Conclusion and Takeaway Message
INTRODUCTION
This study’s results illustrate the importance of custodial wildlife management when it comes to the tough task of preventing bighorn-domestic sheep interaction through effective policy. Its findings also verify the conclusions of other wild-domestic sheep interaction policy researchers. Additionally, this study serves as a valuable information resource for natural resource managers who are often charged with both policy formulation/improvement and implementation.
This project’s shortcomings include a limited geographic scope, a dearth of information available for the Aldrich Mountain case study, and an absence of field research. Furthermore, this analysis was bighorn-centric and government agency-centric with little representation of the views of the domestic sheep industry. Moreover, this study focuses almost exclusively on domestic sheep, though domestic goats present a similar disease threat to bighorns. Although all these shortcomings could be addressed with further research, additional research could also be done by geographers adapting the methodology of this thesis to other contentious wildlife-livestock interaction policy issues.
Bighorn management in general, and bighorn-domestic sheep management in particular, involve many stakeholders and the science/policy interface. The wild-domestic sheep issue has gained much attention in recent years and is poised to continue its high profile role in the drama of the American West’s natural resource management controversies. Bighorns need human protection and help for their effective conservation, and complete separation of wild and domestic sheep is one of the best ways to conserve bighorns. Nonetheless, that solution is not always easily implemented in reality.
FINDINGS' RELATIONSHIP WITH MANAGEMENT APPROACHES
Research for this thesis repeatedly verified that bighorns and domestic sheep are not compatible on the same ranges. Other researchers arrived at this conclusion in similar policy/location analysis literature discussed in Chapter II (Monello, Murray, and Cassirer 2001; Clifford et al. 2009; Cahn et al. 2011). This study’s findings tie into, verify, and could improve wildlife management and wild-domestic sheep management approaches. The case studies in this project illustrate that bighorn-domestic sheep interaction policies (both custodial and manipulative) can sometimes be successful with diligence, but success is unpredictable and location-dependent. This determination verifies Schommer’s views discussed in Chapter II. Schommer notes: “Each allotment includes grazing practices specific to the allotment and permittee and each allotment carries its own set of unique circumstances that need to be evaluated. What works in one location may not work in another” (USFS 2010b, 1).
Results of this study also underscore the need for better preventative, custodial management of bighorns. Manipulative management can be expensive and time-consuming, and it may not amount to much if insufficient custodial management results in the elimination of a bighorn herd because of a disease outbreak. Moreover, the findings of this research indicate that the domestic sheep disease threat should be a staple of any bighorn management guidelines. Though lacking in some older publications (NDFG 1978; Wishart 1978), the bighorn-domestic sheep disease issue has become increasingly prominent in the bighorn management literature.
As repeatedly emphasized in Chapters I and II, this study can serve as a valuable information resource that could improve and mature the field of bighorn management. This thesis will be an important tool for biologists, land managers, and policy specialists unfamiliar with the disease issue (e.g., those who experienced geographic transfers or promotions that necessitate awareness of the intricacies of bighorn-domestic sheep interaction management). In their response to a survey questionnaire presented to bighorn managers at the 2nd North American Wild Sheep Conference, Cummings and Stevenson emphasized that Nevada regularly receives federal agency personnel from Washington who are not knowledgeable about important bighorn-related issues (Arthur et al. 1999).
SHORTCOMINGS AND NEED FOR ADDITIONAL RESEARCH
This project only analyzes six case study locations of an estimated 66 known die-off events that occurred from 1990-2010 (Ryder et al. 1992; Miller et al. 1995; Cassirer et al. 1996; Torres, Bleich, and Wehausen 1996; Ward et al. 1997; Aune et al. 1998; Cummings and Stevenson 1998; Arthur et al. 1999; Coggins et al. 2000; Merwin and Brundige 2000; ODFW 2003; Jansen et al. 2007; Rominger and Goldstein 2007; USFS 2007; Buchanan 2008; Byron 2008; George et al. 2008; Malmberg, Nordeen, and Butterfield 2008; NDOW 2008a; Olson et al. 2008; Cassaigne, Medellín, and Guasco 2010; MFWP 2010a; WAFWA 2010a; WAFWA 2010c; Wolfe et al. 2010). It is important to note that due to incomplete information, this estimate is probably low. As such, this study might have yielded more conclusive results if it analyzed more locations, but it is felt that the results are representative of those that would be obtained from a larger study and that they can adequately inform wildlife management policies and managers. Representative, important bighorn habitats were analyzed, but the case study locations did not include hot desert, steep river canyons, or Great Basin rimrock. Attempting to represent these other habitat types could be part of additional case studies or an expanded study.
Furthermore, for years, Hells Canyon (carved by the Snake River and located where Oregon, Idaho, and Washington meet) has been a major focal point of bighorn-domestic sheep disease controversy, and this study only briefly touches on it. Studies focusing on subpopulations of bighorns within Hells Canyon and analyzing related domestic sheep allotments and related management policies and litigation could produce substantive research results that reinforce and expand on the findings of this project. The Payette National Forest borders Hells Canyon, and the flurry of bighorn-domestic sheep policy activity in the Forest was also only briefly addressed in this study and could form the basis for additional policy analysis.
Information concerning several of the case study locations was especially limited or non-existent. For example, not many details were discovered for Aldrich Mountain, particularly regarding possible conflict between the Oregon Department of Fish and Wildlife and the U.S. Forest Service. This project could benefit from further study of the Aldrich Mountain die-off. Additionally, along with secondary research, only phone and e-mail interviews were conducted. On-the-ground research focusing on field office records (e.g., documents concerning range conditions, grazing allotments, domestic sheep and/or bighorn dynamics, etc.) and in-person interviews could yield information with greater quantity and quality.
An especially notable shortcoming of this project is that all individuals interviewed were either wildlife managers or public land managers. The literature that was examined was also skewed toward that originating from wildlife and land management agencies. This thesis is admittedly bighorn-centric, but further fleshing out the views of the domestic sheep industry and sheep operators would provide more balanced and interesting results. The implementation of many interaction policies ultimately depends on the discretion and cooperation of sheep owners and herders. A sequel project using the same general approach as this thesis (case study profiles with policy analysis) but focusing on domestic sheep operators could generate incisive and useful complementary research.
Another shortcoming of this study was that it only focused on domestic sheep when wild-domestic sheep interaction policies also apply to domestic goats, which pose a similar disease threat. In addition to being raised and used for similar purposes as domestic sheep, domestic goats are sometimes used by recreationists as pack animals in high mountain bighorn habitat. That factor could add a new dimension to bighorn-livestock interaction policy analysis. In general, domestic goat-bighorn interaction policies and situations related to disease transmission could provide rich material for additional research, especially because the goat industry has been on the rise in the U.S. According to Professor Solaiman: “In the United States, meat goat production has been gaining popularity in recent years particularly because of a growing population of ethnic and faith-based groups who consume goat meat” (2007, 2).
The methodology of this project—with its regional comparisons, cultural biogeography, and nature conservation themes—could serve as a template for additional geographic studies of controversial natural resources policy issues. This project looks at pastoralism’s detrimental impact on wildlife, which is something geographers have not significantly studied and may wish to investigate in more detail. For example, bison-cattle disease interaction management is another topical, dynamic subject that could be geographically analyzed in the same manner as the bighorn-domestic sheep disease issue.
TAKEAWAY MESSAGE
Lisa K. Harris and William W. Shaw (researchers at The University of Arizona) state: “Mountain sheep management takes place in the arenas of biology, politics, interagency conflicts and cooperation, public opinion, and the public policy development process” (1993, 16). Bighorn-domestic sheep interaction management involves controversy associated with economic and cultural tensions, science denial, litigation, legislative maneuvering, and research and advocacy—all of these are poised to continue. The bighorn-domestic sheep disease issue is destined to gain prominence and media attention in future years as bighorn numbers expand, new findings come to light, and more people become aware of the topic’s importance.
If bighorns and domestic sheep are to coexist in the same areas without disease outbreaks devastating wild sheep, one size-fits-all interaction policies covering the entire American West will not be effective. To quote Colorado Division of Wildlife veterinarian Mark Miller: “I believe segregating bighorn and domestic sheep on native ranges remains the single most effective management tool for preventing pneumonia epidemics in free-ranging bighorn sheep” (USFS 2001, 4). From a strictly ecological context, not allowing domestic sheep and bighorns to share the same ranges at all is the least risky and most effective way to prevent bighorn die-offs caused by domestic sheep.
However, bighorn and domestic sheep stakeholders live in a world where wild-domestic sheep interaction also exists in political and economic contexts. Complete removal of domestic sheep in bighorn ranges will not always be possible or desirable. Bighorn-domestic sheep interaction management policies should involve compromise and prioritization if they are to be successful. This could mean fewer or no bighorns or domestic sheep in certain areas—and fewer futile attempts to maintain coexistence. Wildlife veterinarian Deana L. Clifford et al. aptly share some of these same conclusions in their assessment of wild-domestic sheep disease risk in the Sierra:
"To eliminate all risk of contact and potential disease transmission, domestic sheep cannot be grazed on allotments that overlap with areas utilized by Sierra Nevada bighorn sheep. Where wildlife and domestic animal populations share limited habitat, and there is documented evidence of a substantial disease threat and extinction risk, stakeholders must recognize that the only way to eliminate contact and risk of disease transmission is to give priority to one species or the other. If conservation is the priority, difficult decisions will need to be made to balance trade-offs between economic livelihoods and species conservation" (2009, 2559).
The case of bighorns in the Sierra (Reiterman 2005; USFWS 2007; CDFG 2009) illustrates how the Endangered Species Act (ESA) could be used more often to motivate more effective wild-domestic sheep separation policies. The ESA is powerful, and the act itself (or merely the fear of ESA designation) can trigger increased policy efficacy and more innovative management approaches. Though not all bighorns are endangered, the ESA allows for the listing of special subpopulations: subspecies, distinct population segments (DPSs), and evolutionarily significant units (ESUs) (Nie 2012b). Getting DPS or ESU designation for particularly vulnerable bighorn populations near domestic sheep could result in rapid development of effective policies and maybe even complete removal of domestic sheep.
While complete removal of domestic sheep is a clear way to reduce bighorn health risks, issues of economics and social justice should not be dismissed. Federal agencies should make domestic sheep removal agreeable to livestock producers through reasonable, fair means. Aside from the obvious incentive of direct payment, agencies could implement efforts to perform land swaps with ranchers in regions with checkerboard private/government ownership patterns. Such swaps might compensate sheep ranchers for lost range and better consolidate portions of bighorn habitat in the public domain.
Agencies could also take advantage of the fact that bighorns may often have more economic value in particular areas than domestic sheep. Bighorns are popular enough to have become the state mammal in Nevada and Colorado, and bighorn hunting permits have been auctioned for hundreds of thousands of dollars (BLM 1995b; ODFW 2003). Federal agencies could promote bighorns’ economic value in their efforts to remove domestic sheep. They could also help domestic sheep ranchers transition from grazing to forms of economic activity that involve bighorns. For example, some domestic sheep operators could become outfitter-guides who help hunters and wildlife viewers find bighorns in the backcountry. Though the feasibility of this idea is highly variable based on location, in some instances, it might compensate for producers losing allotments.
Wild sheep biologist Wayne E. Heimer ends his 2002 analysis of the bighorn-domestic sheep disease issue by remarking:
"My recommendation for wildlife biologists would be to leave the bacterial adventures and vaccine development to specialists in those fields, and to concentrate on doing the best we can to humanely separate bighorns from domestics. It’s not sexy, and it’s not new; but it will probably do more for bighorns than the excursions into DNA, diseases, and parasites that have occupied us for the last 50 years" (2002, 164).
Bighorn biologists Raul Valdez and Paul R. Krausman provide a reminder of why bighorn conservation matters:
"Mountain sheep, like all other native fauna and flora, are a part of the structure and heritage of North America. Despite all of the efforts exerted toward their conservation, wild sheep face a precarious future. They are an ecologically fragile species, adapted to limited habitats that are increasingly fragmented. . . . According mountain sheep their rightful share of North America and allowing them to inhabit the wilderness regions they require is a responsibility all Americans must shoulder. It is our moral and ethical obligation never to relent in the struggle to ensure their survival" (1999, 22).
In autumn 1939, Oregon State College graduate Don Moore undertook an assignment for the U.S Biological Survey to seek Oregon’s last bighorns in Hells Canyon. Moore failed to find bighorns or even their tracks. However, he heard at least one story from a local who connected bighorn disappearance with domestic sheep arrival (Hoffman 2007). Though focused on northeast Oregon, in Moore’s report on his investigation, he asked a question that could be applied to much of the American West well into the twenty-first century: “Are mountain sheep . . . of more value to the people of the nation as a whole than is the grazing industry in this area” (Hoffman 2007)?
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