Montana Chronic Wasting Disease Surveillance and Monitoring - 2021 Season Review

Abstract

Montana, Fish, Wildlife, and Parks (FWP) has been conducting surveillance for Chronic Wasting Disease (CWD) since 1998, and first detected CWD in wild deer in 2017. In 2021, FWP prioritized sampling in northwestern, southwestern, south central, and east central Montana. Additionally, FWP continued to target sampling in the Libby CWD Management Zone and conducted a Southwest Montana CWD Management Hunt for a 2nd consecutive year. Surveillance and management efforts focused on maximizing the detection of CWD in new areas, limiting the spread of CWD, maintaining or reducing prevalence of CWD in endemic areas, improving CWD communication and outreach with the public, and providing hunters the opportunity to have their harvested animal tested for CWD. During the 2021 season, FWP tested 8,525 samples from mule deer (n=3,532), white-tailed deer (n=3,991), elk (n=951), and moose (n=51). Of these, 323 animals tested positive and CWD was detected in 4 new hunting districts (317, 330, 340, and 700). Among positive hunting districts, prevalence estimates between 2017-2021 ranged from Between 2017–2021, CWD prevalence was 6% (95%.CI:.5-7%) in white-tailed deer within the Libby CWD Management Zone and 21% (95% CI:19-23) in white-tailed deer within the Southwest Montana CWD Management Hunt Area. For 2022, FWP will continue to promote proper carcass disposal and transport regulations and advocate sample collection by hunters. Additionally, CWD management actions will be evaluated for addressing high CWD prevalence areas across the state.