Section A
Common Ground on Disease Based Conflicts Between Bighorn Sheep Conservation and Public Land Grazing of Domestic Sheep and Goats
Introduction: Over the last decade a number of efforts have been made to refine our knowledge of diseases, particularly respiratory diseases, that may be infectious between sheep, goats and bighorn sheep; define where, when, why and how these health and disease problems occur; identify and quantify risks; find ways to achieve separation between domestics and wild sheep; and develop guidelines and best management practices that will both protect the health of bighorn sheep and allow grazers to continue in business. The information which follows comes from a wide variety of sources and it is provided in the hope that “the truth shall set you free”, free to quit arguing minor points and obfuscating and free to move on toward working out practical, reasonable and acceptable solutions.
A huge amount of progress has been made in the last few years. A bibliography of existing research and observations has been gathered together, landmark risk assessments have been done, key research finding have been published, and a series of workshops designed to disseminate information, identify key unanswered questions, and build consensus have been held from 2007-2008. Although as of January 1, 2010 we have not come to complete agreement, and litigation has been the result in several cases. We have not solved all our problems, or begun implementing national or regional policies, but we are much closer than we have ever been. We may have more common ground now than ever before.
Common Ground on Bighorn/Domestic Sheep Diseases. What do we agree on ?
Six separate reports or documents (listed below) from the widest possible array of parties and interest groups reach the essentially same conclusion. They form a consensus on what the basic problem is and the first steps to be taken, an emergence of common ground that seems acceptable to essentially all parties. Whether they constitute a single consensus, or essentially a consensus by many similar consensus efforts (meta consensus), or a series of separate regional and/or national consensus dcouments, is debatable. But, these statements from widely divergent groups all recognize the basic problem, when bighorn mix with domestic sheep or goats they often then subsequently suffer catastrophic disease outbreaks, and preventing these interactions is critical……Please examine the following and decide for yourself if we have basic consensus and “common ground” from which we can go forward together.
I. Wyoming State-wide Bighorn/Domestic Sheep Interaction Working Group 9/2004 Report to the Governor from the Wyoming Livestock Board, Wyoming Department of Agriculture and Wyoming Game and Fish Department with participation from Federal agencies and interest groups.
“Bighorn sheep are important to Wyoming and should be protected and enhanced in terms of numbers, health and distribution. Diseases may be interchanged between domestic and bighorn sheep; in Wyoming, Pasteurella spp. - induced pneumonia is the most important. Pasteurellosis in sheep is a very complex issue that needs better understanding by all individuals, agencies and organizations. There is a risk of disease transmission….Zero risk of disease is unattainable but management can reduce risk…”
II. The “Payette Principles” were developed and unanimously agreed upon in 11/2006 in Boise, ID by a group of wildlife and livestock veterinarians and researchers with a wide spectrum of views on domestic/bighorn sheep health issues as the preamble to a scientific review panel report sponsored by the Payette National Forest. The first principle is:
1. a) Scientific observation and field studies demonstrate that “contact” between domestic sheep and bighorn sheep is possible under range conditions. The contact increases risk of subsequent bighorn sheep mortality and reduced recruitment, primarily due to respiratory disease.
b) The complete range of mechanisms/causal agents that lead to epizootic disease events cannot be conclusively proven at this point.
c) Given the previous statements, it is prudent to undertake management to prevent contact between these species.
Mark Drew1, Bill Foreyt2, Ben Gonzales3, Elena Garde4, Dave Jessup3, Kim Keating5, Mike Miller6, Anette Rink7, Sri Srikumanan2, Al Ward8, Glen Weiser8.
1 Idaho Department of Agriculture; 2 Washington State University; 3 California Department of Fish and Game; 4 British Columbia Ministry of Environment, Canada; 5 United States Geologic Survey; 6 Colorado Division of Wildlife; 7 Nevada Department of Agriculture; 8 University of Idaho.
III Wild Sheep Working Group (WSWG) Report and Recommendations of 6/2007 to Western Association of Fish and Wildlife Agencies (WAFWA-23 State and Federal Agencies) adopted by WAFWA 9/2007, subsequently adopted by AFWA – 50 State and all Federal Wildlife Agencies.
This report adopts and includes all of the “Payette Principles” and states:
“Throughout significant portions of their range bighorn sheep suffer from periodic population depression, largely resulting from recurrent respiratory disease epizootics. Over the past 30 years there has been a steadily increasing body of anecdotal and empirical evidence underscoring the potential risk of disease transmission from domestic sheep and goats to wild sheep. The WSWG collectively believes that effective separation (spatial and temporal) between wild sheep and domestic sheep and goats should be a primary management goal of state and provincial agencies responsible for wildlife management.”
IV. Pasteurellosis Transmission Risks between Domestic and Wild Sheep 8/2008 for Congress on Animal Science and Technology (CAST) by M. Miller, M. Bulgin, D. Knowles, reviewed by B. Clay, W. Cook, S. Srikumaran.
“Disease has contributed significantly to the decline of bighorn sheep thoughout much of western North America. Based on evidence from empirical studies and field observations, interactions between wild sheep and domestic sheep increase the probability of mortality and reduced lamb survival in wild sheep populations, primarily due to respiratory disease. Quantifying the risk of interspecies transmission between domestic and wild sheep in a natural setting is problematic. The most practical approaches identified thus far for minimizing risk involve preventing interspecies interactions that could result in respiratory pathogen transmission.”
V. A Review of Disease Related Conflicts Between Domestic Sheep and Goats and Bighorn Sheep 9/2008 by T. Schommer and M. Woolever as a General Technical Report (GTR-209) from the US Forest Service Rocky Mountain Research Center.
“The scientific literature and expert panels support the conclusion that bighorn sheep and domestic sheep/goats should not occupy the same ranges simultaneously or be managed in close proximity to each other if maintenance of a bighorn sheep population is a management objective. The literature is clear regarding the high probability of bighorn dying of pneumonia following contact with domestic sheep. Efforts to identify organisms causing pneumonia in bighorn sheep following contact with domestic sheep have identified many pathogenic bacteria of multiple species, but specific mechanisms/causal agents that lead to epizootic disease events are not completely understood.”
VI. Recommendations on best management practices for domestic sheep grazing
on public land ranges shared with bighorn sheep 10/2009 by USAHA JOINT WORKING GROUP: Committee of Wildlife Diseases & Committee on Sheep and Goats including M. Miller, W. E. Cook, D. Knowles, N. East, R. Lee, C. Palmer, M. Atkinson, A. Rink, C. Wolf and J. Fischer.
“The foregoing best management practices are based on current understanding about the circumstances leading to pasteurellosis epidemics in bighorn sheep after contact with domestic sheep. Improved understanding about this relationship and about controlling respiratory diseases in sheep in general should allow refinement of these practices.”
“As per the group’s charge, the recommendations that were developed focus on practices intended to minimize opportunities for interspecies contact on shared range that could lead to transmission of respiratory pathogens. In some recent pneumonia epidemics in bighorn sheep, the cause has been attributed to endemic respiratory pathogens, and in other epidemics the cause has been attributed to pathogens introduced via interactions with domestic sheep.”
Wild Sheep Respiratory Disease Workshop - On April 25 and 26, 2007 a selected group of veterinary scientists, national and international experts on respiratory diseases of livestock and wildlife were brought together in Davis, CA to review basic concepts, new findings, mechanisms of disease and to work on as yet unsolved questions and problems. The entire meeting was professionally facilitated and recorded and can be found here.
February 2008 Wild and Domestic Sheep Disease Risk and Management Workshop- This third in a series of workshops took place in Salt Lake City, Utah in conjunction with the annual meeting of the Foundation for North American Wild Sheep. Updated February 7th, 2008 with Abstracts and PowerPoint presentations from the workshop.
Part 3:
WAFWA Wild Sheep Management Guildlines- In July of 2007 the Western Association of Fish and Wildlife Agencies (WAFWA) adopted a set of guidelines for management of bighorn/domestic sheep disease conflicts. WAFWA represents the directors and State wildlife conservation agencies of 11 western states and their federal agency counterparts. These guidelines represent a set of collaboratively developed “best management practices” for wildlife and land managers, range land users and grazers and conservation organizations. Comments on this document will be considered when at the February 2008 workshop.
USAHA-BMP's In 2008-2009 committees of the United States Animal Health Association developed recommendations for best management practices for domestic sheep and bighorn sheep by consensus.
Part 4: CAST Document
Sheep Pasteurellosis News Release (PDF) - This report was developed for the Council of Agricultural Science and Technology and represents a consensus on the issue and agreement that contact between domestic sheep and bighorns is a risk factor for disease transmission and that seperation is a reasonable management tool. new!
CAST Commentary: Pasteurellosis Transmission Risks between Domestic and Wild Sheep (PDF)
RESEARCH PAPERS:Pdf’s of the following papers have recently become available and are provided for your interest.The role of Mycoplasmaovipneumonia as one of the perhaps unappreciated causes of pneumonia in wild/domestic sheep is currently a hot area of research and interest:
Payette Principles - These principles arose out of the November 2006 US Forest Service meeting in Boise, ID and were unanimously endorsed by a panel of experts that included both domestic livestock interests and wildlife interests. They may serve as common ground for future discussions and were reviewed and engendered little dissent at the April, 2007 Davis, CA workshop, although a formal to determine if there was consensus was not held.
Payette National Forest Qualitative Risk Assessment - In November of 2006 a panel of experts was brought together in Boise, ID by the US Forest Service to review a qualitative risk assessment done for grazing in and around Hells Canyon. Qualitative risk assessment is a commonly used tool to attempt to determine where risks exist and how they can be mitigated.Although this risk assessment was controversial because representatives of the grazing and the veterinary/animal health communities were not part of the expert team, the panel of experts did not find significant fault with the methods or conclusions.
Sierra NevadaQuantitative risk assessment; Quantitative risk assessment is a relatively new tool for assessing disease risk stemming from contact between bighorn and domestic sheep. It has the advantage of allowing one to vary contact related parameters and determine how changes in grazing and management activities may alter risk. They are more complicated and require more precise data than qualitative risk assessment and the one provided is specific to the Sierra NevadaMountain populations of California.
Clifford et al Recent published article on quantitative risk assessment.
Section E:Historic Literature
Foundational and Historic Literature- A list of 200 references pertinent to pneumonia in wild and domestic animals, pneumoina and other diseases of bighorn sheep, domestic sheep and goats courtesy of Dr. Mark Drew.
Documentation of Wild Sheep Dieoffs Following Contact with Domestics (PDF listings) There has been a good deal of controversy over whether sufficient documentation and/or scientific literature exists to show that bighorn sheep dieoffs often following domestic sheep and goat contact (see “Payette Debate” above).
