Montana Sheep Conflicts Examined

Montana Sheep Conflicts Examined

CHASE ADAMS
ASI Senior Policy and Information Director

A meeting of the minds in Big Sky Country called for greater sharing of research into the conflicts that arise from the interaction of domestic and wild sheep within the state (and throughout the west).

The Montana Wool Growers Association in partnership with the Montana Wild Sheep Foundation and the Montana Department of Fish, Wildlife and Parks held a symposium on sheep in the state – domestic and wild. The symposium, conducted Feb. 9-10, in Helena, Mont., was largely focused on current research and field observations into conflicts between domestic and wild sheep, with an emphasis on state management of bighorn sheep in Montana and Nevada.

The symposium was well attended by sheep producers from Montana, as well as representatives from the Colorado Wool Growers Association and ASI.

Following a welcome from Montana Lt. Gov. Mike Cooney, Montana Wool Growers Association President Dave McEwen gave an update on the state’s sheep and wool industry. While sheep numbers have dropped significantly in the last century, the past two years have seen a 2 percent increase in the sheep population, signaling optimism in the industry. McEwen cited the challenges the domestic industry faces from environment, nutrition and animal stress, and correlated that those same challenges that domestic producers manage might also be present and unaddressed in wild sheep populations. McEwen closed with a call to action that all sides ensure statements to the press and the public are based on science and truth, not incendiary rhetoric.

The state of the domestic industry was followed by a review of the state of wild sheep populations by Montana Game Management Bureau Chief John Vore and Montana Wild Sheep Foundation representative Kurt Alt. Vore discussed the challenges in connecting populations of bighorn sheep within Montana to achieve genetic diversity while limiting the spread of disease from bighorn population to bighorn population and maintaining separation from domestic sheep.

He further expanded the difficulty his agency faced in meeting the 10-year Montana Bighorn Sheep Conservation Strategy, calling for the establishment of five new wild sheep herds in the state by 2020. Alt focused on the challenges of maintaining separation in a state where 70 percent of the land is privately held, posing concerns by separation advocates that a focus solely on domestic sheep on public lands would not be enough to avoid future die-offs. 

The remainder of the symposium zeroed in on research and wildlife management. Don Knowles, Ph.D., Maggie Highland, Ph.D., and J. Bret Taylor, Ph.D., were given a brief 30 minutes combined to provide an update on the research conducted at the U.S. Sheep Experiment Station in Dubois, Idaho, and the Animal Disease Research Unit at Washington State University. This was followed by the research of Tom Besser, Ph.D., WSU and Wild Sheep Foundation Chair in Wild Sheep Disease Research, and updates on wild sheep initiatives underway in British Columbia (Canada) and Nevada.

Besser presented research indicating that while there are other theories, the presence of mycoplasma ovipneumoniae (Movi) is highly correlated to bighorn sheep die-offs. This conclusion presents a conundrum to researchers as other presentations confirmed that Movi was present in a number of wild sheep herds across the west. This leads to questions by domestic sheep advocates as to whether separation was effective given the spread of the disease from within wild sheep populations and the frequency of wild sheep augmentations, physically transplanting individual wild sheep from one herd to another. Moreover, Besser discussed increased non-specific or specific host resistance as an action item that should be further researched.

While significant die-offs occur in certain wild sheep populations, others appear to have greater resistance to the same pathogens. As Highland noted, the disease is not transmitted, the infectious agents (at present Movi) are transmitted and the result might be disease, putting greater focus on the stressors that McEwen discussed as having an effect on domestic sheep health.

Peregrine Wolff, DVM, and Mike Cox from the Nevada Department of Wildlife reported similar experiences in their state’s herds, where 85 percent of the land is public interspersed with parcels of private land. While Nevada maintains separation between domestic sheep allotments and wild sheep habitat, several disease events they noted can be anecdotally traced to small private land domestic sheep flocks. With more than 900 Nevada wild sheep captured and tested, the Nevada Department of Wildlife found many of their herds to be Movi positive, but found no seeming correlation to the location of domestic sheep. That said, they again expressed a correlation between the presence of Movi and wild sheep die-offs.

The second day of meetings again looked at continued research, focused this time on Montana specifically.

Whit Stewart, Ph.D., Montana State University Extension Sheep Specialist, talked about the nutritional needs of sheep species and the levels or absence of necessary minerals in Montana’s natural landscape, necessitating the need for domestic sheep producers to augment in order to meet nutritional needs of their flocks to maintain health. He closed by urging both wild and domestic sheep interests to work together to find a solution forward, a sentiment echoed throughout the two-day symposium.

Enhancing the conversations on Montana’s experience in building wild sheep herds, Robert Garrott, Ph.D., Montana State University Department of Ecology, presented his research and observations.

Garrott pointed out that Montana State University has extensive sampling on soon to be 1,000 wild sheep. He noted that some of the die-offs he’s explored were caused by novel or spillover events and others might have been caused by “resident pathogens” already existing in the herd. This fact calls into question how many of the die-offs during the past four decades have been caused by resident pathogens rather than spillover events.

“Who knows,” was the answer.

He also noted that most of the wild sheep herds he researched in Montana had Movi and pasteurella leukotoxin bacteria present. While he cited separation between domestic and wild sheep as a way to minimize pathogen transmission, he also mentioned that the Rocky Mountain Front wild sheep herd, which has been the source of many reintroductions, has all of the pathogens present. The conclusion being that it is almost impossible to have confidence that you have a Movi free wild sheep herd, making relocations highly risky because you are guaranteed to move pathogens.

At the end of the symposium, the only fact that remained clear is the need for greater research into disease strains and the transmission of infectious agents. The symposium hosts agreed to create a working group between the Montana Wool Growers, Montana FW&P and Montana Wild Sheep Foundation to continue discussions and ensure the health and viability of wild and domestic sheep.

With Montana State University’s extensive sampling of wild sheep populations, they are an important resource in the path forward and the groups engaged in this symposium approved a memorandum of understanding with the Agriculture Research Service in Pullman, Wash., to share information – a clear sign that collaboration is underway and a win for everyone engaged in this issue.