Sunrise light on a grove of tufa towers emerging from the water of Mono Lake with soft green and dusty-red wild grasses in the foreground, Canada geese in the shallow water with reflections of the rocky towers, and desert hills in the distance.

Sierra Nevada bighorn sheep disease risk eliminated

This post was written by Lisa Cutting, 2002-2020 Eastern Sierra Policy Director, 2000-2001 Environmental Resource Coordinator, and 1999 Mono Lake Intern.

Yesterday the Mono County Board of Supervisors voted 3-1 with one recusal not to renew a grazing lease for domestic sheep on Conway and Mattly ranch properties owned by Mono County. The current domestic sheep grazing lease expires in November 2017 so after this grazing season domestic sheep will no longer be grazed in the north Mono Basin.

Photo courtesy of the Sierra Nevada Bighorn Sheep Foundation.

The California Department of Fish & Wildlife and US Fish & Wildlife Service presented extensive scientific evidence that laid out the case for terminating domestic sheep grazing within one mile of endangered Sierra Nevada bighorn sheep habitat because domestic sheep are known to transmit a deadly pneumonia to bighorn sheep. With Sierra bighorn residing in and around Lundy Canyon close to Conway Ranch, the scientists determined the risk of wild sheep contracting pneumonia from domestic sheep was simply too high.

As US Fish & Wildlife Service representative Lee Ann Carranza said, “We have been trying for nearly 20 years to figure out a way to make it work to keep sheep grazing on Conway while trying to recover bighorn sheep without undue risk to the endangered sheep. It is simply not possible. If an easy solution was at hand it would’ve been implemented.” She also said that the wildlife agencies responsible for bighorn sheep recovery have been hesitant to augment the Mt. Warren herd (part of the northern recovery unit), as they have done with other herds, due to the high risk of domestic-bighorn contact. Now that sheep grazing will be terminated after the 2017 season, the wildlife agencies will take more active measures to help recover this herd.

After nearly five hours of presentation and testimony, the Board of Supervisors deliberated and then voted not to renew a grazing lease for Conway Ranch and said specifically that domestic sheep grazing needed to be terminated due to the risk to bighorn sheep.

After many years of debate, this is a momentous step and allows the agencies to move forward with additional bighorn sheep recovery program actions.

Thank you to everyone who wrote letters supporting the bighorn sheep or attended the meeting yesterday and spoke on their behalf. Thank you to the agency representatives who gave such informative and compelling presentations and who are committed to the recovery of this iconic species. And thank you to Mono County Supervisors and staff who gave this issue the time and attention that it so deserved.

If you want to watch part or all of the marathon meeting you can do that here. Agency presentations begin at 2:39; staff presentation on grazing issue and public testimony begins at 4:53; Board deliberation begins at 6:40.


  1. That is good news. It is especially gratifying that the Mono County Supervisors were guided by the evidence before voting on this contentious issue. Good for them!
    Peter Ralston

  2. Congratulations to the Board of Supervisors, the Fish & Wildlife Services, the Mono Lake Committee, and all concerned for this magnificent result.

    We were in Borrego Springs last weekend. When leaving to come home, we saw 9 Bighorn Sheep on the mountain side high above San Diego County Route 22. What a thrill.


  3. Comment continued:

    Preserving those magnificent creatures is truly the Lord’s work. God bless each and every one of you.