Montana Wildlife Officials Cut Deer Tags Amid Disease Outbreak
White-tailed deer in north-central Montana are facing heightened pressure as wildlife managers reduce hunter tag limits in response to recent disease-related mortality. Over the past month, significant die-offs among primarily white-tailed deer have been documented near waterways, linked to viral infections identified as blue tongue virus and epizootic hemorrhagic disease (EHD).
Disease Impact and Distribution
Though the presence of these viruses can vary widely across the landscape, Montana Fish, Wildlife and Parks (FWP) notes that outbreaks can lead to severe localized declines in deer populations. The viruses are particularly prevalent along watercourses such as the Milk, Lower Yellowstone, and Lower Clark Fork rivers, where outbreaks have been reported.
Biological Effects of Blue Tongue and EHD
Blue tongue and EHD are related but distinct viral diseases causing rapid onset of internal hemorrhaging in infected ungulates. Clinical signs include lethargy, loss of appetite, excessive salivation, dehydration, and swelling in areas like the tongue, head, or neck.
- Infected animals typically seek water sources to relieve fever and dehydration, often appearing listless with drooping heads.
- Mortality can occur quickly, with animals dying within days in acute cases or up to two weeks post-infection.
Transmission and Seasonal Factors
These viruses are transmitted by biting midges—small, bloodsucking insects thriving in moist, muddy environments. Peak midge activity coincides with late summer and early fall, intensifying transmission risk. Reports generally decline following hard freezes that drastically reduce midge populations.
This fall’s unusually warm weather has extended midge activity, contributing to more widespread outbreaks, according to Brian Wakeling, Chief of the FWP Game Management Division, and Region 7 Commissioner Bill Lane’s commission report.
Species Affected and Public Health Notes
Blue tongue and EHD have a broad host range worldwide, affecting various wild ungulates such as white-tailed deer, mule deer, elk, moose, bighorn sheep, mountain goats, pronghorn, as well as domestic livestock including cattle and sheep.
Humans cannot contract these viruses; however, FWP advises against consuming meat from animals suspected of infection or feeding such meat to pets to mitigate any potential health risks.
Management Response
In response to these localized outbreaks, wildlife managers are proactively reducing deer harvest quotas to help prevent population declines. Monitoring continues as FWP biologists gather data to assess the ongoing impact of these diseases on Montana’s ungulate populations.
Additional reporting and sources from: State reduces deer tags in areas hard hit by disease | Daily Inter Lake
