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Food Fight: The Debate Over Grizzly Bear Foods

By Dr David Mattson


In 2009, federal endangered species protections were restored for the Yellowstone grizzly bear population in response to a court ruling that found that the government had failed to evaluate the effects of the collapse of whitebark pine, a key staple for the population. In 2013, the Interagency Grizzly Bear Study Team (IGBST) issued a report, “Response of Yellowstone grizzly bears to changes in food resources: a synthesis”, that concluded that whitebark pine was not essential for recovery of the Yellowstone grizzly bear. The IGBST has been publishing a series of related papers designed to support US Fish and Wildlife Service's 2016 draft delisting rule. 

This report has serious conceptual and other problems that show evidence of a political agenda, rather than a fair objective analysis of the science to serve the broader public interest. All of the publications that eventually presented the material covered in the Synthesis report suffer from the same flaw. The Report also flatly contradicts an overwhelming body of earlier government science showing the importance of whitebark pine to the health of the Yellowstone population, and it fails to come to grips with its own more recent data showing that, in response, bears are turning more to meat – with increasingly lethal results.  The Report furthermore suggests that since bears are omnivores, all foods are interchangeable; in other words, a salad is the same as a steak dinner. This palliative clearly fails at face value.


The adamant refusal over the last two decades by the government to allow its underlying data to be seen by outside parties is especially disturbing, especially given that tax-payers footed the bill. The solutions to the problems of the report, discussed below, include releasing all raw data for outside scrutiny, an independent outside review of the science, and a fundamental reform of the governance process to reflect the broader public trust.


“Response of Yellowstone grizzly bears to changes in food resources: a synthesis”: Rebuttal by Dr. David Mattson

The appraisal of this Report was shaped by fundamental precepts related to the public trust. The scientists who undertook and reported the research in the Report and the managers who facilitated, funded, and hastened this work are all directly or indirectly financially supported by tax payers. This means they hold a special obligation to the public to undertake, report, and apply science in a neutral and non-partisan manner. This holds especially for the USGS scientists and USFWS managers who work directly for the public and are more directly public trustees and spokespeople. Put another way, government scientists and managers who promulgate science that is distorted by a partisan agenda betray the public trust. Evidence of partisan and politicized science should be of concern to anyone who cares about good governance and a healthy democracy.

Strong evidence of a partisan political agenda need not be evidence of deliberate intent or malfeasance. No doubt the scientists who undertook the reported research think of themselves as “objective” scientists. In fact, several of them have publicly strongly asserted the case. The notion of being “objective” is a core part of most scientists’ identity. But the insidious aspect of this self-narrative is that it is invariably self-deceptive. All humans, including scientists, are slaved to their subjectivities and especially prey to bias when they fail to reflect deeply and instead bind themselves to a deceptive narrative of “objectivity” and surround themselves with a community of others who share, either explicitly or implicitly, a common normative purpose. “Group think” is one common outcome. By all of the evidence, such was the case with the scientists and managers involved in producing the Report.


The following comments are organized under broad themes, beginning with those of greater and over-arching importance and ending with a sampler of more detailed problems that, by and large, ground the main points.  


The reported research is poorly conceptualized and inattentive to important system dynamics


This problem deeply taints and permeates all of the reported research and manifests in three fundamental ways:


(1) The Report does not offer a coherent and well-articulated framework for understanding bear responses to dietary changes. Perhaps the best way to illustrate this point is by offering a conceptual frame that is, in fact, not only useful but also vital to structuring research questions and interpretations. Diet and feeding behaviors will affect bears in two fundamental ways: (i) nutritionally and (ii) by affecting hazards; i.e., the likelihood of dying. The first effect is self-evident. The net energetic benefit and fat content of foods are especially important to female condition and reproduction. Less fat and less energy gain will decrease reproductive rates—both the likelihood of reproducing and the number of cubs produced. The second effect pertains to whether use of different foods brings bears more frequently into hazardous conditions or not. This happens when use of a food brings bears more often near potential predators, especially ones that are highly lethal. Insofar as adult Yellowstone’s grizzlies are concerned, humans are far-and-away the most lethal predators, especially humans who are armed and intolerant—notably many hunters and livestock producers. Insofar as cubs and yearlings are concerned, wolves and other adult bears are additional hazards.


In this context, it is worth assessing Yellowstone’s bear foods in terms of potential nutritional benefits and relative hazards. Cutthroat trout, army cutworm moths, ungulates, and whitebark pine seeds have been energetically the richest and most abundant bear foods in the Yellowstone ecosystem. Moreover, moths, pine seeds, and ungulates during fall are a rich source of fat. On this basis, moths and fall ungulates are energetically good replacements for whitebark pine seeds—assuming that the abundance and distributions of these foods are comparable.


Insofar as hazards are concerned, any food that tends to be distributed in areas or in ways that reduce exposure to humans, wolves, and other adult bears is a superior food. There is no doubt that whitebark pine seeds have been the safest food for females and their cubs to consume. Moths are remote from humans, but tend to concentrate bears near each other. By contrast, meat is indisputably the most hazardous food for of all ages and both sexes to eat, especially when consumption of meat increases exposure of cubs and yearlings to wolves and other bears—as with the scavenging of larger carcasses—or to armed intolerant people—as with scavenging of guts piles and other remains left by hunters, and with depredation or scavenging of livestock.


Parenthetically, the Report’s authors conflate farness from roads with the hazards of foraging. Hence, the awkwardness of the authors asserting that bears do not forage in less safe areas (i.e., nearer roads) in the absence of whitebark pine seeds, while at the same time presenting results showing that more bears die during poor seed crops and that more bears concentrate near roadsides. Some foods (e.g., yampa, pocket gophers) do bring bears nearer people, but often under circumstances where the involved people are not particularly lethal—as in Yellowstone Park. On the other hand, meat can draw bears into highly lethal circumstances, not uncommonly involving gut piles and livestock, in areas that are greater than 500m from a road.  


In summary, whitebark pine seeds indisputably have been the safest and nutritionally most beneficial food for Yellowstone’s female grizzlies, and the turn to eating more meat has probably yielded comparable energetic returns, but with substantially increased hazards to the bears. Thus, one would not expect any dramatic downturn in body condition or cub production with loss of whitebark pine, but, rather, an increase in mortality among cubs and yearlings everywhere and among adults outside of the National Parks where adults are exposed to livestock producers and big game hunters.


Which is exactly the result of the research presented in the Report. Nonetheless, the Report’s authors leave readers with the impression that loss of whitebark pine has been of no consequence to Yellowstone’s grizzly bears. Moreover, the reported research does not in any way address trends in meat resources, elk and bison in particular, nor other major trends in Yellowstone’s grizzly bear habitat which would almost certainly affect the behaviors and vital rates investigated by the Report’s scientists; which leads to the next point.


But before moving on it is worth emphasizing a critical conclusion: despite its advertised purpose, this Report offers a remarkably simple-minded and even incoherent framework for, in fact, understanding bear responses to dietary changes. Moreover, this lack of coherency allows for and even encourages post hoc arguments and interpretations that accommodate a partisan representation of the research results. This is, quite simply, shoddy science which cannot be remedied by any amount of statistical gimcrackery.


(2) The Report does not explicitly consider the effects of other on-going trends in Yellowstone’s grizzly bear foods and habitat. It is in some ways remarkable the extent to which the Report’s scientists bounded their consideration of environmental effects. Despite reference, when convenient, to the diversity of Yellowstone’s grizzly bear diet, with emphasis on moths, cutthroat trout, ungulate meat, and whitebark pine seeds as being energetically the most important, virtually all of the reported research explicitly considers only changes in whitebark pine seeds. Change in abundance of whitebark pine is then competed with the effects of a variety of different time periods and an index of density to explain changes in behaviors and vital rates. Period.


This circumscription of effects considered by the Report’s authors is bizarre in light of demonstrable trends in Yellowstone’s grizzly bear habitat (Figures 1-7; appended). Just as a sampler, the period (1983) 1989-1999 saw the advent and increasing use of moths and moth sites, peak abundance of elk and the central Yellowstone bison populations, abundant spawning cutthroat trout, slightly elevated growing season temperatures, and comparatively wet growing seasons. The period 2000-2004 saw not only the beginning of the decline of whitebark pine, but also intermediate-sized cone crops, the beginning of the decline of elk populations, major declines in cutthroat trout, and a period of exceptionally severe drought. Finally, by contrast, the period 2007-2012 saw nigh on to catastrophic declines of some elk populations, whitebark pine seeds, and cutthroat trout, highly variable but warm growing seasons, intermediate levels of drought, increased numbers of bears on moth sites, and (on average) increased cone crops on the whitebark pine trees that had survived. Which begs the question: Why did the Report’s authors not explicitly consider any of these other habitat effects (but see comments on the partisan nature of the science below)?


All of these other habitat changes are correlated with time. This translates into a critical short-coming in virtually all of the reported research. All of these other habitat changes are subsumed in the putative effects of the various time periods that the Report’s authors employ or in the index of density, which is also correlated with time. Which leads to the concluding point of this section: time period and “density dependence” are essentially meaningless as explanations for anything.


(3) The Report deploys concepts that are essentially meaningless as alternate explanations for behaviors and vital rates. Time period, in and of itself, is self-evidently without any meaning other than as a surrogate for other things that might be going on. This is, in fact, how time period is employed in their analyses by the Report’s authors. But they then arbitrarily delimit what time period means, without any consideration given to the many other substantial habitat changes afoot (Figures 1-7). All of the other habitat effects are subsumed within, undifferentiated and unacknowledged. At best this could be considered a result of thoughtlessness and lack of sophistication.


Likewise, several particularly thoughtful scientists have remarked that “density” is not a mechanism, but, rather, a surrogate for interactions of animals with each other and with other species organized in space and around resources. Increasing densities of bears (assuming such has been the case) do not somehow automatically result in bears spontaneously dropping dead or failing to give birth. A good share of the “effects” of density on birth and death rates are a result of real interactions with other bears and with other species such as wolves and people, strongly influenced by the extent to which there is scramble competition for foods or accessing foods affects hazards (see above). More specifically, it is likely that the decline in cub and yearling survival is less a consequence of density, as such, and more a consequence of increasing reliance by female bears on meat, where cubs and yearlings are at greater risk of death from other bears, wolves, and humans.


As a final note on the density concept, the Report’s authors deploy the term as if density-dependent effects have been amply demonstrated for bears in multiple areas. However, the only research they (repeatedly) reference was undertaken in Sweden in habitat that was (by all indications) relatively static and in which human lethality was better controlled than in the Yellowstone ecosystem, which would allow for greater attribution of demographic effects to social interactions of bears, as such (i.e., “density”). This key contextual difference essentially debars any relevance to the highly dynamic conditions of Yellowstone’s grizzly bear habitat. But the Report’s authors do not anywhere note this critical consideration.

As a bottom line, the substitution of “density” and abstract time periods by the Report’s authors for the host of other environmental effects afoot, and their related assertions about the putative effects of these non-factors is disingenuous, thoughtless…and shoddy science.

There are other issues with the report


The extent to which the reported research substitutes pseudo-variables for a number of important habitat dynamics alone precludes giving much credence to any of what the Report (and derivative publications) offers. In addition, any substantive appraisal depends, at a minimum, on access to the full manuscripts and details of methods and, better yet, on access to the data that were used. However there are issues with the research and the Report, even taking the results at face value.


(1) There are major problems with the interpretation of research results by the Report’s authors. As noted above, some of the reported research provides support for an alternative coherent story—not articulated by the Report’s authors—about what has happened during the last 10-15 years with behavior and demography of Yellowstone’s grizzly bears. Use of whitebark pine has apparently declined along with selection for whitebark pine habitats, but with continuing effects of whitebark pine seed crop size on frequency of roadside feeding and levels of mortality both within and outside the recovery zone, at the same time that grizzlies have increasing turned to eating meat with accompanying increases in cub and yearling mortality. This story is consistent with other data not presented in the Report: of mounting depredation and conflicts with livestock producers especially to the southeast of the ecosystem and of a long term trend toward proportionately increasing conflicts with hunters. There has also been a symmetrical proportional increase in number of grizzly bear deaths linked to livestock and hunters along with substantial increases in absolute numbers of grizzlies dying. This increasing mortality coupled with longer-term declines in recruitment would readily explain the stalling if not decrease in the Yellowstone grizzly population. This is a compelling account supported by the available evidence, yet the authors of the Report give such an interpretation no credence whatsoever in their apparent rush to conclude that whitebark pine has had no effect on the Yellowstone grizzly bear population.


By contrast, all of the evidence offered by the authors that might be considered at odds with the alternate interpretation offered here is either highly suspect, extraneous, or deeply contradictory. For example, the authors’ claim that, when whitebark pine is less abundant, bears do not forage in more hazardous environments, is at odds with the turn to eating more meat, continued increases in bear mortality, increasing conflict with hunters and livestock producers, and the stalling (if not decline) of the population. None of these contradictions are adequately explained by the authors, which compounds the problem noted before of the erroneous equation of remoteness from roads with the hazards of using different foods. The analysis of vital rates is rendered more or less meaningless by use of time period (and, by implication, density) as an explanatory variable (see above) and fails to reconcile the described changes in reproductive and survival rates with the flattening if not decline in population growth. At best the authors imply (but don’t state outright) that reduced cub and yearling survival resulted in slower population growth—while at the same time making the contradictory case that adult female survival was the more critical phenomenon.  Moreover, it is unclear why the authors chose to focus on (in effect) reproductive interval rather than litter size when previous research has shown litter size to be more sensitive to availability of whitebark pine seed crop size. Finally, results of the home-range-size and movements analyses only relate very weakly and indirectly to the issues of diet, hazards, and vital rates.


Of relevance here as well, the Report’s authors fail to reconcile their results with the large body of previous research showing major effects of whitebark pine on behavior and demography of Yellowstone’s grizzly bears. As the authors note, this previous research demonstrated substantial effects of whitebark pine on distributions of bears, conflict with humans, use of alternate foods, and reproductive and survival rates. On the one hand the Report’s authors seem to claim that consumption of meat has fully compensated demographically and otherwise for loss of whitebark pine, but then fail to present any direct evidence of a meat effect on either reproduction or survival, while at the same time presenting evidence of continuing effects of whitebark pine on levels of mortality. The authors also fail to address previously-documented differences in distributions of various sex, age, and reproductive classes of bears relative to humans in response to other bears and variations in whitebark pine seed crops. It is unclear whether the analysis of habitat use addressed these sex-age distinctions and, whether, as previously found, there was evidence of differential distributions relative to people. Instead, the authors make blanket statements about “bears.”   


Perhaps the most egregious short-coming of the interpretation offered by the Report’s authors is in their treatment of diet variation and diversity. The Report’s authors frequently imply, or even state outright that, because grizzly bear diets vary in time and space, there are few if any demographic implications of this variation. In other words, according to this account, it doesn’t matter, demographically, what Yellowstone’s grizzly bears eat. This is nonsense. Clearly, any bear you encounter will have eaten something to stay alive, but this does not mean the bear will be as productive or as likely to stay alive if the consumed foods have less energetic benefit, less fat content, and engender greater hazards while being used. Moreover, there is ample evidence of diet quality translating into sometimes substantial differences in densities of bear populations. Just because some bear(s) will eat false truffles, biscuitroots, yampa roots, berries, or pocket gophers during some years or seasons does not mean it is faring as well as when it was eating trout, pine seeds, moths, or ungulate meat. The treatment of diet diversity by the Report’s authors is truly bemusing and leaves one groping for an explanation, with ignorance being unlikely, and the blind pursuit of a partisan agenda the more probable cause.


The take home message here is: the Report’s authors clearly offered ad hoc interpretations that served the purpose of reaching foregone conclusions shaped by a political agenda (see below). And, as noted above, this biased interpretation was abetted by the authors’ failure to articulate and adhere to a comprehensive and insightful conceptualization of the research problem and the investigated system.       


(2) There are additional potential problems with explanatory variables. There are potentially many issues with the analyses undertaken by the Report’s authors, but lack of access to a full account of the data and methods precludes any definitive commentary. However, the Report does present enough information to flag several potential problems.

Insofar as the analysis of whitebark pine habitat use is concerned, there are two potentially major issues. One is evident in the map of whitebark pine distribution that the Report provides. Quite simply, it is not accurate, especially in failing to depict whitebark pine at lower elevations (down to 7900-8000’) on the central and Madison Plateaus, the very areas where the Report’s authors claim that whitebark pine is absent. We know that mature seed-producing whitebark pine occur in these areas…because the grizzly bears have shown us. During years of very large pine seed crops, as occurred during 1978-1979, virtually every radio-marked grizzly bear in all parts of the ecosystem, including western parts, was consuming whitebark pine seeds, not uncommonly from red squirrel middens located under an isolated stand of whitebark pine on a rocky outcropping in a forest otherwise comprised of lodgepole pine. This error of omission calls into question claims made by the authors regarding “absence” of whitebark pine distribution in a substantial percentage of Yellowstone grizzly bear ranges. Their statements are simply not true.


The second potential issue with the authors’ analysis of selection for whitebark pine habitats has to do with how these habitats were defined. Previous research has shown that strongest selection for whitebark pine habitats by grizzly bears occurs at lower elevations where whitebark pine is intermixed with other tree species, and where red squirrels are abundant. By contrast, grizzlies have been shown to select against higher-elevation stands of pure or near-pure whitebark pine. The implication here is that, if the author’s pooled high and low elevation whitebark pine habitats, they would mask important differences in selection and underestimate selection for the most critical of whitebark pine habitats. They may have made such a distinction, but the Report fails to provide this information—which is emblematic of the problems associated with releasing such politically sensitive research in such a hasty and only partially described manner.       


Finally, without being comprehensive, there is reason to be concerned about the veracity of the bear density index used by the Report’s authors. The performance of this index is critical because of the extent to which it is invoked as an explanatory variable. Given the Report’s description, this index appears to be fundamentally driven by the number of bears trapped in a given 14 x 14 km area. Systematic time-specific adjustments were apparently then made using population-averaged survival rates to derive time-specific density estimates. The concern, then, is whether trapping effort is random with respect to density. The authors provide no evidence of this but instead assert that trapping effort was somehow “representative.” Given the importance placed on this metric, such assertions are not sufficient and, indeed, there is no evidence that trapping effort within the Yellowstone ecosystem has been anything close to random—or even systematic.


The Report’s authors claim to have confirmed their index of bear density through correlation with an “independent” measure of grizzly bear distribution: number of bear observed during hour of flight reckoned for 1000 km2 area. This test only has merit to the extent that the two measures are, in fact, independent. The authors provide no evidence that this is so. By contrast, it could be the case that trapping effort tended to gravitate toward where more bears had been seen during aerial oversights. It’s hard to know, which is to say, this is a particularly pointed instance where lack of access to data and a detailed description of methods preclude meaningful assessment of science that is driving a critically important management decision.    


(3) The analysis of body fat is suspect. The structure and conceptualization of the updated analysis of body fat presented in the Report is highly suspect. There are several issues. For one, the authors yet again conflate time period with a tacit control for all things other than loss of whitebark pine, assuming that they then have the ability to isolate a whitebark pine-related effect, which, as indicated above, is not the case. Interpretation of any results between or among time periods is confounded by a number of environmental factors that were not considered in the analysis. Moreover, the author’s fail to consider the fact that average cone production increased by roughly 1.6 times on surviving trees during the 2008-2013 period compared to the 2000-2004 period, which would have masked the effects of tree mortality.

Another factor is that the sample size is small enough to preclude any statistical power; i.e., the ability to detect differences. This is relevant to interpretation of the effects plots presented on page 20 of the Report, where, by visual inspection, one can see a lessening of seasonal body fat accumulation during the 2008-2013 period compared to the 2000-2004 period and a tendency for younger bears sampled during poor seed crops years to fall below the central tendency during the earlier period as well—yet none of the effects were apparently detected statistically. Another related concern is whether the small sample of bears is representative of the population at large, especially in consumption of various foods. There is good reason to suspect that the sample is not, indeed, representative (or random) given that consumption of foods probably does not vary independently of the likelihood that a bear will be captured, especially for management purposes and probably even by researchers.


The reported research is motivated and framed by a political agenda

Many of the otherwise bewildering short-comings of the Report’s science are explicable when understood as a political endeavor. The reported research was clearly motivated by and shaped to address and rebut rulings by the federal District Court of Montana and Ninth Circuit Court of Appeals. These rulings focused on the USFWS’s failure to consider loss of whitebark pine during an earlier effort to delist Yellowstone’s grizzly bear population. The USFWS unsuccessfully tried to argue that the Yellowstone grizzly bear population was increasing, apparently without end, without any effects of whitebark pine loss, and with “density-dependence” as the only likely effect on vital rates. After its losses, the USFWS clearly set out to prove its case with the help of USGS scientists by setting up a dueling dichotomy of effects attributable to density versus whitebark pine. The limited conceptualization and structure of the USGS analysis thus becomes explicable: it was dictated by the political agenda of the USFWS in reaction to its losses in court.


The political nature of the reported science is further evident in the highly unusual departure from USGS’s Fundamental Science Practices. This code rather unequivocally mandates that all USGS research undergo internal and external peer and other bureau reviews before being publicly released. The Report’s Disclaimer (page ii) signifies what would in other contexts be a major infraction of this USGS policy; which clearly signals that approval for release was obtained at the highest levels of the USGS, probably at the request of those at the highest levels of the USFWS. Which begs the question, why? Why the hurry to get such a report on the streets, even in violation of the spirit and intent of USGS Fundamental Science Practices?

The answer to this somewhat rhetorical question is pretty straight-forward: the USFWS is clearly set on beginning the delisting process for Yellowstone’s grizzly bear population during 2014 and needed the science to be available to managers of the Interagency Grizzly Bear Committee (IGBC) so as to set the stage for a vote by this body in support of delisting; which has, in fact, happened. If the science remained “unreported,” such a vote would have to wait upon the next round of IGBC meetings, which would delay the move to delist.   


Put another way, the political nature of the reported science is equally evident in the remarkable lack of genuine curiosity exhibited by the Report’s authors regarding what is actually going on with Yellowstone’s grizzly bears and their habitat.  There was no indication that the authors really wanted to understand how all of the moving pieces in Yellowstone’s world was affecting both the current and future prospects of the grizzly bear population. By contrast, what was clearly evident was an interest in a highly limited political framing of the research followed by a partisan interpretation that would allow the USFWS to claim in court that Yellowstone’s grizzly bears were unaffected by loss of whitebark pine.


All of this is a betrayal of the public trust. Yellowstone grizzly bear researchers and managers are paid annual salaries totaling millions of dollars to inquire honestly and skillfully into the ecology and demography of the bear population, and then to present those results in a way that gives due regard to uncertainties and risks. There is a tempo to this case that signifies a profound lack of due deliberation on the part of scientists and managers. The glut of science described in the Report is clearly being hastily promulgated without regard for the quality of review or open scientific debate.


Concluding thoughts

There are perhaps two robust conclusions that can be drawn from the Report. First is that the federal government can bury us with shoddy science if it devotes its resources to the task. Second is that the Report is the result primarily of a political rather than scientific process. Which is not to say that the involved scientists think of themselves as being partisan or political. Some of the potential reasons for this seeming paradox are covered in the Introduction. This Report is more than anything else a striking example of what one can get when a business model of scientific practice is coupled with a monopoly on data, amplified by a highly inflamed political context and enmeshment in a set of cultural preferences.

USGS has constructed a model of its scientific enterprise that is informed by corporate America, that is, of providing a “service” to customers or clients. The service is science, and most of it is paid for by customers, who, under this model, happen to be primarily other Bureaus within the federal government. USGS scientists, such as those who produced this report, are beholden to “serve” their fellow Bureau customers, the aegis of which includes contractual monetary arrangements. In this case, the primary “customer” is the USFWS. Moreover, representatives of the USFWS are and were deeply involved in shaping the science in the Report along with its delivery.


The results are insidious. The USGS science might have turned out different than it did if the USFWS and other involved “customers” were in fact neutral arbiters of the public interest. However, there is ample evidence that the USFWS and other government bureaus pursue their own special interests, and that professionals within these bureaus pursue special interests of their own. Thus you see agencies acting in ways that reflect their budgetary concerns, political relations with Congress, cozy relations with entities that they supposedly regulate, or just simply the ego demands of professionals within. Without going into details, it seems safe to assume that all of this applies to the USGS, the USFWS, and relations between them.  


Compound this by involving state wildlife agency biologists and managers in not only executing the science, but also in shaping the science agenda. This has been very much the case with the science described in the Report. The states are involved in two ways: 1) as members of the Interagency Grizzly Bear Committee, which is also considered to be a USGS “customer,” and 2) as active participants in the research, both collecting and analyzing data. The problem with the states is that they have considerable vested interests in delisting. The wildlife management agencies of Wyoming, Idaho, and Montana have made no bones about their great desire to delist Yellowstone’s grizzly bears so that they can take over management and institute a sport hunt. And state agencies are hardly paragons of representative governance. Rather, there is ample evidence showing they are a despotic institution designed to serve the interests of a minority of sport hunters.


Finally, add in the especially problematic monopolistic arrangements of Yellowstone’s grizzly bear science. Under terms of the ESA the USFWS has final permitting authority over what science can get done with Yellowstone’s grizzly bear, and almost invariably the permitted science is executed by the USGS Interagency Grizzly Bear Study Team and scientists whom they invite to participate. Period. Thus, you have a monopoly of permitted inquiry. On top of this, there is only one data set for Yellowstone’s (currently) threatened grizzly bear population; so only one set of scientists who are part of a closed community, in service of “customers” who have considerable vested interests, inquiring into a single data set that is essentially unavailable to anyone else. This is a sure fire recipe for all sorts of politically-informed bias to insinuate itself into the process of scientific inquiry. Hence, the Report.


Figure 1. Annual elk population estimates for the Yellowstone northern elk population (a) and the Firehole-Madison elk population (b)


Figure 2. Annual estimates of calf:cow ratios for Yellowstone region elk populations, Montana and adjacent Wyoming (a) and other Wyoming populations (b) from Middleton et al. (2013)


Figure 3. Number of spawning cutthroat trout counted in front country streams (gray line) and in Clear Creek (blue line) (a), and index of bear activity along front country streams (b) tributary to Yellowstone Lake.


Figure 4. Annual growing season temperatures (a) and annual Palmer Drought Index (b), both averaged for April-August in upper Yellowstone climate region. The heavy red line is a 3-year moving average.


Figure 5. Annual estimates of number of moth sites used by grizzly bears in the Yellowstone ecosystem (top green line) as well as total numbers of bears observed on moth sites (bottom gray line).


Figure 6. Average number of cones counted on whitebark pine trees on fixed transects (gray dots and line) with 3-year moving average (green line. The cone crop averages for 2000-2004 and 2008-2012 are also shown.


Figure 7. Annual bison population estimates for Yellowstone National Park herds.




Delisting: a bad idea

Yellowstone’s grizzly bear population is still not recovered! Yellowstone’s population of roughly 690 grizzly bears is completely isolated from all other grizzly bear populations and much smaller than the 2000+ animals widely considered necessary for long-term viability. 

Agency Spin

Read a summary of the key claims of being made by government scientists and managers, and a  response to each. its necessarily long due to the complexity of the issues presented. But its worth understanding what is really going on.

About the Food Fight

In 2009, federal endangered species protections were restored for the Yellowstone grizzly bear population in response to a court ruling that found that the government had failed to evaluate the effects of the collapse of whitebark pine, a key staple for the population. In 2013, the Interagency Grizzly Bear Study Team (IGBST) issued a report, “Response of Yellowstone grizzly bears to changes in food resources: a synthesis”, that concluded that whitebark pine was not essential for recovery of the Yellowstone grizzly bear.  

Public Backs Bears

In the public processes related to management of Yellowstone grizzly bears during the last two decades, the public has come out swinging for bears and their habitat. 

Read about it here.

What the People Say

According to the U.S. Fish and Wildlife Service (FWS), over 650,000 comments were submitted on the 2016 proposal to remove endangered species protections (“delist”) the Yellowstone grizzly bear.  Over 99% of those comments opposed delisting.  

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