Montana Lowers Deer Tags Amid Disease-Related Mortality
On Wednesday, November 20, snowflakes settled gently on a white-tailed deer’s ear at Lawrence Park in north-central Montana, an area now facing wildlife challenges due to disease outbreaks. In response to significant numbers of deer deaths near waterways, state wildlife managers have reduced the number of deer tags issued to hunters.
Recent weeks have seen an increase in fatalities among primarily white-tailed deer attributed to blue tongue virus and epizootic hemorrhagic disease (EHD). These viral diseases, common near riparian zones, have caused concentrated die-offs that are raising concern among biologists and wildlife officials.
Disease Impact and Spread
Blue tongue virus and EHD, while caused by different viral agents, both produce severe hemorrhagic symptoms that often result in rapid mortality. Infected animals may display signs such as lethargy, loss of appetite, excessive salivation, dehydration, and swelling around the tongue, head, or neck.
It is typical for afflicted deer to seek water to ease their dehydration and fever, behaviors that unfortunately make them more vulnerable and often cluster them near water bodies where outbreaks are concentrated. Mortality can occur within days, with some animals dying as quickly as one to two days after the onset of acute symptoms.
Transmission and Environmental Factors
The viruses responsible for blue tongue and EHD are transmitted by biting midges—tiny insects that thrive in damp, muddy environments. These midges inject the virus into susceptible populations of wild and domestic ungulates through their bites.
- The affected species include white-tailed deer, mule deer, elk, moose, bighorn sheep, mountain goats, pronghorn, and livestock such as cattle and sheep.
- Midge populations peak in late summer and early fall, correlating with the timing of viral outbreaks.
- Extended warm weather this fall has likely contributed to increased midge activity and the spread of these viruses.
Wildlife Management Response
Montana’s Department of Fish, Wildlife and Parks (FWP) reports localized outbreaks along the Milk, Lower Yellowstone, and Lower Clark Fork river basins. This pattern is consistent with prior annual occurrences, though the severity fluctuates depending on environmental conditions.
To mitigate potential long-term population declines, FWP is limiting hunting permits in the most affected regions. These measures are precautionary to ensure sustainable deer populations amid disease pressure.
Expert Insight and Precautions
Brian Wakeling, Chief of the FWP Game Management Division, emphasizes that while blue tongue and EHD are common diseases seen every year, they typically remain localized and subside after sudden cold spells that reduce midge numbers. This year’s ‘prolonged, unseasonably warm’ weather has extended the transmission window, increasing mortality.
Humans are not susceptible to these viruses; however, authorities caution against consuming meat from deer suspected of being infected. Additionally, feeding potentially diseased carcasses to pets is strongly discouraged to prevent unintended exposure.
Additional reporting and sources from: State reduces deer tags in areas hard hit by disease | Daily Inter Lake
