State Eying Respiratory Disease In Local Bighorn Sheep
By Ryan L. Darr, Assistant Chief of Information, New Mexico Department of Game and Fish, Used with Permission from Questa Del Rio News Editor’s Note: A Sept. 8, Taos News story, Respiratory disease detected among bighorn sheep, prompted the Questa del Rio News to reach out to New Mexico Department of Game and Fish officials for more information.
In the winter of 2022, the New Mexico Department of Game and Fish discovered the Mycoplasma ovipnuemoniae bacteria in a bighorn sheep ram that died near the Questa ranger station. The bacteria has been present in the nearby Rio Grande Gorge population of sheep since 2020, it is implicated in bighorn sheep respiratory disease, and it can spread to wild bighorn via direct contact with domestic sheep and goats – the likely source of this spillover occurrence.
The department suspects that the bacteria may be linked to a decrease in lamb recruitment since its appearance two years ago. The diseased ram east of Questa was infected with the same strain of bacteria found in sheep living along the Rio Grande Gorge. This development prompted a collaring and sampling effort of bighorn sheep in the Red River corridor along New Mexico 38 in March 2022. While no one handled or observed sheep exhibiting symptoms of respiratory disease during the two days of capture, we did detect that some individuals had been exposed and were actively infected with the bacteria. Many of these sheep move seasonally between the Red River corridor and Gold Hill, which is considered a subpopulation of the Wheeler Peak bighorn herd. The department’s aerial and ground surveys on Wheeler Peak this summer indicated an increase in the minimum known number of bighorn sheep but also indicated an active respiratory disease event throughout their range from Taos Pueblo to Gold Hill. We predict that the respiratory disease observed results from the same strain of bacteria we have found in other area sheep populations, but will be submitting biological samples collected by our hunters to confirm. Coinciding mortalities have been documented and one of the 14 ewes that were collared in March 2022 has died.
The department has concerns about established Mycoplasma ovipnuemoniae bacteria in the Rio Grande Gorge bighorn sheep herd and from recent transmission to bighorn sheep in the Red River corridor, Gold Hill, and likely Wheeler Peak populations. We believe the bighorn sheep in the nearby Latir Mountain herd are currently unexposed to the bacteria.
The department continues to be concerned about contact between wild sheep and domestic sheep and goats and the introduction of new respiratory bacteria strains.