Decision puts bighorns at risk

The Bureau of Land Management (BLM) released a proposed decision that threatens both bighorn sheep populations and Gunnison sage-grouse habitat. The project will reauthorize domestic sheep grazing in areas that overlap with bighorn herds, increasing the risk that sheep will transmit a deadly respiratory disease. 

Domestic sheep are asymptomatic carriers of several pathogens that can spread quickly through bighorn herds and cause a fatal type of pneumonia. 

“We’ve seen entire herds of bighorn sheep wiped out in different parts of the West and even go extinct in local areas because of these diseases,” said Erik Molvar, executive director of the Western Watersheds Project.

The BLM’s decision will allow private livestock owners to continue leasing nine public land grazing allotments for domestic sheep across the Gunnison Basin and the surrounding Hinsdale and Ouray counties. These grazing permits cover 65,710 acres and will extend for at least 10 years. 

Over 80% of the Sapinero Mesa Allotment and the entirety of the Goose Creek Allotment are considered occupied and critical habitat for Gunnison sage-grouse. The proposed decision will increase the number of domestic sheep on these allotments, where grazing may affect habitat quality, critics say.

According to the Environmental Impact Statement (EIS) that accompanied the decision, cheatgrass invasions are a problem on both allotments, where it dominates plant cover and reduces native diversity. A healthy, diverse variety of forbs and perennial grasses is necessary habitat for the sage-grouse during all stages of nesting and brood-rearing. 

Although the permit requires herders to avoid grazing in mapped bighorn sheep summer habitat, it will allow sheep to roam adjacent to bighorn boundaries set by Colorado Parks and Wildlife (CPW). 

Effective separation is difficult due to a bighorn behavior called forays, where they form networks and venture outside of their home range in search of others. Domestic sheep can also go astray, but this behavior is the primary reason sheep pathogens are often able to spill over into bighorn habitat. 

BLM wildlife biologist Kathy Brodhead analyzed the effects grazing domestic sheep in the allotments have on bighorns. 

“Forays, for the most part, happen during the fall when we are not grazing domestic sheep,” Brodhead said. “But those bighorns are not tied to that boundary in any way.”

Brodhead said there is not a known way to stop the spread of pathogens once a bighorn herd has been infected. Euthanization of wild sheep that are known or suspected to have close contact with domestic sheep is a management tool considered by CPW, but its effectiveness depends on how quickly the agency can respond.  

When considering the risk of disease transmission, the responsible management option may be to remove that wild bighorn before it potentially moves on to another wild herd, said CPW Area Wildlife Manager Brandon Diamond. 

“Assuming we receive a report of contact, we have to quickly locate the animals,” Diamond said. “It's challenging across our big landscapes, often with limited communication.”

Bighorn ranges span through Gunnison Gorge into the West Elks, Taylor Park and down to Cochatopa and Cebolla Creek. There are nine different herds that are within a 35 kilometer foray distance of these allotments.

Grazing disputes have also surfaced in the Washington Cascades and in Eastern Oregon near Hells Canyon, but Colorado is a hot spot for this issue, said Greg Dyson, WildEarth Guardians’ bighorn sheep expert.  

When asked if there is a solution to this problem Dyson said it’s simple, “don’t graze domestic sheep in bighorn habitat.” 

Over the past 50 years, Rocky Mountain bighorn sheep populations in the project area have fluctuated. The EIS states that populations over the past five years are considered to be at a stable level although pathogen transmission is a rising worry. 

Domestic sheep grazing is part of the BLM’s multiple use mission and is authorized under law. However the federal government isn’t making money by renting public lands to livestock producers, WildEarth Guardians’ Molvar said. 

The grazing fee for 2021 on public lands administered by the BLM is $1.35 per animal unit month (AUM) or the amount of forage needed by an animal for one month. It is a small fraction of private land lease costs, which can reach upwards of $20-25 per AMU.  

“It's really a case where the livestock producers really liked to have this cheap, almost free, livestock grazing made available to them every year,” Molvar said “And they put a lot of political pressure on the agency, through their local county commissioners through their representatives in Congress.” 

The BLM’s proposed decision was released on Aug. 27 and is subject to a 15-day protest period for public comments before a final decision is issued. The final decision is then open for a 30-day appeal period for public comment or for organizations to initiate legal action.   

“A lot of these livestock grazing decisions fly under the radar,” Molvar said. 

Across much of the West livestock operations have rented public lands for so long people accept it and forget that both cattle and domestic sheep are relative newcomers in the American West, only having been here for the last 150 years or so, Molvar said.  

When you add these new mouths to feed onto an ecosystem that already had elk, bighorn sheep, mule deer, pronghorn, Gunnison sage-grouse and hundreds of other species that are all allocating resources amongst themselves, then something has to give, he added.  

“All of these have taken a hit to accommodate this new grazing pressure and all of the physical impacts that go with it,” Molvar said. 

The BLM Gunnison Field Office declined to share contacts for sheep grazing permittees with the Times. The Times reached out to the Colorado Wool Growers Association, an industry group that advocates for sheep operations, but did not receive a response by press time.

(Bella Biondini can be contacted at 970.641.1414 or bella@gunnisontimes.com.)