gov. USGS National Wildlife Health Center, 6006 Schroeder Road, Madison, WI 53711.

National Wildlife Health Center Quarterly Mortality Report

Trichomoniais in California band-tailed pigeons. From April 1- 28, 2006, sick and dead band-tailed pigeons were found in groves of Canyon live oaks in Whiskeytown National Recreation Area.  Clinical signs in sick birds included weakness, inability to maintain balance or fly very far and isolation from other birds.  Field personnel reported that due to extremely wet conditions in the winter and spring, pigeon flocks were at lower elevations than normal and appeared to be feeding on acorns.  Many of the estimated 5,000 birds in the area during the die-off were migrants moving north, although there is a resident population at that site.  An estimated 300 birds died during the outbreak.  The parasitic disease trichomoniasis was confirmed in 4 pigeons submitted to the USGS National Wildlife Health Center for diagnostic evaluation.  This disease is caused by the single celled protozoan Trichomonas gallinae and is commonly seen in mourning doves at backyard feeding stations.  The parasite causes a cheesy growth in the back of the throat that may interfere with swallowing, causing the bird to regurgitate food which is contaminated with parasites from the oral cavity.  The disease is spread through ingestion of contaminated food or water.  The first documented significant outbreak of trichomoniasis in band-tailed pigeons occurred in California in 1988 when at least 16,000 birds succumbed to the disease.

Martins, swallows and bluebirds die in central US. An estimated 150 purple martins, Eastern bluebirds, and barn swallows were reported dead in multiple locations in Indiana, Illinois, Kentucky and Missouri from mid-April to mid-May.  Extended periods of cloudy weather, cooler than normal temperatures and rain were thought to be a factor in the mortality.  Specimens were received by the USGS National Wildlife Health Center and the Southeastern Cooperative Wildlife Disease Study.  The diagnosis was emaciation suspected to be due to exposure and associated weather conditions.

New report of amphibian disease in Maine. From late April through mid May, approximately 30 sick and dead green frogs were found in an ornamental garden pond on the University of Maine campus in Bar Harbor.  Affected larvae were lethargic, unable to right themselves, wouldn’t swim away and had bubbles in the skin covering their legs.  A USGS National Wildlife Health Center pathologist diagnosed the fungal infection Ichthyophonus sp. in specimens submitted for diagnostic evaluation.  This is the first time this fungus has been documented in this location. 

Botulism returns to Tulare Basin, California.  In early June, 2006, morbidity and mortality was detected in breeding ducks, shorebirds and coots on private lands in Kings and Tulare counties in California near USFWS Kern National Wildlife Refuge (NWR).  Temperatures at the time were in the 90’s.  Sick birds were unable to fly, could not open their eyes and had droopy heads.  Avian botulism was suspected based on the clinical signs, time of year and location.  Coots, mallards, gadwall, white ibis and black-necked stilts were the primary species involved.  USFWS and California Dept. of Fish & Game personnel picked up over 480 birds by June 30 with an estimated 3,500 birds at risk.  The ratio of sick to dead was 2:10.  Avian botulism type C was confirmed in birds submitted to the USGS National Wildlife Health Center.  Although botulism has occurred in the past around Kern NWR, NWHC was not aware of any cases occurring since 1995.  Botulism is an intoxication caused by ingestion of a toxin produced by Clostridium botulinum bacteria.  The bacteria can stay dormant in wetlands until favorable conditions such as warm temperatures; anaerobic environment and a protein source allow it to become active.  Outbreaks can occur annually or sporadically in the same location and may continue for several weeks.