Archive | June, 2022

USFWS Silverspot Butterfly Comments


U.S. Fish and Wildlife Service,
Public Comments Processing,
Attn: FWS–R6–ES–2021–0134,
MS: PRB/3W, 5275
Leesburg Pike, Falls Church, VA 22041–3803

RE: Threatened Species Status with Section 4(d) Rule for the Silverspot Butterfly
Docket No. FWS–R6–ES–2021–0134; FF09E21000 FXES1111090FEDR 223

Dear Sirs:

Please accept this correspondence as the vigorous opposition of the above Organizations with regard to the Proposed species status of the Silverspot Butterfly (“The Proposal”).   Prior to addressing the specific concerns, the Organizations have regarding the Proposal, we believe a brief summary of each Organization is needed.  The Colorado Off-Highway Vehicle Coalition (“COHVCO”) is a grassroots advocacy organization of approximately 250,000 registered OHV users in Colorado seeking to represent, assist, educate, and empower all OHV recreationists in the protection and promotion of off-highway motorized recreation throughout Colorado. COHVCO is an environmental organization that advocates and promotes the responsible use and conservation of our public lands and natural resources to preserve their aesthetic and recreational qualities for future generations. The Trail Preservation Alliance (“TPA”) is a largely volunteer organization whose intention is to be a viable partner, working with the United States Forest Service (USFS) and the Bureau of Land Management (BLM) to preserve the sport of trail riding.  The TPA acts as an advocate of the sport and takes the necessary action to ensure that the USFS and BLM allocate to trail riding a fair and equitable percentage of access to public lands. Colorado Snowmobile Association (“CSA”) was founded in 1970 to unite the more than 30,000 winter motorized recreationists across the state to enjoy their passion.  CSA has also become the voice of organized snowmobiling seeking to advance, promote and preserve the sport of snowmobiling through work with Federal and state land management agencies and local, state and federal legislators telling the truth about our sport.  For purposes of these comments, TPA, CSA and COHVCO will be referred to as “the Organizations”. The Organizations have been actively involved in numerous esa listing efforts, such as lynx, grey wolves, wolverine and grouse. We have also actively involved in numerous efforts on species management hosted by groups like the US Fish and Wildlife Service, state wildlife agencies and the Western Governors Association efforts on Species management.  These efforts have included a wide range of participation includes panelists in round table discussions at events, financially supporting Wolverine research in Idaho to funding development and distribution of the 3rd version of Lynx Conservation Assessment and strategy.

We must ask what has changed when compared to previous determinations that the Silverspot butterfly species and various DPS was not the basis for listing. This concern is highlighted by the fact the listing documents undertake a significant discussion about what the proper species classification is for the Silverspot.  The highly ambiguous nature of the listing regarding many issues ranging from: 1. The mere definition and description of the subspecies; 2.  The inclusion and exclusion of many factors such as exclusion of pesticides as a possible impact to the species; and 3. Inclusion of habitat fragmentation as a threat without addressing the wide-ranging nature of habitat fragmentation.  The current proposal clearly identifies that the species population is stable and is expected to remain so for the foreseeable future, which means there is time to more completely understand the species, describe and define the species and then address the challenges it is facing.

The lack of clarity on these basic issues will lead to huge confusion for the public and guidance that lacks clarity in the recovery plan.  There is a significant lack of analysis and highly theoretical nature of analysis of possible recreational impacts on butterflies generally which results in conclusions that are horribly internally conflicting.  The only recreational activity even mentioned in the proposed rule is collecting and this is found to be a minimal threat. The Organizations are intimately familiar with decisions and efforts where one agency explicitly and clearly states recreation is not an issue for the species and there should be no change to management of recreation due to the listing and subsequent efforts by other agencies place significant restrictions on recreation when habitat fragmentation is even mentioned. This is exemplified by Wolverine listing efforts, Mexican Owl listings and far too many others to address.  This type of concern explodes when the listing decision is as unclear and conflicting as the Proposal is.  Establishing a clear foundational structure for any listing is critically necessary to avoid conclusions that lack factual basis, such as the recent management of bumble bees as Fish in California.[1] Proposal is totally premature as basic questions are not addressed and may also lead to conclusions and management that lack any factual basis and undermine public support for species management more generally.

1a. The landscape challenges surrounding insects on the ESA cannot be resolved with poor listing decisions for species.

The Organizations must recognize there is significant ongoing discussions on the ability of the ESA to list insects generally.  These discussions have centered around concerns  such as physical characteristics of insects failing to identify the species, the inability of habitat to be identified with any accuracy or the lack of understanding around the challenges to the species. While there is no uniform path forward identified, the general consensus appears to be that species should not be listed without resolving these challenges, as the management process of the ESA simply does not work for insect and several other species.

Several authors have recommended the following rather novel process, but legally questionable resolution to address insect related issues for ESA purposes:

“In light of FWS’s reluctance to change, the best solution to the problem is an increase in knowledge about insect conservation and the use of surrogate species to protect endangered and threatened species until the necessary knowledge base has been established.”[2]

While this is a novel and we believe unadvisable resolution of this issue, it recognizes there are currently significant unresolved issues with the ESA process for insect management. American Entomological Society echoes these concerns in their position paper addressing the challenges of providing ESA protections as follows:

“ESA advocates the following positions regarding the U.S. Endangered Species Act of 1973: • The decision to protect a species should be made on the basis of current scientific evidence, to inform listing and prioritization schemes. • Insect conservation is critical to healthy ecosystems, but a clear bias toward plants and vertebrates exists in the listing process. The population dynamics, interpretations of species boundaries, taxonomic conventions, and other challenges related to identifying and counting insects should be accounted for when assessing their status. Here, the Endangered Species Act needs improvement.[3]

Many of the pitfalls that are faced when listing insects on the ESA, such as accurate descriptions of physical characteristics of the species are exhibited in this listing. The listing and related rules do a commendable job addressing the significant conflict among researchers on how the species is even defined. This type of foundational concern in a listing is a concern.  The listing also fails to address factors that have heavily impacted other species of butterfly and how these factors were found to be excluded or irrelevant to the current listing.  Pesticides would be an example of this issue.

While we are aware there is concern about the species, this does not create a basis for listing.  Uncertainty does not result in a need for a listing, but rather indicates a need for more research to address the foundational requirements for a meaningful listing analysis. The need for listing is further mitigated by the fact that the species is stable currently and only forecast to decline from climate change.  For the Organizations, the 30kft level discussion on the applicability of the ESA to insects is a major concern and should be addressed by the legislature before listings occur. The Organizations are further concerned that these types of listing are hugely problematic when the protections of the ESA are addressed for the species. Those challenges are addressed subsequently in these comments. The Organizations are very concerned that generally the listing will simply create management problems with little benefit to the species.

1b. Conservation efforts without scientific process and standards do not yield results but only conflict.

The Organizations would like to address the larger scale concerns around the Proposal.  As we noted earlier, the Organizations have been involved in dozens of ESA listings, Conservation Assessments and Strategies and other projects to support a wide range of species. Some of these efforts we have been involved with for more than 30 years. While these efforts have spanned decades, we are not sure how much difference it has made for many species and we are not aware of a single species that has been the target of these efforts that has actually been delisted. Globally recognized wildlife researchers have recently identified this as a significant management challenge for all involved, which they outlined this situation as follows:

“However, problems can arise at the outset from the way these issues are framed. For instance, in the field of human–wildlife conflicts they are often presented as a struggle between animals and people, and the conflict between different human interest groups is ignored (Peterson et al., 2010;Redpath et al., 2013). In reality, most of these conflicts are between conservation interests and other human interests, such as farming, hunting or fishing (Redpath et al., 2015b). Representing these issues as conflicts between farmers and predators is misleading and limits the opportunities for management. To help delineate these two dimensions, Young et al. (2010) distinguished between human–wildlife impacts and human–human conflicts.

The problem of framing is further compounded by the fact that it is often the conservationists who, although not neutral in such settings, are the ones driving the development of management strategies. Clearly, they are likely to be biased in seeking outcomes that benefit conservation, and may not be trusted by the other party or parties….Second, policy-makers often want quick fixes and rapid  conflict resolution. Yet, these conflicts are ubiquitous and persistent. We know of no example where a wildlife conflict is considered to have been resolved. Indeed, there are very few instances where they have been effectively managed in the long term to reduce conflict, although there have been some short-term, local successes.”[4]

The Organizations could not agree with this conclusion any more vigorously.  We simply completely agree with this concern.  This type of a management concern is not addressed by listing species that really cannot be described, based on highly modeled habitat, and scientific analysis that fails to address basic consistency of analysis. For this reason alone, the Organizations must oppose the listing of the species which has been found stable currently and for decades to come.  We just need better analysis.

2a. ESA Listings based on scientific conflict and uncertainty are legally insufficient.

The Organizations are concerned the proposed listing is highly theoretical and provides little on the ground analysis or information to support many of the conclusions that are provided, such as how was the range of the species established as many of the factors identified in the listing in no way correspond to the range asserted in the listing.  This lack of actual information is problematic on many issues, such as the consistency in the application of modeling of factors and how these models relate to the legal requirements for listing a species on the ESA. ESA listing that are based on modeling of possible future impacts are problematic, as evidenced by the 2020 withdraw of the proposed Wolverine listing which was withdrawn based on insufficient modeling of the impacts and challenges.

The Proposal identifies the stability of the population as follows:

“We find that the Silverspot is not currently in danger of extinction because the subspecies is still widespread with multiple populations of various sizes and resiliency spread cross its range, capturing known genetic and ecological variation. Therefore, the subspecies currently has sufficient redundancy and representation to withstand catastrophic events and maintain adaptability to changes.”

The decline of the stable population is only forecast as is clearly identified in the Proposal as follows:

“However, we expect that the stressors, individually and cumulatively, will reduce resiliency, redundancy, and representation within all parts of the range within the foreseeable future in light of future climate change effects.”[5]

This forecasting is concerning as the only change for the Silverspot since last attempt to list is the further division of a species into more subspecies and this has been occurring since the late 1970s. We doubt this type of management future could ever have been predicted at the time of the previous listings.  We are also concerned that in previous listings the primary threat to the species was identified as human disturbance. These challenges are outlined in great detail in the Hammond article[6]  published in 1984 identified in the SSA several times, but at no point is the change in what best available science even addressed.  Candidly the situation presented in the Hammond article presents a far more compelling need for listing and grim forecast for the species. Thankfully this has not occurred but we must question how changes such as this can occur without discussion of the analysis and process that the conclusion has resulted from. Clearly this is an example of why forecasting is problematic in the listing process. Given the huge number of subspecies that are now occupying almost overlapping habitat areas, the Organizations have to question how accurate counts are achieved and habitat is drawn with the challenges in even describing the species currently. While researchers should be commended for their on-going efforts around models of insect species as this is scientifically interesting, this is not the basis for listing species on the ESA as this effort falls well short of the legal requirements of listing.

The Organizations would also express concern around the premise that an ESA listing may be found to be sufficient for further management actions in the face of this type of uncertainty, as this flies in the face of best available science and management process.  Best available science and basic management decision making mandates that in these types of situations, the inaccurate modeling effort that is being relied on as the basis for the management action be returned for further development and refinement to improve accuracy. Inaccurate modeling of issues can have catastrophic unintended consequences when management actions are being taken on the model.  Until basic information on the species can be clearly defined and described, any listing is premature as the lack of science is not science but rather evidence of the need for further work on the issue.

2b. Significant clarity must be provided for the identification of these various subspecies.

We are very concerned that without some way to actually describe and identify the species every butterfly that is seen in possible habitat will be assumed to be Endangered and this will create nothing but conflict and management problems.  As previously mentioned, the Organizations are heavily involved with ESA management of several species and these are species that are easily identified based on their physical characteristics by the public.  Members of the public are able to identify a lynx and separate it from a mountain lion.  Most of the public is able to consistently identify a wolf from a fox or coyote.  Even with these generally recognized species boundaries, we have encountered significant concerns and unintended consequences from listing and management of these species. Many of the public believe that simply seeing a creature in the wild creates the need for management action. These concerns are exponently expanded when the listed species cannot be accurately identified as often the public cannot separate butterflies from moths etc. We want to avoid management decisions being based on the fact the public may have saw a butterfly or a moth or other species that may or may not be listed.

The need for a clear and identifiable description of what is a possibly protected species and what is not is exponently compounded by the fact the subspecies can reproduce with each other and create hybrid species. A review of the SSA reveals almost every color in the rainbow is identified as characteristic of the possible subspecies, and they are all about the average size of a butterfly. The SSA clearly states the butterflies will display orange, yellow, brown, black, white or silver. The SSA continues that hybrid species may introduce even more variation into the physical characteristics of the species. Our concerns are again compounded by the huge numbers of environmental factors that may impact these characteristics in insects, including food sources, time the sun, intensity of the sun, parasites, temperature to name a few.

Extensive books have been written about the need for these type of thresholds in the management of wildlife and the ESA listing process from agency partners that work with the USFWS.[7]  This type of foundational structure is critically necessary to avoid conclusions that lack factual basis, such as the recent management of bumble bees as fish in California. These types of conclusions simply must be avoided, no matter how well intentioned they are, as the erosion of public support for species management that can result from decisions that cannot be factually defended is significant.

Our concerns are compounded by the fact the SSA goes into great detail around the scientific conflict that has recently occurred around what is the proper species designation and how many subspecies there are. Most of these decisions have been made in the last 3-5 years. This type of decision reflects exactly the type of uncertainty we believe still persists it the insect listing arena and simply must be resolved with some level of scientific certainty before listing.  Given the significant conflict around what species this falls into and how many subspecies there actually are, the hybrid issue is very significant and completely overlooked in the SSA.  What is the status of these hybrids as the SSA states they are not part of the species to be listed?   This is a serious concern as without a high-quality description of the species, we are unsure how any management of the species can occur.

2c.  Best available science concludes that management may not be possible if there is intrinsic uncertainty in the process that cannot be identified accurately.

The Organizations are very concerned that the species can’t be described with sufficient accuracy to list the species.  This type of foundational uncertainty for a listing can have major impacts throughout the management process. We are very concerned about these unintended impacts of the listing.  Extensive concern about the proper process to address all forms of uncertainty in the listing process have been expressed by wildlife management experts in their efforts to quantify and manage uncertainty in wildlife management efforts. This concern was recently summarized as follows:

“Unfortunately, ecological systems are enormously variable at just about every scale that we study them (Holling, 1973). This variability has numerous sources and, collectively, they contribute to what may be known as ‘uncertainty’. In recognizing the role of uncertainty, it is important to recognize that this may arise both as an intrinsic property of the system as well as a nuisance through inadequate data or observation. In terms of intrinsic sources, for example, spatial variability results from variations in conditions from place to place (Tilman & Karieva, 1997), while temporal variability similarly results from variations in systems through time (Huston, 1994). On the other hand, the measurements of the system may contain inaccuracies. For instance, observational variance is a consequence of our inability to perfectly measure systems, instead relying on sampling in order to build up a picture of the dynamical properties of the system (Dennis et al., 2006; Freckleton et al.,2006).”[8]

Similar concerns around the uncertainty of research and forecasting processes have been the basis of analysis of decades of research and theory development in the ESA realm. Similar concerns have been expressed as early as the 1980s as follows:

“Complexities of nature, obscurity of many species’ life history, and changing  environmental conditions make it difficult to assess the accuracy of extinction risk models. Proposals to list very small populations with known threats and unequivocal population status are the exception today in the coterminous United States. There are few, if any, of the California condor-like species that are not already listed. Many of the species we evaluate now are wide-ranging, with little information available on their life histories. Some of these species have population trend data suggesting declines, but populations may remain in the tens to hundreds of thousands of individuals.”[9]

The Woods article above identifies three species where identification of the species is challenging and the intrinsic problems this creates for management decision making.  Almost 50 years later, resolving this type of uncertainty remains a challenge. The British Ecological Society recently proposed proposes to manage this type of systemic uncertainty into two large classifications to try and mitigate the impacts of uncertainty in wildlife management.  These two classifications are as follows:

“Broadly speaking, it is useful to distinguish intrinsic uncertainty (analogous to the variance in model parameters in an ecological or statistical model) from knowledge uncertainty (by analogy with the measurement error or lack of data in a model). The reason for making the distinction between these two types of uncertainty is important: one is a property of the system itself, while the other is caused by a lack of understanding or data. The two are interactive, and this is perhaps the greatest challenge to making robust predictions in management. If the management outcomes are uncertain both in terms of intrinsic variability and knowledge then they will be largely unpredictable. In this circumstance, it is necessary to question the recommendations given, as well as to consider whether the approach to prediction is the correct one.”[10]

The Sutherland book then undertakes an extensive discussion of possible ways to address informational uncertainty and create a model that provides predictable results that may support a management decision. Given the description of the challenges being faced in the management of the Silverspot butterfly, the Organizations submit that the inability to accurately describe the species falls into the category of intrinsic uncertainty and may not be resolvable.

The Sutherland book further continues and provides an example of what can happen when these factors are not accurately addressed in management decision making. This example is as follows:

“As an example, in the UK there was a programme for government- hired shooters to exterminate ruddy ducks (Oxyura jamaicensis). During the cull, coot (Fulica atra), black-necked grebe (Podiceps nigricollis), common pochard (Aythya ferina) and common scoter (Melanitta nigra) individuals were also shot (Henderson, 2009). This resulted in part from inadequate communication with shooters (Henderson, 2009), who were not ornithologists and failed to distinguish between species. Consequently, there is a possibility of confusion, with procedures subsequently being developed to ensure that confusion is minimised.” [11]

Other researchers have addressed uncertainty in species management processes, modeling of population trends and listing efforts for easily identifiable and describable species as follows:

“Hence, accurate information on population trends is lacking for most species. These challenges to understanding sustainability of elasmobranch fisheries and using precautionary approaches for their management are compounded further by multi-species fisheries and poor species-specific monitoring (Barker and Schluessel, 2005; Lack and Sant, 2009; Dulvy et al., 2017) …. Recently, there has been increasing awareness of the importance of considering multiple sources of uncertainty in demographic parameter estimation and risk assessment (Simpfendorfer et al., 2011; Corte´s et al., 2015; Jaiteh et al., 2017a). In addition, demographic modelling frameworks quantify the degree of caution that should be exercised for their sustainable management and can have major implications for the conservation of species (Caswell et al., 1998; Corte´s, 2002; Corte´s et al., 2015). The two main sources of uncertainty that can be easily accounted for in a modelling framework are measurement error (or trait error), stemming from uncertainty in the empirical estimation of a life history parameter (Harwood and Stokes, 2003; Quiroz et al., 2010), and coefficient error, which is derived from the uncertainty in the values of the coefficients of a model (e.g., uncertainty around the intercept of a linear model, see Quiroz et al., 2010). While multiple sources of uncertainty can be readily accounted for in stock assessments, this has not happened to the same extent in data-poor situations, particularly in commonly used unstructured models (for a recent example see Jaiteh et al., 2017a).” [12]

The description of species and forecasting of population trends has been a challenge in the listing process since the ESA was adopted.  It is well documented that failures to resolve the basic challenges can cause significant problems with management efforts undertaken subsequently. The Organizations submit that exactly these types of challenges will plague any effort to manage the Silverspot as proposed. The Organizations submit the uncertainty intrinsic in the current proposal is FAR greater than any addressed in these articles.  Without resolution of the intrinsic uncertainty resulting from the inability to describe the species, communication of information will simply be impossible.

This inherent conflict in describing the Silverspot could not be more apparent than is presented in the series of pictures from the SSA.


The ability of the species to be identified as a single species from these pictures is exceptionally limited at best.  What is concerning is we must assume these are the best pictures available for the listing and most pictures will fail to provide anything close to this level of detail and quality.  This would represent the type of intrinsic uncertainty or observational variance uncertainty that is discussed as challenges to listing or management in the Review. This is type of uncertainty is a major problem that must be addressed in any management effort for a species as it is concluded when these types of issues are not able to be resolved the management outcomes will be largely unpredictable.

3a. Without a describable species, how is modeling and management of habitat undertaken?

The inability of the species to be accurately described and classified gives rise to a host of other problems in subsequent species management efforts, such as habitat identification or avoiding unintended management actions taken in the generalized habitat information already provided.  Without a good description how do we not have problems with the 2018 US Supreme Court’s unanimous Weyerhaeuser decision and the sufficiency of the listing and related petition under Rule 424.14.  While the USFWS recently withdrew the proposed definition of habitat required by Weyerhaeuser, this does not mitigate the legal requirements of the Weyerhaeuser decision. These challenges are insurmountable when the species cannot be accurately described or separated from other species that are not proposed for listing.

The Organizations are very concerned that the current documentation is highly theoretical in nature and far from a settled scientific model moving forward. The Proposal relies on some type of model or forecast for almost every aspect of the analysis, compounding risk of inaccuracy significantly.  The use of modeling in the ESA has been an issue that has been the basis of dozens of treatises and texts and is far from a resolved issue.[13] These reviews have consistently identified the need for the scientific community to provide legally sufficient basis for species management. This standard has been summarized as follows:

“Given the importance of maintaining biodiversity for both ethical and practical reasons- foe example to sustain environmental goods and services critical to human welfare (Hooper et al 2005)- it is imperative that the scientific community provide land managers with the knowledge and tools needed to meet their conservation mandate.”[14]

Other researchers have stated this standard in the management as listing of identifiable species, such as the Mexican gray wolf as follows:

“Policy-related uncertainty originated from contrasts in thresholds for acceptable risk and disagreement as to how to define endangered species recovery. Rather than turning to PVA to produce politically acceptable definitions of recovery that appear science-based, agencies should clarify the nexus between science and policy elements in their decision processes. The limitations we identify in endangered-species policy and how PVAs are conducted as part of recovery planning must be addressed if PVAs are to fulfill their potential to increase the odds of successful conservation outcomes.”[15]

These treatises also provide highly detailed discussions on the management of uncertainly in the assumptions and data in the species/habitat modeling process. Listing a species that is stable and only facing long term challenges is simply never recommended. Rather, listing a species based on a lack of information on the species is a failure of basic scientific processes around the modeling of any habitat areas for a species.  In  habitat discussions driven by the ESA, too often processes fail in correcting basic modeling errors, as is mandated by the scientific process for modeling any activity.  Instead, these modeling errors which are not based on scientific process are sought to be normalized in a rushed effort to protect a species.

The Organizations vigorously assert that the problems with modeling the species that cannot be described or scientifically defined accurately are compounded when applications of habitat designation standards are undertaken.  While we are aware the Proposal is not designating critical habitat, it is identifying habitat or range in the SSA which creates a myriad of problems by itself. It has been our experience that even when critical habitat is not identified for a species but habitat range is identified, many will attempt to use the modeled range as critical habitat in planning.  This is a problem. This problem is compounded by the fact that often the lack of critical habitat for a species is an issue that can be litigated for years. This could not be more exemplified than by the recent successful court challenge to the USFWS decision not to designate critical habitat for the Canadian Lynx. This decision comes down more than 20 years after the lynx was originally listed for ESA purposes.  Not designating habitat in the Proposal does not mitigate our concerns but rather compounds them as the last thing the Organizations want to participate in is decades of litigation on a species, we don’t present at threat too.

The challenge of modeling habitat is immense and only expanded when the species cannot be defined. Recent USFWS efforts have highlighted the habitat designation challenges for identifiable species as follows:

“In particular, the proposed definition is written so as to include unoccupied habitat, whereas many of the definitions in the ecological literature that we reviewed did not appear to consider unoccupied areas.”

The concern of the scientific community around management of poorly defined habitat is not minor.  The mandate of applying best available science (“BAS”) is one of the cornerstones of the entire Endangered Species Act and is specifically applicable to the designation of both basic habitat and critical habitat.  It is the Organizations position that best available science should be consistently applied throughout the ESA. A few examples of the BAS requirement would include §4(b)(1)(A) of the ESA which requires agencies to make listing decisions based:

“On the basis of the best scientific and commercial data available…”

Similarly, §4(b)(2) specifically requires managers addressing critical habitat designations and review to:

“Designated critical habitat and made revisions thereto, under subsection (a)(3) on the basis of the best scientific data available…”

Section 7(a)(2) of the Act continues applying this BAS cornerstone of the Act to the consultation process as follows:

“In fulfilling the requirements of this paragraph, each agency shall use the best scientific and commercial data available.”

While the process for modeling of any activity has not been a hot bed of legislative activity, modeling of complex activities and relationships occurs consistently throughout the world on a huge number of issues and has been the basis of extensive scientific and scholarly analysis.  While there are an exhaustive number of models for almost any activity, the Organizations are aware that all modeling guidelines require some basic review of the model to ensure the model is accurately predicting the behavior that is sought to be modeled. While no model is perfect in predicting all behavior, there needs to be some level of correlation between the model and the behavior modeled. If the model does not accurately forecast or provide consistent results, the model is fixed and management action is not taken. A good general summary of the modeling and simulation process is provided by, which provides the following general guidance on modeling of behaviors

“Modelling as a substitute for direct measurement and experimentation. Within modelling and simulation, a model is a task-driven, purposeful simplification and abstraction of a perception of reality, shaped by physical, legal, and cognitive constraints.[12] It is task-driven, because a model is captured with a certain question or task in mind. Simplifications leave all the known and observed entities and their relation out that are not important for the task. Abstraction aggregates information that is important, but not needed in the same detail as the object of interest. Both activities, simplification and abstraction, are done purposefully. However, they are done based on a perception of reality. This perception is already a model in itself, as it comes with a physical constraint. There are also constraints on what we are able to legally observe with our current tools and methods, and cognitive constraints which limit what we are able to explain with our current theories.

Evaluating a model: A model is evaluated first and foremost by its consistency to empirical data; any model inconsistent with reproducible observations must be modified or rejected. One way to modify the model is by restricting the domain over which it is credited with having high validity. A case in point is Newtonian physics, which is highly useful except for the very small, the very fast, and the very massive phenomena of the universe. However, a fit to empirical data alone is not sufficient for a model to be accepted as valid. Other factors important in evaluating a model include:

    • Ability to explain past observations
    • Ability to predict future observations
    • Cost of use, especially in combination with other models
    • Refutability, enabling estimation of the degree of confidence in the model
    • Simplicity, or even aesthetic appeal” [16]

As briefly outlined in the Wikipedia definition, the evaluation and revision of any modeling or simulation of behavior is a critical step in the modeling process and without success at this step the model should be modified or rejected entirely. This double check of the accuracy of the model to predict behavior is a basic review for any model of activity or behavior. While the list of modeling guidelines is overwhelming, recognition of the requirement for a double checking of the accuracy of the model under non statutory situations. For creation of a business model, Entrepreneur magazine recommends the following step in the development of a business model:

“2. Confirm that your product or service solves the problem. Once you have a prototype or alpha version, expose it to real customers to see if you get the same excitement and delight that you feel. Look for feedback on how to make it a better fit. If it doesn’t relieve the pain, or doesn’t work, no business model will save you.”[17]

A similar need to double check that any model is accurately reflecting the behavior sought to be modeled in the development of mathematical models.  This requirement in mathematical modeling efforts is outlined by experts as follows:

“3. Determine how the model could be improved. In order to make your model useful for further applications, you need to consider how it could be improved. Are there any variables that you should have considered? Are there any restrictions that could be lifted? Try to find the best way to improve upon your model before you use it again.[8][18]

Similar to the modeling of business activities and mathematical theory, best available science on the modeling of wildlife habitat also has an exceptionally well-defined process for development of species or habitat models.  This process includes a step to review that the results of the model are corresponding with the actual life activity of the species.  This process of modeling wildlife habitat has been outlined as follows:

“Modeling wildlife habitat over this range of scales requires many assumptions about the relationships between wildlife population metrics and habitat occurrence, quality, and spatial distribution. Standard modeling protocol is to explicitly state all assumptions early in the process; substantiate those assumptions with field data, published information, or expert opinion; hypothesize the relationships among wildlife and their habitat; and use the modeling framework to evaluate sensitivities and produce output. One critical assumption underlying this protocol is that habitat is accurately characterized at ecologically relevant scales to the organism(s) of interest.”[19]

 Other experts have provided the following summary of the wildlife habitat modeling process:

“The Process of model evaluation and validation is a critical step in modeling. However, this evaluation should not focus on how well the model captures “truth” (verification) but how well the model performs for its intended purpose.”[20]

Without exaggeration there are libraries full of scholarly materials addressing the proper methodology for the development of habitat models for wildlife, and these range from discussions at a very general level to the specific process that was used to model habitat for a species. This level of vigor in order to establish a defensible scientific model of habitat is often simply not present in the ESA listing process.

Even when addressing wildlife habitat, best available science clearly identifies the need to ensure modeling of habitat areas is actually reflecting the species and the areas the species depends upon for basic life activities. While best available science clearly requires if a model does not accurately reflect the modeled behavior, this is a basis for review and modification of the model and not moving forward with the recommended actions of the model. If the modeling accuracy cannot be improved to a scientifically defensible level, the modeling effort is stopped at some point. This simply is not how modeling of critical habitat has occurred in our experiences under the ESA process as often the rush to protect the species overwhelms any discussion of revision of models due to poor performance of the model in predicting behavior. The Proposal would be a good example of the relationship of these types of challenges in the management of a possible species. Challenges are insurmountable in these discussions without accurate descriptions of the species and some type of analysis being available that is not forecast.

The Organizations believe a comparison to the facts around the listing of the Gopher frog which was struck down in the recent Weyerhaeuser Supreme Court decision and the current proposal will clarify our concerns about the poor resolution of the management of uncertainty. The gopher frog listing provided the following criteria for habitat which are summarized as small ponds that hold reasonable quality water at least 195 days of the year, a lack of predatory fish; and an open canopy herbaceous forest. [21]  The comically broad nature of these modeling factors is immediately apparent, as under these factors the gopher frog could be living in almost any pond in the country. It should be noted that these factors could be applied to a huge number of OTHER species totally unrelated to the gopher frog as well.  Almost no pond in the country could be excluded with these modeling factors despite the fact the gopher frog has never lived in most of the country.  This is an example of a failed habitat model, which could be corrected with a more detailed discussion of why the area is thought to be suitable. The Proposal falls victim to the same overly broad analysis failure as there is no meaningful description of the species that can clarify what is a Silverspot butterfly and what is not.  Hybridization of the species compounds this failure.

Our recommendation for the Proposal is the same as reached by the Court in Weyerhaeuser, the decision cannot be supported without further analysis.

3b. The inability to define habitat as led to conclusions that simply cannot be factually or legally defended in the Proposal.

This question is more than timely with the recent withdrawal of the habitat definition by the service, the uncertainty of the definition expands risk.  Regardless of the final decision by the Service on the habitat definition, best available science still must be complied with. After reviewing many of the definitions that are provided in scientific research, the Organizations believe that the definition of habitat provided by the researchers is stronger than either that is current provided by the Service.  The Organizations have attached a survey of relevant researchers’ definitions of wildlife habitat that was prepared Elsevier publishing as part of their Science Direct journal.[22]  We have attached a copy of this document to these comments as Exhibit “2”.

While we are aware the listing technically is not designating critical habitat, the listing will impact activities in area identified as range, and the failure to properly define habitat areas has led to conclusions regarding various challenges to the habitat areas.  The Organizations must express serious concerns about the arbitrary decision that habitat fragmentation as a threat to the species while pesticide usage is not.  Best available science outlines the significant overlap of the use of pesticides as a component of habitat fragmentation. Example would be the use of pesticides and its impacts on the species.   Proposed Rule provides:

“In this proposed rule, we will discuss only those factors in detail that could meaningfully impact the status of the subspecies. Habitat loss and fragmentation, human-caused hydrologic alteration, livestock grazing, genetic isolation, exotic plant invasion, climate change, climate events, larval desiccation, and collecting are all factors that influence or could influence the subspecies’ viability. Those risks that are not known to have effects on Silverspot populations, such as disease, predation, prescribed burning or wildfire, and pesticides, are not discussed here but are evaluated in the SSA report.”[23]

Conflict with this allocation of threats and best available science on the impacts of pesticides on insects is immediate.  This research has been summarized as follows:

“There is no doubt that pesticides can be enormously beneficial in both agriculture and  preventive medicine, for example to increase (the quality of) crop yields, to maintain healthy  livestock and to prevent the spread of diseases (Oerke, 2006; Cooper and Dobson, 2007;  Aktar et al., 2009; Benelli and Mehlhorn, 2016; Guedes et al., 2016). However, due care is  needed for their use in an effective manner. Not only do we need to carefully establish the  mode of action of pesticides, but also the effects of pesticides on both their intended targets  and non-target species. It is clear that where innocent bystanders of pesticides find their  natural habitat replaced or reduced by agricultural practices they are doubly affected (Potts et  al., 2016). One such group of insects are Lepidoptera which may comprise good indicator  species for the non-target impacts of pesticides. Our relationship with Lepidoptera is a  complex one. On the one hand they are the focus of considerable conservation efforts, predominantly butterflies (Brereton et al., 2011; Potts et al., 2016), but on the other hand 70% of agricultural pests are Lepidoptera, in particular many moth species and a few butterflies.” [24]

The Braak et al articles then continues its discussion of the significant impacts of pesticides generally in an urban setting as follows:

“Furthermore, we also need to consider the impact of non-675 industrial use of pesticides in gardens, parks and other recreation areas such as golf courses, 676 which are increasingly important in agricultural and urbanized landscapes (Colding and 677 Folke, 2009).”[25]

Similar research on monarch butterflies has expressed significant concerns about the impacts of genetic modifications designed to replace pesticides have on habitat and the species as a whole. These concerns are as follows:

“Habitat loss in the overwintering sites in Mexico and California is well documented (Brower et al. 2002; Ramirez et al. 2006), although no direct empirical link between declining overwintering habitat and monarch numbers exists. In addition, the growing use of glyphosate-tolerant genetically modified crops has reduced larval host plant (milkweed, Asclepias spp) abundances in farm fields  across United States and Canada. Increasing acreage of glyphosate-tolerant corn and soybeans are negatively correlated to monarch numbers, with the area of milkweed in farm fields in the United States declining from an estimated 213,000 to 40,300 ha (Pleasants & Oberhauser 2012).”[26]

The pesticide question is asserted to be resolved for some uses as follows in the listing:

“In S. n. nokomis range there is more haying and grazing than cropland, and as a consequence there may be less application of pesticides on or near colonies than in many parts of the U.S. but the amount and type of pesticide use near S. n. nokomis colonies needs to be studied. We currently have no evidence that mortality of the butterfly, bog violet, or native nectar sources have occurred from pesticide use and are not aware that it has currently reduced the viability of the species.”[27]

The Organizations assert this is problematic decision making process  for any effort.  The problematic decision making continues as activities that support agriculture are identified as threats, such as haying of fields and conversions of habitat for other agricultural activities is identified as a threat to the species as habitat fragmentation. We question how this distinction can be justified with any scientific or factual basis.  This conclusion simply lacks any factual basis whatsoever, and would seem to be made in direct conflict to the conclusion that habitat fragmentation is a priority threat to the species.

We are very concerned that habitat fragmentation is often associated with trail usage and other forms of recreation, as this has occurred with other butterfly species.[28]  The Organizations are unable to identify any research supporting a conclusion that  recreational activity as a threat to the species.[29] Given the arbitrary application of existing research in the manner proposed in the listing, excluding any activity associated with urbanization or fragmentation of the habitat areas will be difficult to impossible. This lack of an established relationship between the challenge and management would be seen as a basis for management, and this is a connection we are unwilling to make.

4. Asserting habitat fragmentation is a primary threat to the species without identifying habitat is factually and legally indefensible.

It is with the above structure of scientific and legal analysis, the Organizations submit that the listing of species that eludes accurate description and relies on habitat/range that is modeled is problematic at best.  This concern extends to the determination that habitat fragmentation is a major threat to the species but no habitat is identified.  This seems to be indefensible as a matter of fact and law as this should never happen. How can you determine habitat is fragmenting without identifying what is habitat?  Identifying what is habitat would be a critical first step in the determination that the habitat is fragmented. The SSA provides the following species range map:[30]

Species Range Map

The SSA identifies the questionable management history of the identification of range and habitat and asserts this problem has been resolved as follows:

“Based on the best available scientific information per recent genetic work, the range of S. n. okomis is now better understood than it has been in over a century (Cong et al. 2019). As stated in section 2.3, the range now excludes the Great Basin and Southwest Utah Mountains area (Population 2), the Uinta Mountains area (Population 3), and the Chuska Mountains area (Population 9) for which inclusion in the S. N. okomis range was previously uncertain (Selby 2007, Figure 3, p.11 and p.14). Genetic mixing between the subspecies appears to occur not far from the known locations of identified subspecies (Cong et al., 2019, p. 21).”[31]

While the Organizations commend the development of greater understanding of the species, this provision does not resolve questions but creates them.  Is the current analysis better than previous? Probably.  Is the current analysis legally sufficient to support a listing?  Definitely not.

The Organizations must raise concern over a foundational conflict in the range map with regard to elevation.  Under the SSA the following parameters for elevational habitat for the species is provided:

“S. n. nokomis is known to occur from roughly 5,200 feet to just over 8,300 feet in elevation (Scott Ellis and Mike Fisher, pers. comm., 2020). However, one observation is from 9,250 feet near Silverton, Colorado (SCAN 2020).”[32]

The application of this standard even generally immediately causes huge problems for the mapping of the range, as large tracts of land in the range area are more that 50% higher in elevation than the upper threshold of the habitat range provided in the listing.  This mapped Range is one of the largest high-altitude areas in the country but this conflict is never even addressed.  This is a foundational problem.

The SSA then proceeds through a HIGHLY sight specific discussion of possible impacts to habitat at 19 different locations ranging in size as small as two acres. A large habitat is 500 acres. Many of these populations are identified has genetically isolated as they are more than 30 miles from other populations.  If they are genetically isolated, how has that occurred? How was it determined that the species range only 30 miles?[33]  What was the range of the population previously? How was it determined the species range from Gypsum, Colorado to Albuquerque, New Mexico, which is a distance of more than 400 miles?   It is again a concern that these site-specific habitat areas are modeled, such as the Montrose/San Juan population, bringing in all the modeling concerns we have identified in other areas of these comments. While we understand species range and species habitat are different standards, we have to question the sheer scale of the difference of these determinations in the listing.  Is habitat fragmentation identified on the entire range or the 19 sites?  These are critical decisions for our interests as there will be impacts to the entire range despite the analysis addressing at most less than 10,000 acres and possibly down to 500 acres based on the assumption the butterfly only travel 30 miles.

Even more problematic is the fact that habitat fragmentation is identified by weighting some factors of habitat fragmentation while specifically excluding other factors often associated with habitat fragmentation. This questionable decision making is outlined in the Summary of proposal for habitat fragmentation as follows:

“We found habitat loss and fragmentation (Factor A), incompatible livestock grazing (Factor A), human caused hydrologic alteration (Factor A), and genetic isolation (Factor E) to be the main drivers of the subspecies’ current condition, with the addition of the effects of climate change (Factor E) influencing future condition. These stressors all contribute to loss of habitat quantity and quality for the Silverspot and for the bog violet, the plant on which Silverspot larvae exclusively feed. These threats can currently occur anywhere in the range of the Silverspot, and future effects of climate change are expected to be ubiquitous throughout the subspecies’ range. The existing regulatory mechanisms (Factor D) do not significantly affect the subspecies or ameliorate these stressors; thus, these stressors continue and are predicted to increase in prevalence in the future.”[34]

Again, the Organizations must question how such conclusions are reached.  We are very concerned that the failure to identify habitat areas, even if they are not provided protection, will lead to massive over application of concerns for the species in management. It has been our experience that often trails are thought to be a concern in this situation and this must be avoided.


The Organizations must express serious concerns about the basic validity of the proposal on many levels, from the inability of the species to be physically described, to the highly theoretical nature of much of the analysis of threats. As we have outlined, many of these issues are inherent in attempts to list or manage an insect species.  Best available science has identified the resolution of the problem is statutory and should not be the basis of listing that are not able to resolve these issues.  We must ask what has changed when compared to previous determinations that the Silverspot butterfly species and various DPS was not basis for listing. This concern is highlighted by the fact the listing documents undertake a significant discussion about what the proper species classification is for the Silverspot.  The current proposal clearly identifies that the species population is stable and is expected to remain so for the foreseeable future, which means there is time to more completely understand the species, describe and define the species and then address the challenges it is facing.

The highly ambiguous nature of the listing regarding many issues ranging from: 1. The mere definition and description of the subspecies; 2.  The inclusion and exclusion of many factors such as exclusion of pesticides as a possible impact to the species; and 3. Inclusion of habitat fragmentation as a threat without addressing the wide-ranging nature of habitat fragmentation. Again, the concept of best available science and the legal requirements of the Endangered Species act require resolution of these issues.  Identification of systemic uncertainty and resolving is the basis of significant discussion and these are challenges that can be managed.  The lack of science on these issues is not best available science but a lack of science.

The lack of clarity on these basic issues will lead to huge confusion for the public and guidance that lacks clarity in the recovery plan.  There is a significant lack of analysis and highly theoretical nature of analysis of possible recreational impacts on butterflies generally which results in conclusions that are horribly internally conflicting.  The only recreational activity even mentioned in the proposed rule is collecting and this is found to be a minimal threat. The Organizations are intimately familiar with decisions and efforts where one agency explicitly and clearly states recreation is not an issue for the species and there should be no change to management of recreation due to the listing and subsequent efforts by other agencies place significant restrictions on recreation. This is exemplified by Wolverine listing efforts, Mexican Owl listings and far too many others to address.  This type of concern explodes when the listing decision is as unclear and conflicting as the Proposal is.  This type of foundational structure is critically necessary to avoid conclusions that lack factual basis, such as the recent management of bumble bees as Fish in California.[35] Proposal is totally premature as basic questions are not addressed and may also lead to conclusions and management that lack any factual basis and undermine public support for species management more generally.

Please feel free to contact Scott Jones, Esq. at 518-281-5810 or via email at or Chad Hixon at 719-221-8329 or via email at if you should wish to discuss these matters further.


Scott Jones, Esq.
Authorized Representative – COHVCO
Executive Director CSA

Chad Hixon
Executive Director – TPA



[1] For a more detailed discussion of what should be a deeply concerning issue please see: Bees are ‘fish’ under Calif. Endangered Species Act – state court | Reuters

[2] See, Lugo; Insect Conservation under the Endangered Species Act; Journal of Environmental Law; Vol. 25:97 (2006) at pg. 97.

[3] See, Entomological Society of America; ESA Position Statement on Threatened and Endangered Insect Species: Protecting insects is vitally important to the United States.  A full copy of this document is available here: ESA-Position-Statement-on-Threatened-and-Endangered-Insect-Species.pdf (

[4] See, Young, J., Mitchell, C., & Redpath, S. (2020). Approaches to conflict management and brokering between groups. In W. Sutherland, P. Brotherton, Z. Davies, N. Ockendon, N. Pettorelli, & J. Vickery (Eds.), Conservation Research, Policy and Practice (Ecological Reviews, pp. 230-240). Cambridge: Cambridge University Press. doi:10.1017/9781108638210.014 at pgs. 231-233.(emphasis added)

[5] See, US Fish and Wildlife Service; Endangered and Threatened Wildlife and Plants; Threatened Species Status With Section 4(d) Rule for the Silverspot Butterfly; Federal Register; Vol. 87, No. 86; May 4, 2022 at pg.26330.

[6] See, Hammond, P.C. and D.V. McCorkle. 1983(84). The decline and extinction of Speyeria populations resulting from human environmental disturbances (Nymphalidae: Argynninae). Journal of Research on the Lepidoptera 22:217-224.

[7] See, Nichols et al; Thresholds for conservation and management: structured decision making as a conceptual framework; Patuxent Wildlife Research Center; US Geological Service; 2014

[8] See, Freckleton, R. (2020). Conservation decisions in the face of uncertainty. In W. Sutherland, P. Brotherton, Z. Davies, N. Ockendon, N. Pettorelli, & J. Vickery (Eds.), Conservation Research, Policy and Practice (Ecological Reviews, pp. 183-195). Cambridge: Cambridge University Press. doi:10.1017/9781108638210.011 at pg. 183.  A complete copy of chapter 11 of this review is included with these comments for your convenience as Exhibit “1”. (Hereinafter referred to as the “Sutherland Book” for purposes of these comments.

[9] See, Woods et al; Uncertainty and the Endangered Species Act: Indiana Law Journal volume 83:529 at pg. 531.

[10] See, Sutherland at pg. 185.

[11] Supra note 10.

[12] See, Pardo, S., Cooper, A. B., Reynolds, J. D., et al. 2018. Quantifying the known unknowns: estimating maximum intrinsic rate of population increase in the face of uncertainty. ICES Journal of Marine Science, 75, 953–963.

[13] See, Millspaugh et al: Models for planning wildlife conservation in Large Landscapes; Elsiver Press 2009 at pg. 51.

[14] See, Millspaugh et al; Note #10 at pg. 51.

[15] See, Carroll et al; Biological and Sociopolitical Sources of Uncertainty in Population Viability Analysis for Endangered Species Recovery Planning; Scientific Reports; July 12, 2019

[16] See,; definition of scientific modeling @ accessed September 1, 2020

[17] See, Zwilling, Martin: 7 Steps for Establishing the Right Business Model; January 30, 2015.

[18] See,

[19] See, Orloff & Strong; Models for planning wildlife conservation in large landscapes; 2009

[20] See, Millspaugh et al; Models for Planning Wildlife Conservation in Large Landscapes, Elsiver Publishing 2009 at pg. 5. Internal citations omitted

[21] See, US Fish and Wildlife Service; Proposed Rules; Endangered and Threatened Plants and Wildlife; Designation of critical habitat for the Mississippi Gopher Frog; Federal Register; Vol. 75, No. 106 pg. 31387; Thursday, June 3, 2010 at pg. 31404.

[22] A copy of this review is available here:

[23]See, US Fish and Wildlife Service; Endangered and Threatened Wildlife and Plants; Threatened Species Status With Section 4(d) Rule for the Silverspot Butterfly; Federal Register; Vol. 87, No. 86; May 4, 2022 at pg. 26324

[24] See, Nora Braak, Rebecca Neve, Andrew K. Jones, Melanie Gibbs, Casper J. Breuker;  The effects of insecticides on butterflies – A review; Environmental Pollution, Volume 242, Part A, 2018, Pages 507-518,

[25] See, Braak note 21 at pg. 515.

[26] See, Braak et al; note 22 at pg.

[27] See, SSA at pg. 29.

[28] See, Callippe silverspot butterfly – Wikipedia

[29] The Organizations are aware of limited highly theoretical research that indicates the issue needs more research. Given the inconclusive nature of the efforts it is not discussed here.

[30] See, SSA at pg. 12.

[31] See, SSA at pg. 12.

[32] See, SSA at pg. 18.

[33] For a detailed discussion of the uncertainty inherent in these processes please see: Schultz et al; Does movement behaviour predict population densities? A test with 25 butterfly species; Journal of Animal Ecology 2017, 86, 384–393

[34] See, US Fish and Wildlife Service; Endangered and Threatened Wildlife and Plants; Threatened Species Status With Section 4(d) Rule for the Silverspot Butterfly; Federal Register; Vol. 87, No. 86; May 4, 2022 at pg.26330

[35] See, Bees are ‘fish’ under Calif. Endangered Species Act – state court | Reuters

Continue Reading

Keep Routt Wild – Halt the RNF Rainbow Family Gathering

U.S.D.A. Forest Service
Rocky Mountain Region
Attn: Frank Beum, Regional Forester
1617 Cole Blvd
Lakewood, CO 80401

Rainbow Family Letter

Dear Mr. Beum:

The Trails Preservation Alliance (TPA) calls on the U.S. Forest Service, Colorado Parks and Wildlife and Routt County to stop the Rainbow Family gathering planned on national forest lands in Adams Park this July 1-7.  As many as 30,000 could gather in Routt County for this unauthorized and unpermitted activity in the midst of elk calving and critical wildlife and riparian habitat.  The TPA is a volunteer organization created to be a viable partner to public lands managers, working with the United States Forest Service (USFS) and the Bureau of Land Management (BLM) to preserve multiple-use recreation.

The Forest Service has acknowledged that large group gatherings have significant adverse impacts on forest resources and public health and safety. These include the spread of disease, pollution and trash, soil compaction and damage to archaeological sites, riparian areas and wildlife.  Species listed under the Endangered Species Act such as the gray wolf and Canada lynx could also be adversely affected by the hordes.  At a prior gathering near Paonia in 1992, over 15,000 people with some 4,500 dogs parked over 4,000 vehicles on meadows within the national forest.  Imagine how this works with a “leave no trace philosophy.”   There are no public restrooms or porta potties at these gatherings.

As a steward of the National Forests, the Forest Service has a duty to minimize resource impacts.  This gathering runs afoul of the forest plan and surely violates state and local public health laws and regulations for (a) The sufficiency of sanitation facilities; (b) The sufficiency of waste-disposal facilities; (c) The availability of sufficient potable drinking water; (d) The risk of disease from the physical characteristics of the proposed site or natural conditions associated with the proposed site; and (e) The risk of contamination of critical water supplies.  As prior gatherings have shown, it also poses a very real danger to public safety.

As a result, TPA has encouraged its members and the public to speak out against this environmental catastrophe and to sign and support the petition of Keep Routt Wild to prevent it:  Petition · Halt the Routt National Forest Rainbow Family Gathering Now ·

The TPA ardently supports multiple uses of public lands including motorized access to roads and trails.  In fact, Colorado’s off-highway vehicle fees are the primary funding source for trails maintenance projects that benefit all users–motorized and non-motorized alike.  TPA associates are obligated to follow the ever-complex and restrictive myriad of federal laws and regulations governing their recreation and access to national forest and Bureau of Land Management (BLM) lands.  It is unwise, unfair and unlawful to hold the vast majority of the recreating public to different standards.


Chad Hixon
Executive Director
Trails Preservation Alliance

The Hon. John Hickenlooper
The Hon. Michael Bennett
The Hon. Lauren Boebert
Dan Gibbs, Director, Colorado Dept. of Nat. Resources
Heather Dugan, Acting Director, Colorado Parks and Wildlife
Routt County Board of Commissioners
Bill Jackson, U.S. Forest Service, Rocky Mountain Region
Jason Robertson, U.S. Forest Service, Rocky Mountain Region
Russ Bacon, Medicine Bow Routt National Forest Supervisor
Michael Woodbridge, Hahn Peaks Bears Ears District Ranger
Mary Bedwell, Medicine Bow Public Affairs

Continue Reading

Moab Camping Management


Moab Camping Management & Wildlife Report – RWR, TPA, CORE & COHVCO
Labyrinth Rims Camping Proposal – ORBA, UFWDA & One Voice
Utah Rims Camping Proposal – ORBA, UFWDA & One Voice


Bureau of Land Management
Moab Field Office
Attention:Camping Proposals
82 East Dogwood
Moab, UT 84532

Managing Camping within the Two Rivers SRMA (DOI-BLM-UT-Y010-2021-0096)
Managing Camping within the Utah Rims SRMA (DOI-BLM-UT-Y010-2021-0095-EA)
Managing Camping within the Labyrinth Rims/Gemini Bridges SRMA (DOI-BLM-UT-Y010-2021-0094-EA)

Dear BLM Planning Team:

Please accept this correspondence from the above organizations as our official comments regarding the Two Rivers, Utah Rims, and Labyrinth Rims/Gemini Bridges camping proposals. Most campsites in the Two Rivers planning area are accessed by river, but some are accessed by motor vehicle, and this river-canyon setting provides some of the highest-quality camping available to motorized recreationists. The Utah Rims SRMA and the area southwest of there to Cisco provide a high concentration of motorized trails (especially singletrack) and convenient-yet-scenic campsites. The Labyrinth Rims / Gemini Bridges SRMA, including the north extension to Green River, contains many premiere motorized trails and campsites. Although we recognize the need to more actively manage camping in these areas, the process warrants more public participation and guidance to ensure that a range of quality camping opportunities remain plentiful.

1. Background of Our Organizations

In our comments, the “Organizations” will refer to the following four groups:

Colorado Off Road Enterprise (CORE) is a motorized action group based out of Buena Vista Colorado whose mission is to keep trails open for all users to enjoy. CORE achieves this through trail adoptions, trail maintenance projects, education, stewardship, outreach, and collaborative efforts.

The Colorado Off-Highway Vehicle Coalition (COHVCO) is a grassroots advocacy organization of approximately 2,500 members seeking to represent, assist, educate, and empower all OHV recreationists in the protection and promotion of off-highway motorized recreation throughout Colorado. COHVCO is an environmental organization that advocates and promotes the responsible use and conservation of our public lands and natural resources to preserve their aesthetic and recreational qualities for future generations.

Ride with Respect (RwR) was founded in 2002 to conserve shared-use trails and their surroundings. Since then, over 750 individuals have contributed money or volunteered time to the organization. Primarily in the Moab Field Office, RwR has educated visitors and performed over twenty-thousand hours of high-quality trail work on public lands. RwR has also participated greatly in the Moab Resource Management Plan 2008 revision and subsequent amendments.

The Trails Preservation Alliance (TPA) is an advocacy organization created to be a viable partner to public lands managers, working with the United States Forest Service (USFS) and the Bureau of Land Management (BLM) to preserve the sport of motorized trail riding and multiple use recreation. The TPA acts as an advocate for the sport and takes necessary action to ensure that the USFS and BLM allocate a fair and equitable percentage of public lands to diverse multiple-use recreation opportunities.

2. Introduction

We appreciate the BLM’s Moab Field Office (MFO) for taking the initiative to plan for dispersed camping However, we strongly urge the BLM to further analyze camping use, propose specific sites, and solicit more public input before limiting dispersed camping to designated sites. The size of these planning areas1, effects on neighboring areas (BLM, other public lands, SITLA, and private property), and need for a greater range of alternatives call for a complete plan, whether in the form of a more robust Environmental Assessment (EA) or an Environmental Impact Statement (EIS).

In addition the Draft EAs are presented as camping plans, however, they include proposed restrictions that make them travel management plans (TMPs) and wilderness-characteristics preservation plans. Even if the camping plans close only those routes that were not designated open to begin with, those routes were never analyzed for designation in the 2008 RMP by virtue of their short length, making these camping plans the first opportunity to analyze them and provide for public comment. The camping plans need to state explicitly in the title, introduction, and body of each document that the scope encompasses all three of these planning goals.

That said, we support the other three proposals (requiring a portable toilet, fire pan, and bringing one’s own firewood instead of cutting/gathering), and suggest establishing those supplementary rules without delay2. In fact, the supplementary rules could apply to a larger geographic area3. However, we take issue with many other aspects of the Draft EA’s lone action alternative, and call upon the BLM to widen and deepen its analysis. In the interim, the Organizations and others can assist in education and enforcement to deter driving or even parking outside of truly barren surfaces, whether for camping or other purposes.

3. Benefits of Designating Campsites

The MFO’s 2008 RMP attempts to limit vehicle-based camping simply by requiring vehicles to stay on routes designated open by the TMP. Unsustainable results may stem from several problems, including that:

  1. The BLM and its partners have not widely communicated this TMP restriction in the context of camping,
  2. Many visitors are accustomed to adjacent field offices and USFS districts allowing vehicles to park anywhere within a certain corridor of designated routes for the purpose of camping,
  3. The TMP generally has overlooked routes like camping spurs that are under a hundred-yards long so, in lieu of designated spurs, the camping ethic has been to park on any existing spur,
  4. New spurs created by those who assumed they could park within a corridor are then further established by those who are merely trying to follow existing spurs,
  5. Non-vehicle aspects of camping such as tents and kitchen areas have created barren ground that essentially extends the existing spur, and
  6. Camping spurs have been inadvertently followed by motorized recreationists who are just trying to stay on the designated route, which sometimes leads to further spur proliferation.

All of these problems would be solved simply by designating the camp spurs and roughly defining the boundaries of where vehicles can park (and where campers can set up a tent, kitchen area, etc.), so we support limiting dispersed camping to designated sites.

4. Meaningful Public Involvement

A complete plan should include full transparency and input from the range of recreationists rather than token outreach and administrative decree. The Draft EAs state “Following the establishment of Supplementary Rules, campsites would be chosen for designation following an interdisciplinary team process. Existing dispersed campsites would first be inventoried.” We take issue with relying solely on an interdisciplinary team process without the public input necessary to ensure that all stakeholder perspectives are represented as required. Under “Public Involvement,” the Draft EAs state:

“During preparation of this EA, the public was notified of the project by posting on the BLM’s ePlanning website on August 9, 2021. The BLM received an email from one member of the public as a result of this posting who expressed his concern and asked for answers to some questions, which were supplied via email. The BLM also received a telephone call in support of the Proposed Action.”

One email and one phone call from members of the public, during a period of peak summer travel, hardly constitutes a cross-section of public opinion.

Further, we have specific concerns about the proposed interdisciplinary team process, as demonstrated by a number of unsupported statements in the Draft EAs regarding visitor use, wildlife and other resource impacts. One of the most disconcerting aspects of the Draft EAs is their highly speculative assessment of threats to wildlife, that in effect, elevates hypothetical threats from recreational use to the level of worst-case scenarios that require new restrictions. A full public process would ensure that unsupported statements are vetted and either strengthened or rejected to reach the best decision.

5. Supporting Data

The Draft EAs rely upon surmise and opinions, rather than data, to justify a number of proposed actions, stating:

“…the MFO hosts approximately 3 million visitors per year and a substantial, but unknown number, of these visitors wish to camp. Visitation to the Moab BLM has increased over the last ten years, and dispersed camping pressures have increased commensurately as have the resource impacts, particularly in the last five years.”

However, the “3 million” figure likely refers to visits rather than visitors. Since the same individual may make many visits to the MFO in a given year, the number of visitors is likely a fraction of 3 million. Behind its numbers, the Draft EAs present no data and quantitative analysis to support the proposed action of restricting camping and public access to 164,921 acres of combined planning area. More specifically, they don’t provide evidence of:

  1. An increase of dispersed camping in the planning areas (expressed as the annual percentage increase in camping nights or sites),
  2. Locations where this increase in dispersed camping has occurred, and
  3. Quantified impacts to any “resources such as soils, floodplains/wetlands, vegetative resources, wildlife habitat, cultural resources, paleontological resources, recreation opportunities, and scenic values.”

Without this data, especially without a basic inventory of camping sites and their use in the first place, the BLM is basing its proposed action upon surmise and opinion. Therefore, the BLM is putting the “cart before the horse” in proposing these Draft EAs without clearly documenting need. A complete plan should inventory in detail the campsites, resource conflict areas, and other necessary data to support a range of alternatives and measured analysis.

6. Specificity of Campsites

To justify the need for camping restrictions and solicit meaningful public input, the BLM’s proposal should show a thorough inventory of the existing campsites and a proposal of whether each one would be designated open or closed. The MFO may have previously designated campsites without this public review, but it was for smaller planning areas with much fewer existing campsites.

The Draft EAs state “The exact number of dispersed campsites within the SRMA is not known with certainty, but observation shows that dispersed camping has increased over the years.” Yet they present no data to show that dispersed camping has increased, where it has increased, and where it has increased in sites that would represent a demonstrable threat to the continued existence of any of the species mentioned in the plans. Absent an inventory of dispersed campsites and their presumed overlap with resources, including wildlife resources, the Draft EAs are founded upon speculation.

Such an analysis would be easily accomplished with a combination of publicly available satellite imagery in combination with field surveys to validate results. Changes in usage over time in campsites may be quantified by comparing historical vs. recent satellite imagery, either manually or with change-detection software. The degree of use can be estimated based on ease of access (i.e. distance from road/trailhead, size of disturbed area, presence of firepits, and other variables). Overlapping existing resource layers with a map of dispersed campsites would be a straightforward GIS exercise that would provide a transparent and quantitative basis for proposed actions.

Other BLM field offices have allowed the public to comment on campsite inventories and designations of specific sites that were dispersed and free of any user fees. We understand that future proposals to collect fees (whether for campgrounds or dispersed sites) would trigger additional planning, but site-specific public input is warranted now, as well-over a hundred sites may be designated open or closed. Granted, some of the BLM’s existing parameters will close sites with little debate, but other sites are more complex. The MFO may have done a good job previously designating campsites on a smaller scale, but when it comes to assessing well-over a hundred sites, the public would provide valuable insight. Assessing the current conditions and describing the proposed actions in order to analyze the impacts are not only fundamental tenets of NEPA, they also yield a smarter plan. Plus they garner more buy-in, which could be particularly helpful when blocking off campsites in remote areas.

7. Providing for the Projected Use

If current use levels are unsustainable, that’s only because the current camping rules and lack of communication have been a poor fit for high use levels in this high-desert setting. However, merely by designating campsites and defining their boundaries, the planning areas could easily handle current use levels and in fact some projected growth. The proposal should aim to designate enough campsites to accommodate this growth, as it will ensure the availability of sites, thus increasing compliance.

8. Diversity of Campsites

The proposal should identify different kinds of camping to ensure that campsites are designated to provide a range of opportunities. Some camping is focused on convenience or socialization, and can be satisfied by almost any site that’s near a main road. Other camping is more focused on recreational activities, so it should be located near the recreational destination, plus some scenery and probably ample room for an RV or group of vehicles. Yet other camping is more focused on the setting, so it should view the best scenery, and sites should be more spread out for solitude. Even when it comes to activity-focused camping, providing significant space between sites can prevent conflict between campers by reducing impacts like dust, sound, and lights.

9. Coordination with Developed Campgrounds

The planning areas encompass many developed campgrounds, and several more have been approved for development. This proposal should specify and invite public comment on the approximate buffer distance between developed campgrounds and dispersed campsites. Further it should specify and invite public comment on the locations of potential campgrounds so that future development can be considered when designated dispersed campsites.

10. Coordination with Trails

We appreciate the proposal’s aim to avoid designating campsites in a way that would negatively impact recreational trails, specifically that “Limiting dispersed camping to designated sites would allow the BLM to place campsites in locations that would not cause deleterious impacts to the recreational experience of those attempting to enjoy their public lands. For instance, designated campsites would not be placed within view of popular biking/motorcycle trails…” Indeed, designating sites adjacent to trails can lead to social trails and other management headaches, plus potential conflicts for both the campers and the trail users. In some cases, even though the trail predated the campsite, it may be best to relocate the trail. For example, campsites have encroached Overlook Loop (motorized singletrack along the rim of Westwater Mesa in Utah Rims SRMA), but those sites could be designated open by relocating those segments of Overlook Loop down below the rim. The rim is gentle enough for the trail to dip below it and, even if it lowers the scenic quality of the trail, other segments of the trail will remain quite scenic. One way or the other, providing distance between campsites and motorized routes will enable the sites and routes to be enjoyed fully without having to resort to the placement of constraints upon either one.

11. Affordable Housing

The increasing cost of housing, especially for tourism employees, has become a major issue for communities like Moab. More housing options can be provided on private and SITLA properties in Spanish Valley, so it’s not the BLM’s responsibility to solve this problem. However it is the BLM’s responsibility to avoid inadvertently making private-lands housing more expensive by making public-lands camping less available. It’s the BLM’s responsibility to accommodate camping, from the most primitive sites to developed ones with toilets and shade structures. Otherwise off-grid camping would be displaced to private lands, competing with other uses of private land, further increasing the cost of housing. This may not be the case in regions where public lands are scarce and private lands are plentiful but, in the MFO, BLM campsites should remain in the hundreds.

12. Economic Impacts

The proposal should analyze economic impacts to the region. As the campsites become more organized, the activity may become less burdensome to local services. Campers often bring significant revenue to nearby towns as they resupply and sometimes even visit restaurants, entertainment venues, etc.

13. Extent of Planning Areas

If the MFO will invite public review of campsite inventories and designations of specific sites, then the boundaries for two of the planning areas should be expanded to encompass the full area of comparable terrain that is desirable for camping. Specifically extend the Labyrinth Rims/Gemini Bridges planning area from Tenmile Point Road north to the outskirts of Green River, with the east boundary following the Blue Hills. Likewise extend the Utah Rims planning area from the Westwater Put-In Road southwest to the Cisco Boat-Launch Road, with the north boundary following the highways. These boundaries will exclude the relatively-barren shale soils where camping is less common and less concerning in regard to natural and cultural resources. These boundaries will include the more rugged and colorful formations where camping is more common and comparable to the current planning areas. They will include motorized

singletrack like Mel’s Loop and the Dubinky trail system surrounding White Wash, plus Crystal Geyser 4WD trail, which could benefit from the proactive planning of dispersed campsites.

14. Extent of Restrictions for Wildlife

The Organizations welcome camping restrictions that are necessary to maintain healthy populations of wildlife. However we are unconvinced that the extent of proposed restrictions is warranted, resulting in the closure of many well-established and high-quality campsites unnecessarily. Upon careful review of the Draft EAs, the Organizations developed a wildlife report (below) to refine your guidelines, ensuring both sufficient habitat and camping opportunities where compatible.

15. Additional Comments to Consider

We generally support the detailed comments from our partners at ORBA and the other national OHV groups, so we’re submitting them (enclosed) as part of our own comments, and hope you will carefully consider them to improve your proposal.

16. Conclusion

NEPA requires analysis of the affected environment and impacts to the affected environment, including impacts to the human environment. Such analysis of a proposal to limit camping across a large and popular area is simply impossible without identifying the sites to which camping would be limited. Consequently the Draft EAs fail to account for the negative impacts that concentrating use would cause on camping in the designated sites and reducing use would cause on surrounding areas. Such impacts can be mitigated, but only if the proposal first identifies the campsites and a range of alternatives, as required by NEPA.

In the three planning areas, it would be appropriate to limit camping to designated sites so long as the BLM provides significantly more analysis and opportunities for public comment. The additional work will be worthwhile to designate campsites open or closed through a thorough process. In the meantime, negative impacts from camping can be greatly reduced by advancing the other three proposals (requiring a portable toilet, fire pan, and bringing one’s own firewood), plus more widespread education that vehicles may not park off-trail in order to camp.


Clif Koontz Executive Director Ride with Respect

Chad Hixon Executive Director Trails Preservation Alliance

Marcus Trusty President/Founder Colorado Off Road Enterprise

Scott Jones, Esq. Authorized Representative Colorado Off-Highway Vehicle Coalition

1 The Labyrinth Rims/Gemini Bridges planning area has 120,037 acres of BLM land and 19,000 acres of SITLA property, plus Canyonlands National Park immediately south. Adding Utah Rims/Sunshine Wall (16,704 acre) and Two Rivers (9,180 acres) totals 164,921 acres (258 square miles), which comprises about 9% of the 1.8 million acres managed by the MFO and contains many of the most prized motorized trails in the region.

2 Requiring a portable toilet calls for working with partners to encourage the use of preferred equipment and best practices. The BLM and partners should also provide disposal facilities to avoid improper disposal or placing the burden on local businesses, parks, etc..

3 Wood collection should still be accommodated where appropriate, such as in the pine forests found at higher elevation.

Bureau of Land Management Moab Field Office Attention: Camping Proposals 82 East Dogwood Moab, UT 84532

RE: Managing Camping within the Two Rivers SRMA (DOI-BLM-UT-Y010-2021-0096) Managing Camping within the Utah Rims SRMA (DOI-BLM-UT-Y010-2021-0095-EA) Managing Camping within the Labyrinth Rims/Gemini Bridges SRMA (DOI-BLM-UT-Y010-2021-0094-EA)

Wildlife Report

In this report, the “Organizations” will refer to the Trails Preservation Alliance (TPA), Ride with Respect (RwR), Colorado Off-Highway Vehicle Coalition (COHVCO), and Colorado Off Road Enterprise (CORE).

A. General Concerns

1. Buffer Distances between campsites or travel routes and “sensitive species” are proposed without a sound scientific basis. 

The proposed, one-size-fits all buffers and restrictions are without a sound scientific basis. In justification of buffers and restrictions, the Draft Environmental Assessments (EAs) presume worst-case scenarios of what “may,” “could,” or “possibly” happen to the species in question, and thus a heavy-handed approach appears to be needed. In our view, this appears to be contrary to the scientific integrity guidelines, multiple-use mandate of the BLM, and the Information Quality Act.

From our discussions with subject matter experts, it also appears that some of the “science” cited in support of the impacts in the EAs are not as conclusive as they may appear to be. An expert examination of some of the most influential papers cited in the EAs reveals than some of the conclusions and management recommendations are regrettably based upon surmise and opinion, omissions and misrepresentations, examples drawn from species on other continents, and in one case, simulation modeling that is so bold as to make impact predictions 100 years into the future. (A review of the primary issues with key scientific papers cited in the EAs, especially on bighorn sheep, may be found below). The EAs also cite review papers that summarize the opinions of previous authors rather than actual results based upon data. And finally, some of the study findings appear to be simply taken out of context by the authors of the EAs. Because we understand the difficulty the BLM has working under deadlines with limited staff resources to digest complex, technical subject matter, we are happy to work with them to assist in developing scientifically defensible guidelines for protecting wildlife and other resources.

2. Accurate and Transparent Data is required for mapping the potential for human-wildlife interactions for different species. 

We are concerned that the point/line/polygon data layers used in BLM’s GIS analyses will be approximations of potential habitat rather than verifiable data on species occurrence(s). We are further

concerned that polygon layers could weight all habitat or nesting sites equally, regardless of when use was last documented. In other words, we have observed a tendency in some GIS analyses to extend polygons to capture and weigh all historical locations regardless of how many years ago they were made and how rarely the area is used (see Turner et al. 2004 and 2006 for examples specific to bighorn sheep). Therefore, we specifically request that the BLM utilize a transparent approach and verifiable location data in its GIS analyses so that validation by independent experts and qualified members of the public would be possible. Additionally, we propose that actual location data be plotted to delineate habitat rather than GIS-modeled potential habitat, to determine overlap with bighorn sheep, sensitive plant species, and/or raptor nesting locations.

We strongly discourage the use of arbitrary buffers, kernel functions plotted around location data from individuals (i.e. no 50, 90, or 95% kernels as these include large areas of unoccupied or non-habitat), and hypothetical movement corridors. We propose that the BLM employ the practice of using “smart buffers” that are tailored to the unique topography, likelihood of animal being present, type of species habitat or resource, and the sound and viewshed unique to individual campsites, roads, or trails that are immediately adjacent to or overlap with wildlife habitat. We encourage the BLM to utilize location data from recent years (i.e. the past decade), especially in the case of plants and raptor nests which can shift year to year among alternative nests.

The Organizations stand ready to provide unbiased, professional, subject matter experts to assist the BLM in preparation of criteria for tailored set-backs for species of conservation importance.

In this way, the BLM’s decisions will be based on defensible scientific information, and in conformance with the Information Quality Act. This is just one reason why the complete planning of a much more thorough EA or Environmental Impact Statement (EIS), including robust data and transparency, is needed to evaluate proposed actions and alternatives for the planning areas.

3. The Organizations support sound scientific research as a basis for decision making by land managers. 

We request that the BLM, and their NPS partners at Canyonlands and Arches national parks, make available to the public copies of current research proposal abstracts on species named in the EAs.

4. Wildlife habitat should be based upon verifiable data and not on modeled potential habitat. 

We are concerned that recommended buffer distances for wildlife in the EAs are designed for the convenience of GIS analyses without any data that demonstrate permanent abandonment of an area or reproductive failure by the species of bird or mammal in question would result from specific camping or travel route use.

We are also concerned that BLM decisions on camping, roads, and trails could be erroneously based upon the State of Utah’s “modeled habitat”, which is really potential habitat that includes physical characteristics rather than recent occurrence data, or “occupied habitat” that is a misnomer because it encompasses large swaths of non-habitat between areas of modeled habitat, rather than inhabited areas based upon recent, verifiable radio-collar and observational data. The problem with basing restrictions on the State’s “modeled habitat” and “occupied habitat” is that those will lead to unnecessary restrictions

on the recreational community while not benefiting bighorn sheep or other species. Therefore, we urge the BLM to only base their decision-making on inhabited habitat that is based upon recent, verifiable radio-collar and observational data.

B. Bighorn Sheep

1. A narrative is developed in the Draft EAs that wildlife populations are threatened from currently regulated recreational use. 

It is important that the BLM acknowledge that there is no demographic data that indicates a long-term decline in bighorn sheep inhabiting the La Sal/Potash/South Cisco population unit, or a decline in individual bighorn sheep fitness in this population that can be directly attributable to “human use.” It is therefore disingenuous that the Labyrinth Rims/Gemini Bridges EA attempts to link a study about bighorn sheep vigilance (Sproat 2012) without first demonstrating that there has also been bighorn sheep abandonment of an area and/or population-level decline, in order to justify new camping and travel route restrictions in the EA.

As an initial matter, all the cited studies in the EA on human disturbance of bighorn sheep cited in the study share the following important characteristics:

  1. None of the studies have shown a demonstrable, causal link between human activity and population decline, loss of individual fitness, or permanent habitat abandonment that is independent of other factors (i.e. predation, disease, livestock, drought, or permanent removal due to agriculture or development).
  2. The studies rely on speculation, that the worst-case circumstances they describe “could,” “may,” or “potentially” lead to population declines. The authors of these papers generally assume, without supporting demographic data, that any observed effect in flight distance or time spent foraging or scanning results in a decrease in individual fitness and ultimately population number.
  3. Anecdotes and opinions expressed by authors, often in the conclusions or management implications of their papers, have been erroneously cited by subsequent authors, as if these anecdotes and opinions were actual demographic results. This leads to a “snowball effect” of opinions, beliefs, and biases becoming uncritically entrenched in the “scientific literature” on human disturbance of bighorn sheep. In other words, if repeated often enough, anything can take on the appearance of truth.
  4. The authors fail to acknowledge that their study population has been repeatedly exposed to humans as predators either through hunting and/or repeated capture and handling (for radio-collaring, research, or translocation). Both of these activities can be expected to result in bighorns having increased wariness around humans. The simple fact is that bighorn sheep, like many other animals, habituate to predictable and non-threatening human behavior (i.e. they will habituate to humans if they are not hunted or otherwise pursued).

Despite dire predictions of what could happen in the cited studies, there is no compelling data to indicate that the La Sal/Potash population has declined, has abandoned habitat critical to survival, or that recruitment and adult survival have been compromised due to human disturbance from recreational use, including camping. Quite to the contrary, the State of Utah allows hunting of this population on BLM and State lands outside of Canyonlands and Arches National Parks. Furthermore, this population has also had bighorn sheep regularly captured and removed for translocations elsewhere for decades.

2. The BLM presents no data on bighorn sheep locations to indicate that they are habitat limited. 

We are concerned that some of the language in the EA and proposed conservation measures are built on the false premise that the resident bighorn sheep population is in decline or in imminent threat of decline due to recreational use. However, no data are presented in the EA that bighorn or wildlife populations are in decline, or that populations are declining as a result of recreational use of a road and trail network that has been in continuous use for over 50 years. The BLM presents no data on bighorn sheep locations to indicate that they are habitat limited.

3. The EA has an over reliance on papers that misrepresent conclusions. 

In order for the BLM to take a more measured and scientifically-defensible view of the data and issues surrounding bighorn sheep in the SRMA, we ask that the BLM reconsider its reliance on the following papers as they misrepresent the factual basis of their conclusions and therefore are not up to the data quality standards required of the BLM. (Reasons are detailed in the attached reviews below). Those papers include: Papouchis et al. 2000, 2001; Sproat 2012 and Sproat et al. 2019, and Widedmann and Bleich 2014.

A review of scientific issues in Papouchis (2000, 2001): 

Papouchis did not design the study or participate in the fieldwork, but was recruited by the late Dr. Francis Singer to analyze and publish a paper out of the data gathered, essentially to salvage results from a flawed study design.

The study by Papouchis et al. (2000, 2001) was methodologically flawed and biased in its interpretation of results because the “hikers” in that study were actually researchers who used telemetry to locate radio-collared bighorn sheep and intentionally harassed them until they fled by approaching directly, off-trail and on foot. Thus, the results of Papouchis et al. (2000, 2001) were an artifact of the experimental design rather than an unbiased comparison of bighorn reaction to “hikers.” Thus, no conclusions can be drawn to hikers on trails or humans in campsites. The intentional harassment used in Papouchis et al. (2000, 2001) is clearly a different circumstance from trail hikers and even the occasional cross-country hiker who does not have the intention or means of locating, tracking, and approaching bighorn sheep until they flee. Instead, the methods of Papouchis et al. (2000, 2001), as well as similar harassment used in MacArthur (1979) and Phillips and Alldredge (2000), more closely approximated the behavior of hunters pursuing their quarry. The BLM needs to understand and acknowledge this fundamental bias in the results and conclusions of Papouchis et al. (2000, 2001).

The authors of Papouchis et al. (2000, 2001) did not acknowledge that the bighorn sheep in their study, and the population of bighorn sheep in general, had already been subject to capture and handling by humans and that bighorn in that study population are hunted on BLM land outside of the national parks. Thus, the bighorn sheep were pre-conditioned to react to humans approaching on-foot and in close proximity.

Notably, Papouchis et al. (2000, 2001) reported that the radio-collared ewes whose home ranges were along road corridors had obviously habituated to cars, and recommended that these habituated bighorn should not be captured and removed for translocations. Such captures and removals would deplete the population of resident bighorn that had habituated to habitat along roads in Canyonlands National Park, which is also a safe haven from hunting. This is an important finding because it underscores how bighorn sheep readily habituate geographically to predictable and non-threatening human activity. This habituation is also why desert bighorn sheep near Palm Springs, California wander into the suburbs and city, why hikers have to walk around them on trails, and why they have to be shooed off of lawns and golf courses in the area. Other examples of habituation in desert bighorn include those along the banks of the Green and San Juan rivers in Utah, as well as in the Grand Canyon and along roads in Canyonlands National Park.

The only quantitative data used by Papouchis et al. (2000, 2001) to distinguish human use in the high vs. low-use areas was as follows, “Approximately 1 vehicle passed along roads/hour during peak visitor months in the low-use area. … Between 5 and 13 vehicles passed along roads/hour during peak visitor months in the high-use area.” Papouchis et al. (2000, 2001) also did not mention whether this human use statistic was on paved or dirt roads, the footprint of roads in bighorn habitat, the types of use or intensity of other human use in bighorn habitat, and most importantly, differences in habitat quality which would lead to differences in bighorn sheep density and behavior. The purported increase in human use in the study area was entirely anecdotal.

A review of scientific issues in: 

Sproat 2012a, thesis, Alteration of behavior by desert bighorn sheep from human recreation and Desert Bighorn Sheep Survival in Canyonlands National Park: 2002 – 2010; Sproat 2012b, report and presentation, Potash Desert Bighorn Sheep Research; and Sproat et al. 2019, publication, Desert bighorn sheep responses to human activity in south-eastern Utah. 

The titles used by Sproat (2012) and Sproat et al. (2019) were not accurate because the authors never actually measured bighorn reactions to human activity. Instead, the authors measured scanning vs. foraging behaviors in two different areas, designated high and low human use, but made no attempt to quantify habitat differences, bighorn density, or predation rates that would have influenced their results.

The author(s) of Sproat (2012a,b) and Sproat et al. (2019) assume that a bighorn sheep observed “scanning” is looking at “threats” resulting from human use of the environment although they never consider any alternative hypotheses. Those alternative hypotheses include (a) the bighorn is looking for other bighorn sheep, (b) the bighorn is scanning to locate additional food resources, or (c) the bighorn is scanning for predators, including mountain lions, coyotes, bobcats, and golden eagles, all of which prey on bighorn sheep or their lambs. The authors present no data that time spent scanning vs. grazing has a fitness consequence to the bighorn population.

In the abstract of their paper, the authors of Sproat et al. (2019) make several bold and inaccurate statements. For example, under “Implications” the author(s) state:

“From 1979 to 2000, human recreation increased over 300% in areas occupied by desert bighorn sheep (O. c. nelsoni) in south-eastern Utah. Concurrently, the population of desert bighorn sheep occupying the Potash Bighorn Sheep Management Unit of south-eastern Utah was in steep decline.”

“We raise a cautionary flag because recreational use in bighorn sheep habitat near Moab, Utah, continues to increase and bighorn numbers continue to decline.”

However, no bighorn sheep population data was presented by the authors of Sproat et al. (2019) to support these statements. Quite to the contrary, data from the State of Utah (2019) for the La Sal-Potash population, which includes bighorn sheep in Island in the Sky, Potash, Professor Valley and Dolores Triangle subpopulations, clearly refutes this claim. The State data reveal that this population had increased despite both repeated captures and removals of bighorn sheep from the La Sal-Potash population for translocations, with 289 bighorn captured and translocated between 1982-2008, mainly from the Potash area and other parts of Canyonlands National Park (Wild Sheep Working Group 2015). Additionally, 2 to 4 bighorn sheep are hunted annually on BLM, state, and private land outside of the national parks (including the Potash area), with 31 bighorn sheep killed by hunters between 2010 and 2019 (see big game report above). This bighorn population increase also occurred despite the fact that predation accounted for 44% of radio-collared mortalities reported by Sproat (2012b). And most importantly, the bighorn population increase occurred despite the reported increase in recreational use which Sproat et al. (2019) attempted to link to a non-existent bighorn sheep decline.

Something is clearly amiss with Sproat et al. (2019) because in Sproat’s own words (Sproat 2012b, which included annual survival data from radio-collared bighorn), he concluded:

“Survival for desert bighorn sheep in CNP [Canyonlands National Park] was relatively high (83%—88%; Table 7), as evidenced by population estimates (n = 400, status = stable/increasing). Our statistical analyses indicate that temporal variables (season and month) had the greatest effect on survival.”

And in the discussion of Sproat et al. (2019), those authors state:

“We determined that bighorn sheep grazed less and scanned more in areas of high human use, but there was no apparent effect on the survival rates of adult desert bighorn sheep in the study area, as documented by Sproat (2012).”

Oddly, in the concluding sentences that follow, Sproat et al. (2019) tried to qualify this non-effect by reiterating speculation that increasing human use will have population level impacts on bighorn that needs to be mitigated and further research is needed. Specific wording includes “links among human activity, behavior of bighorn sheep and resulting consequences for fitness [which] will provide additional information useful to managers.” This inability to let go of a desired but undemonstrated research outcome is typical of some of the most frequently cited literature on human disturbance of wildlife. Also typical is the call for more data but never the critical tests that could potentially falsify their human disturbance hypothesis. It appears that Sproat (and his coauthors) were attempting to squeeze a conclusion out of data that are contrary to that conclusion.

In the discussion of their paper, Sproat et al. (2019) attempt to build a case that bighorn sheep habitat in Canyonlands is under threat of being abandoned citing other bighorn studies. Contrary to Sproat et al’s (2019) assertion, Longshore et al. (2013) did not report any abandonment of habitat or population decline in Joshua Tree National Park, instead those desert bighorn sheep ewes merely moved away from centers of human activity on busy weekends and moved back during the week when human use was lower. No deleterious effect on demography was reported. We also note that those desert bighorn sheep in Joshua Tree are not hunted. As pointed out in the attached reviews, Widedmann and Bleich (2014) did not even attempt to rule out more obvious cases for decline and eventual abandonment in a study area in North Dakota along the Little Missouri River; namely, extensive residential, commercial, and agricultural development, and suboptimal habitat to begin with. They did not rule out these factors because they never admitted that they existed.

Also cited by Sproat (2019) is the thesis by Courtemanch (2014) which presented data about constriction of winter range bighorn habitat by backcountry skiers and snowboarders in the Tetons of Wyoming. However, neither that study nor Sproat et al. (2019) mentioned the fact that bighorn sheep from the Teton bighorn population are hunted, which results in bighorn avoiding humans because they are potential predators. In addition to bighorn, mountain goats that utilize the same habitat as bighorn in the Tetons, are hunted on USFS land just outside the Grand Teton National Park. The State of Wyoming Bighorn Sheep Hunt Area #6 lists a quota of one bighorn sheep annually with a hunting season extending from August 1st through October 31st. This bighorn population also overlaps Mountain Goat Hunt Areas #2 and #5 with a current quota of 4 and 8 mountain goats respectively and a hunting season from August 15 to October 31st. While these quotas may not seem high, it is significant that hunters and their guides often spend weeks scouting and hunting in bighorn and mountain goat habitat, approaching their potential quarry as predators, and killing them with archery or rifle. Consequently, it should come as no surprise that bighorn sheep in the study by Courtemanch (2014) avoided other humans as potential predators.

Like the subpopulation studied by Wieddemann and Bleich (2014), the Grand Teton bighorn sheep population was also compromised by extensive development, as Courtemanch (2014) notes:

“The Teton bighorn sheep population has experienced numerous changes to its habitats and migration patterns due to residential development, construction of roads and fences, historical livestock grazing, and wildfire suppression, culminating in the population abandoning its traditional low elevation winter ranges (Whitfield 1983).”

Also unusual is the fact that 78% of backcountry skiers and snowboarders in the study by Courtemanch (2014) accessed the backcountry and bighorn habitat from ski lifts in Jackson Hole Mountain Resort and Grand Targhee ski resorts, a situation very different from the desert of southeastern Utah.

In conclusion, Sproat and the EA make apples-to-oranges comparison to studies with very different circumstances and uncritically accept the authors conclusions without first evaluating the assumptions, methods and data used.

A review of scientific issues in Wideman and Bleich (2014): 

The paper by Wiedmann and Bleich (2014), cited by Sproat et al. (2019) and in the EA, attempted to lay blame for the abandonment of habitat by a ewe group on construction of a trail, while ignoring other, far more obvious factors for the decline and eventual abandonment of this translocated ewe group and associated lambing area. The authors of that paper failed to account for and test other, far more obvious factors, including disease, habitat fragmentation and development. Additionally, because Wiedmann and Bleich (2014) erroneously cited the speculation in Papouchis et al. (2000, 2001) as if they were data-driven results, other authors have used this study to further reinforce their belief that human recreational disturbance of bighorn sheep is deleterious to their health and population survival. However, a closer examination of that paper reveals it to be factually deficient and misleading.

The authors of Wiedemann and Bleich (2014) failed to acknowledge that Sully Creek was a marginal site to translocate bighorn sheep into for reasons that now appear to be obvious. This area has low topographic relief as it is along the river breaks of the Little Missouri River in North Dakota. Connectivity to the northern ewe groups required that bighorn ewes migrate along a river corridor under or over the four-lane highway (Interstate 94), across a railroad track as well as across numerous paved and unpaved roads, and around development. The close proximity to the town of Medora, North Dakota and availability of private land, where the bighorn were released in the 1950’s, would inevitably lead to extensive development of the surrounding area including habitat occupied by bighorn. Seen from Google Earth historical imagery, permanent land conversion and development over the past 20 years in (and surrounding) the Sully Creek ewe home ranges and lambing areas has included: a golf course, a bible camp, agricultural field development, livestock, new private home construction, expansion of existing ranching and private land infrastructure (trailers, pens, fences, outbuildings, livestock, paved and dirt roads), oil and gas development, and artificial water ponds. This land conversion and development fragmenting and encroaching on the limited bighorn sheep habitat and movement corridors was not mentioned at all by Widedmann and Bleich (2014).

And finally, given that bighorn sheep are highly susceptible to strains of bacteria that cause fatal respiratory pneumonia in bighorn sheep and that the State of North Dakota has over 72,000 domestic sheep, it would seem obvious that disease should be strictly ruled out as a cause of decline before invoking other causes. However, none of the tonsillar swabs used to test for this disease were taken from sick or dying lambs. The only tonsil swabs were taken from healthy ewes that were captured for radio-collaring and the authors did not mention the number of samples that were taken from the Sully Creek ewe group.

In conclusion, if obvious sources of bighorn population loss, including capture and removal for translocations and ongoing mortality from hunting and predation have not been found to negatively affect population status, then why is the BLM proposing additional restrictions in bighorn sheep habitat? Can the BLM demonstrate why (and where) previous regulations and restrictions were found to be inadequate for maintaining a stable bighorn sheep population? Is the BLM willing to base its wildlife regulations on the hypothetical threat that bighorn sheep are not eating enough in areas where humans are present, based on worst-case scenarios from a study that could not find those effects? Why does the BLM not acknowledge in the EA that bighorn sheep habituate to predictable and non-threatening human behaviors?

C. Raptors

(1) Raptor Guidelines are Applicable to New Projects Rather than Existing Uses 

As stated in the 2002 raptor guidelines (Romin and Muck 2002), the guidelines are applicable to new projects and expanding development/activity, rather than existing land uses to which raptors have habituated, such as those in the SMRA. Therefore, rather than restrict or eliminate existing campsites and travel routes within the 0.5 mile one-size-fits-all buffer zone of raptor nests, as proposed in the EAs, we recommend retaining these but posting educational signage and/or physical impediments (i.e., logs or boulders) to discourage use outside of the existing campsite and travel route envelope. The BLM could also monitor these raptor nesting locations as part of its adaptive management strategy to evaluate and refine future mitigation measures with systematically collected data.

The above strategy would be separate from the process involved in the BLM evaluation of new campgrounds.

(2) Raptors and Adaptation to Human Activity 

The BLM needs to acknowledge the fact that raptors do adapt to human activity that is much closer and more intense than camping and recreational use. For example, the specific language in the Romin and Muck (2002) guidelines are as follows:

“Prior disturbance history and tolerance of raptors — As mentioned previously, some individual and breeding pairs of raptors appear relatively unperturbed by some human disturbance and human-induced impacts and continue to breed successfully amid these activities. Nesting within or near human-altered environments may be a manifestation of the decreased availability of high- quality natural nest sites; indicative of high densities of breeding birds; indicative of abundant or available prey; or simply a display of higher tolerance for disturbance by certain individuals or breeding pairs. Accordingly, it is not the intent of these guidelines to restrict current land use activities in those situations where raptors appear to have acclimated to the current level of disturbance and human-induced impacts. However, these Guidelines should be closely followed if proposed land use activities may result in exceeding the current levels and timing of disturbances.”

As discussed in the raptor guidelines, this habituation has been documented to occur at more intense levels of human disturbance, and more frequently than that associated with campsites and travel routes, trails, and current recreational activities in the planning areas:

“Some individual breeding pairs appear relatively unperturbed by human disturbance and human- induced impacts and continue to breed successfully amid development (Mathisen 1968, Bird et al. 1996). In addition, some land-use actions are potentially beneficial for some raptor species, such as: selective logging, utility lines, dams and reservoirs, farming, grazing, fire, mechanical/chemical, and public observation (Olendorff et al. 1989). For example, peregrine falcons and prairie falcons have been observed nesting on transmission towers, bridges, and buildings in many cities and raptors, including bald eagles and golden eagles, have nested within a few hundred meters of airports, blasting, construction, quarry, and mine sites (Pruett-Jones et al. 1980, Haugh 1982, White et al. 1988, Holthuijzen et al. 1990, Russell and Lewis 1993, Steenhof et al. 1993, Bird et al. 1996, Carey 1998).”

(3) Raptor Nest Buffer Distances 

Raptor Nest Buffer Distances should be revised based on data rather than opinion, as they are currently in the EAs and papers cited in the EAs. Raptor buffer distances around points, such as the 0.5 mile-radius buffer, is a one-size-fits-all buffer that lacks a sound scientific basis (e.g., data that can show a reduced survivorship of individuals or a population-level effect at distances less than this threshold). In fact, none of the species listed in the EAs are notably sensitive to human presence and the often-repeated myth of human disturbance causing nest abandonment or failure comes from decades in the past (i.e., before the 1970s and the environmental movement). Those early documented cases of “human disturbance” leading to nest failure were actually from the destruction of golden eagle nests, killing of young, and shooting of adults from the ground near nests and birds in flight from aircraft. This misguided persecution was carried out by domestic sheep producers and ranchers in the USA (Nelson 1982). In fact, Colorado had a hunting season on golden eagles until 1966. The killing of eagles by Native Americans for feathers used in ceremonial headdresses was another documented form of “human disturbance” (Nelson 1982). During the same period, “human disturbance” of peregrine falcons was from egg collectors who “roped” into nests and were mistakenly referred to in the past as “climbers.” And in Scotland and the UK, game keepers shot peregrine falcons on sight to protect game birds (Ratcliffe 1993). Although that dark chapter of persecution of raptors is now closed, some uncritical authors still conflate past human disturbance that had lethal intent, with contemporary use of the term “human disturbance” that refers to any human presence in the vicinity of nests, even if it is benign.

Experimental evidence reveals a greater tolerance of golden eagles (and other raptors) to human presence and activities than is typically parroted in the literature and in various well-intentioned guidelines that are based upon opinions rather than experimental data. Three studies on human disturbance of raptors stand out in contrast to the trend described above because they relied on controlled experiments to test the effects of human disturbance on the fitness of raptors (White and Thurow 1985, Holthuijzen et al. 1990, Grubb et al. 2007, 2010). All three utilized disturbances that were clearly threatening (e.g. blasting, threatening approach via foot/vehicle/helicopter, gunshots and noisemakers), as compared to relatively benign activities such as hiking, rock climbing, horseback riding, and driving vehicles. Yet, all three reported a remarkable tolerance of human presence, a decreased response when habituated, and recommended substantially smaller buffer zones than those typically imposed. The BLM needs to acknowledge this tolerance and habituation to human activities that are far more threatening than recreational uses in the planning areas.

More specifically, the activities include those in three studies that we’ll summarize. First, Holthuijzen et al. (1990) measured the effects of nearby blasting on nesting prairie falcons, as compared to undisturbed controls. They reported:

“This study demonstrated that, in general, blasting had no severe adverse effects on the falcon’s behavioral repertoire, productivity, and occupancy of nesting territories. Therefore, we suggest that when blasting does not occur prior to aerie selection and ceases prior to fledging, blasting that takes place at least 125 m from occupied prairie falcon aeries need not be restricted, provided that peak noise levels do not exceed 140 dB at the aerie (i.e., the noise level we measured for our experimental blasts). We recommend that no more than 3 blasts occur on any given day or 90 blasts during the nesting season.”

Second, White and Thurow (1985) used an experimental approach to quantify the effects of human disturbance on nesting ferruginous hawks. Their “low level” disturbance involved approaching nests on foot while firing a rifle every 20m, driving up to nests, and continuously operating a 3.5hp gasoline motor or noisemaker within 30-50m of a nest. They reported:

“Unlike previous reports of substantial nest desertion by raptors as a result of human activity, the number of disturbed nests that were deserted in our study was unexpectedly low.”

“Our observations suggest that a sufficient buffer zone for brief human disturbance around ferruginous hawk nests is 250 m. Adults will not flush 90% of the time if human activity is confined to distances greater than this.”

Third, Grubb et al. (2007, 2010) directly approached golden eagle nests at close range via helicopter, and quantified behavior and nest success. This study was a poignant refutation to an often repeated but erroneous perception (discussed above) that golden eagles are highly susceptible to human disturbance. The authors reported results contrary to expectations:

“Multiple exposures to helicopters during our experimentation in 2006 and 2007 had no effect on golden eagle nesting success or productivity rates, within the same year, or on rates of renewed nesting activity the following year, when compared to the corresponding figures for the larger population of non-manipulated sites. During our active testing and passive observations, we found no evidence that helicopters bother golden eagles nor disrupt nesting. In 303 helicopter passes near eagles, we observed no significant, detrimental, or disruptive responses. 96% of 227 experimental passes of Apache helicopters at test distances of 0-800 m from nesting golden eagles resulted in no more response than watching the helicopter pass (30%). “

“We found no relationship between helicopter sound levels [even though Apache helicopters were twice as loud as the civilian helicopters] and corresponding eagle ambient behaviors or limited responses, which occurred throughout recorded test levels (76.7-108.8 dB, unweighted).”

“Between all the other aircraft and human activities occurring in the Tri-Canyon Area, as well as their long term coexistance with WPG and apparent indifference to current operations, golden eagles in the area appear acclimated to current levels of activity. “

“For the specific question of WPG operating in the Tri-Canyon Area without potentially impacting nesting golden eagles, we found no evidence that special management restrictions are required. (Authors’ Note: The results of this research were very much unexpected since helicopters are usually considered more disruptive to bald eagles than any other type of aircraft. Plus, golden eagles are traditionally thought to be more sensitive, and therefore more responsive, to human intrusions than bald eagles. However, we found the golden eagles studied during this project to be just as adaptive, tolerant, and acclimated to human activities as any bald eagles in our rather considerable, collective experience with this species. We hypothesize this may at least be in part due to the proximity of the large, growing, and outdoor-oriented population of the Salt Lake Valley and Wasatch Front.

The experimental results of the three studies above should serve as an inspiration to the BLM to incorporate an adaptive management strategy into the planning process for evaluating the influence of specific types and locations of recreational use on nesting raptors.

Literature Cited 

Courtemanch AB. 2014. Seasonal habitat selection and impacts of backcountry recreation on a formerly migratory bighorn sheep population in northwest Wyoming, USA. M.Sc. Thesis, University of Wyoming, Laramie, WY, USA.

Grubb TG, Delaney DK, Bowerman WW. 2007. Investigating Potential Effects of Heli-Skiing on Golden Eagles in the Wasatch Mountains, Utah. Final Report to the Wasatch-Cache National Forest, Study No. RMRS-RWU-4251-P2-2, Agreement No. 05-JV-11221607-237, USDA Forest Service, Rocky Mountain Research Station.

Grubb TG, Delaney DK, Bowerman WW, Wierda MR. 2010. Golden eagle indifference to heli-skiing and military helicopters in northern Utah. Journal of Wildlife Management 74(6):1275-1285.

Holthuijzen AMA, Eastland WG, Ansell AR, Kochert MN, Williams RD, Young LS. 1990. Effects of Blasting on Behavior and Productivity of Nesting Prairie Falcons. Wildlife Society Bulletin 18(3):270-281

Longshore K, Lowrey C, Thompson DB. 2013. Detecting short-term responses to weekend recreation activity: desert bighorn avoidance of hiking trails. Wildlife Society Bulletin 37:698–706. doi:10.1002/wsb.349

Nelson T, Ferster C, Laberee K, Fuller D, Winters M. 2021. Crowd-sourced data for bicycling research and practice, Transport Reviews 41:1, 97-114, DOI: 10.1080/01441647.2020.1806943

Papouchis CM, Singer FJ, Sloan WB. 2000. Effects of increasing recreational activity on desert bighorn sheep in Canyonlands National Park, Utah. Pages 364 – 391 in Singer, F. J. and M. A. Gudorf. Restoration of bighorn sheep metapopulations in and near 15 national parks: conservation of a severely fragmented species. USGS Open File Report 99-102, Midcontinent Ecological Science Center, Fort Collins, CO.

Papouchis CM, Singer FJ, Sloan WB. 2001. Responses of Desert Bighorn Sheep to Increased Human Recreation. Journal of Wildlife Management 65(3):573-582.

Ratcliffe, DA. 1993. The Peregrine Falcon. 454 pp. ISBN 0856610607, 9780856610609

Romin, Laura A and James A. Muck. 2002. Utah Field Office guidelines for raptor protection from human and land use disturbances. U.S. Fish and Wildlife Service, Utah Field Office Salt Lake City.

Sproat KK. 2012. Alteration of behavior by desert bighorn sheep from human recreation and desert bighorn sheep survival in Canyonlands National Park: 2002–2010. M.Sc. Thesis, Brigham Young University, Provo, UT, USA.

Sproat KK. 2012b. Potash Desert Bighorn Sheep Research. Unpublished report. Available:

Sproat KK, Martinez NR, Smith TS, Sloan WB, Flinders JT, Bates JW, Cresto JG Bleich VC. 2019. Desert bighorn sheep responses to human activity in south-eastern Utah. Wildlife Research. Available:

State of Utah. 2019. La Sal/Potash bighorn sheep management plan. Available:

State of Utah. 2019. Available:

State of Utah. 2021. Bighorn sheep harvest data. Available:

Wiedmann BP, Bleich VC. 2014. Demographic responses of bighorn sheep to recreational activities: a trial of a trail. Wildlife Society Bulletin 38:773–782.

Wild Sheep Working Group. 2015. Records of Wild Sheep Translocations-United States and Canada, 1922-Present. Western Association of Fish and Wildlife Agencies, USA. (05/17/2015) Available:

Continue Reading