Mule Deer Mortality
Contact: Brian Kenner, (605) 433-5260
Contact: Eddie Childers, (605) 433-5263
BADLANDS NATIONAL PARK, Interior, S.D. — Wildlife managers at Badlands National Park are closely monitoring the mule deer population. To date, a total of thirty mule deer have been discovered dead within the park. During the past six weeks, Badlands National Park staff collected carcasses and diagnostic samples from multiple dead mule deer following three large snowstorms.
On April 7, biologists transported two fresh carcasses along with blood, ticks and lice from six previously captured mule deer to the Colorado State University Veterinary Diagnostic Laboratory (CSUVDL) for necropsy and diagnostic analysis. One of the mule deer carcasses sent to the CSUVDL was previously captured by park staff in early March and had lost almost 20% of its body weight during the three weeks between capture and death. Common characteristics of these affected deer include; lethargic behavior, drooping ears, large numbers of ticks and lice, ruffled and unkempt hair coats, weight loss, and death. Young deer were most severely affected.
Results from the diagnostic tests include:
No evidence of exposure to or infection with Anaplasma marginale (anaplasmosis).
Moderate to heavy infestation with ticks (Dermacenter apbipictus and Ixodes spp.) and an exotic louse (Bovicola tibialis). The majority of ticks found were D. albipictus "winter tick", which is common to the northern, eastern, and western parts of the U.S.
Multiple positive serology titers for Epizootic Hemorrhagic Disease (EHD) and Blue Tongue Virus (BTV) though no post-mortem signs of these diseases. This indicates past exposure to but not likely current infection with these pathogens.
We do not know exactly what initiated these mortality events; however, a combination of factors probably contributed to the deaths. Factors likely include: extreme weather conditions; food stress coming out of winter into spring; presence of ectoparasites; and possibly other disease factors. We have not observed mortalities in the past two weeks. Please report any sick or dead deer observed within Badlands National Park to: Eddie Childers, 605.433.5263, Greg Schroeder, 605.433.5269, or Josh Delger,605.433.5267. We will continue to provide updates as new information becomes available to us.