Scott Creel

• PhD
• Professor at Montana State University

While trophy hunting provides revenue for conservation, it must be carefully managed to avoid negative population impacts, particularly for long-lived species with low natural mortality rates. Trophy hunting has had negative effects on lion populations throughout Africa, and the species serves as an important case study to consider the balance of c...

Both short-term and long-term variation in predation risk can affect the behaviour of prey, thus affecting growth, reproduction, survival and population dynamics. Inferences about the strength of such ‘risk effects’ in the wild have been limited by a lack of studies that relate antipredator responses to the magnitude of direct predation, measure re...

Inducible defences against predators evolve because they reduce the rate of direct predation, but this benefit is offset by the cost (if any) of defence. If antipredator responses carry costs, the effect of predators on their prey is partitioned into two components, direct killing and risk effects. There is considerable uncertainty about the streng...

Globally, large carnivores are declining due to direct persecution, habitat loss, and prey depletion. The effects of prey depletion could be amplified by changes in the composition of the herbivore (prey) community that provoke changes in carnivore diets, but this possibility has received little attention. We tested for changes over the past half‐c...

Interspecific competition has strongly shaped the evolution of large carnivore guilds. In Africa, the lion (Panthera leo) and spotted hyena (Crocuta crocuta, hereafter hyena) exert direct and indirect competitive impacts on each other and on subordinate guild members. The impacts of competition on demography are complex and not well understood. Wit...

Large herbivores are in decline in much of the world, including sub-Saharan Africa, and true apex carnivores like the lion ( Panthera leo ) decline in parallel with their prey. As a consequence, competitively subordinate carnivores like the African wild dog ( Lycaon pictus ) are simultaneously experiencing a costly reduction in resources and a bene...

Large carnivores such as the lion are declining across Africa, in part because their large herbivore prey is declining. There is consensus that increased protection from prey depletion will be necessary to reverse the decline of lion populations, but few studies have tested whether increased protection is sufficient to reverse the decline, particul...

Most large carnivores feed on prey infrequently and may expend large amounts of energy to locate, capture and kill their prey. This makes them probabilistically vulnerable to fluctuating rates of energy acquisition over time, especially within the increasingly human-altered landscapes that dominate their remaining range. Consequently, quantifying t...

Animal movement paths display substantial complexity and variability, leading researchers to seek underlying rules that govern these patterns and mathematical models that best describe them. Using high-resolution (≥ 10 Hz) movement from 43 vertebrate species across diverse taxa, mass, and lifestyles, we show that movement paths are universally comp...

Genetic resources for species monitoring are ideally relevant for the species’ full distribution range, feasible economically and logistically, and validated for the range of sample types collected from the field. This is particularly important for large carnivores that are elusive and wide-ranging, where individual and population processes often t...

Prey depletion threatens many carnivore species across the world and can especially threaten low‐density subordinate competitors, particularly if subordinates are limited to low densities by their dominant competitors. Understanding the mechanisms that drive responses of carnivore density to prey depletion is not only crucial for conservation but a...

Within carnivore guilds, dominant competitors (e.g., lions, Panthera leo) are limited primarily by the density of prey, while subordinate competitors (e.g., African wild dogs, Lycaon pictus) have been limited by the density of dominant competitors. Historically, the fitness and population density of subordinate competitors have not been tightly lin...

Many African large carnivore populations are declining due to decline of the herbivore populations on which they depend. The densities of apex carnivores like the lion and spotted hyena correlate strongly with prey density, but competitively subordinate carnivores like the African wild dog benefit from competitive release when the density of apex c...

Introduction Predators can affect prey not only by killing them, but also by causing them to alter their behavior, including patterns of habitat selection. Prey can reduce the risk of predation by moving to habitats where predators are less likely to detect them, less likely to attack, or less likely to succeed. The interaction of such responses to...

Interspecific competition has strong effects within carnivore guilds, and African wild dogs are strongly limited by intraguild predation by lions and food loss to spotted hyenas. The densities of these dominant competitors correlate tightly with prey density, and prey depletion due to snaring is contributing to declines of apex car-nivores across A...

Spatial patterns of and competition for resources by territorial carnivores are typically explained by two hypotheses: 1) the territorial defence hypothesis and 2) the searching efficiency hypothesis. According to the territorial defence hypothesis, when food resources are abundant, carnivore densities will be high and home ranges small. In additio...

Large herbivore migrations are imperiled globally; however the factors limiting a population across its migratory range are typically poorly understood. Zambia's Greater Liuwa Ecosystem (GLE) contains one of the largest remaining blue wildebeest (Connochaetes taurinus taurinus) migrations, yet the population structure, vital rates, and limiting fac...

Social carnivores have been central in studies of cooperative breeding, and research using noninvasive methods to examine behavioral and endocrine mechanisms of reproductive suppression started in the 1980s with dwarf mongooses in Serengeti National Park. Here, I synthesize the methods, findings and limitations of a research program that examined r...

Background Prey depletion is a threat to the world’s large carnivores, and is likely to affect subordinate competitors within the large carnivore guild disproportionately. African lions limit African wild dog populations through interference competition and intraguild predation. When lion density is reduced as a result of prey depletion, wild dogs...

Predators can impact prey via predation or risk effects, which can initiate trophic cascades. Given widespread population declines of apex predators, understanding and predicting the associated ecological consequences is a priority. When predation risk is relatively unpredictable or uncontrollable by prey, the loss of predators is hypothesized to r...

Conservation of competitively subordinate carnivores presents a difficult challenge because they are limited by dominant competitors. Prey depletion is one of the leading causes of large carnivore decline worldwide, but little is known about the net effect of prey depletion on subordinate carnivores when their dominant competitors are also reduced....

Moose populations in the northeastern United States have declined over the past 15 years, primarily due to the impacts of winter ticks. Research efforts have focused on the effects of winter tick infestation on moose survival and reproduction, but stress and nutritional responses to ticks and other stressors remain understudied. We examined the inf...

Leopards (Panthera pardus) are in range-wide decline, and many populations are highly threatened. Prey depletion is a major cause of global carnivore declines, but the response of leopard survival and density to this threat is unclear: by reducing the density of dominant competitors (lions) prey depletion could create both costs and benefits for su...

Large carnivores are experiencing range contraction and population declines globally. Prey depletion due to illegal offtake is considered a major contributor, but the effects of prey depletion on large carnivore demography are rarely tested. We measured African lion density and tested the factors that affect survival using mark–recapture models fit...

Large carnivores have experienced considerable range contraction, increasing the importance of movement across human-altered landscapes between small, isolated populations. African wild dogs (Lycaon pictus) are exceptionally wide-ranging, and recolonization is an important element of their persistence at broad scales. The competition-movement-conne...

Top predators can exert strong influences on community structure and function, both via direct, consumptive effects, as well as through non-consumptive, fear-based effects (i.e. predation risk). However, these effects are challenging to quantify, particularly for mobile predators in marine ecosystems. To advance this field of research, here we used...

Apex carnivores are wide-ranging, low-density, hard to detect, and declining throughout most of their range, making population monitoring both critical and challenging. Rapid and inexpensive index calibration survey (ICS) methods have been developed to monitor large African carnivores. ICS methods assume constant detection probability and a predict...

Large herbivore communities around the world have declined steeply in recent decades. Although excessive bushmeat harvesting is thought to be the primary cause of herbivore declines in many ecosystems, the direct effects of anthropogenic pressures on large herbivore populations remain poorly described in most of the systems experiencing decline. To...

Current extinction rates are comparable to five prior mass extinctions in the earth’s history, and are strongly affected by human activities that have modified more than half of the earth’s terrestrial surface. Increasing human activity restricts animal movements and isolates formerly connected populations, a particular concern for the conservation...

Ungulate populations face declines across the globe, and populations are commonly conserved by using protected areas. However, assessing the effectiveness of protected areas in conserving ungulate populations has remained difficult. Using herd size data from four years of line transect surveys and distance sampling models, we modeled population den...

Many studies have shown that behavioral responses to the risk posed by predators can carry costs for prey by reducing fecundity or survival, with consequent effects on population dynamics. Responses to risk include increased vigilance and reduced foraging, movement to safe habitats, increases or decreases in group size, and changes in patterns of m...

Allocating resources to growth and reproduction requires grazers to invest time in foraging, but foraging promotes dental senescence and constrains expression of proactive antipredator behaviors such as vigilance. We explored the relationship between carnivore prey selection and prey foraging effort using incisors collected from the kills of coursi...

Protected area managers need reliable information to detect spatial and temporal trends of the species they intend to protect. This information is crucial for population monitoring, understanding ecological processes, and evaluating the effectiveness of management and conservation policies. In under-funded protected areas, managers often prioritize...

Factors that limit African lion populations are manifold and well-recognized, but their relative demographic effects remain poorly understood, particularly trophy hunting near protected areas. We identified and monitored 386 individual lions within and around South Luangwa National Park, Zambia, for five years (2008–2012) with trophy hunting and fo...

Models fit to describe age and sex-specific survival in the study lion population from 2008–2015. Along with a base model derived from Rosenblatt et al. (2014) that identified cubs (0.00–1.99 years), subadults (2.00–3.99 years), and 3 adult age categories: young adults (4.00–5.99 years), prime adults (6.00–7.99 years), and old adults (≥8.00 years),...

Input data file. Final data file containing encounter histories for the period between 2008–2015. (CSV)

Best supported CJS model coefficient estimates. Coefficient estimates from the best supported Cormack-Jolly-Seber model of age, gender, and trophy hunting effects on lion survival and individual heterogeneity, season, and year effects on detection {Phi(age[0,1,2,4+) & ♀[2,4,10+) & hunting:♂[2+)), p(mixture*season*year), pi(.)}. (DOCX)

Estimated detection probability. Estimated detection probability from eight closed mark-recapture model of annual abundance assuming detection varied as a function of individual heterogeneity (plow and phigh) and season (cool dry, Apr–Sept and hot dry, Oct-Nov), {p(h2 × season),c(),pi(.)}. The mixing parameter (π) and its complement (1 –π) describi...

Predators can impact ecosystems through consumptive or risk effects on prey. Physiologically, risk effects can be mediated by energetic mechanisms or stress responses. The predation-stress hypothesis predicts that risk induces stress in prey, which can affect survival and reproduction. However, empirical support for this hypothesis is both mixed an...

Understanding the influence of environmental conditions and people on ungulate density and distribution is of key importance for conservation. We evaluated the effects of ecological and anthropogenic factors on the density of migratory wildebeest and zebra and resident oribi in Zambia's Liuwa Plain National Park where human settlements were present...

Most species adjust their behavior to reduce the likelihood of predation. Many experiments have shown that antipredator responses carry energetic costs that can affect growth, survival and reproduction, so that the total cost of predation depends on a trade-off between direct predation and risk effects. Despite these patterns, few field studies hav...

Within a large carnivore guild, subordinate competitors (African wild dog, Lycaon pictus, and cheetah, Acinonyx jubatus) might reduce the limiting effects of dominant competitors (lion, Panthera leo, and spotted hyena, Crocuta crocuta) by avoiding them in space, in time, or through patterns of prey selection. Understanding how these competitors cop...

Animals are not distributed randomly in space and time because their movement ecology is influenced by a variety of factors. Energy landscapes and the landscape of fear have recently emerged as largely independent paradigms, both reshaping our perspectives and thinking relating to the spatial ecology of animals across heterogeneous landscapes. We a...

Despite some controversy, a wide range of research across multiple taxa have established that carnivores strongly influence prey population dynamics both through direct offtake and indirect risk effects. Because of these powerful top-down effects carnivores can influence ecosystems across multiple trophic levels. Here we discuss research addressing...

African rangelands support diverse ungulate communities whose member species exhibit unique combinations of body morphology and behaviour that have evolved over millions of years to limit the effects of competition and predation on fitness, and more recently, to cope with people and livestock. The mechanisms by which native ungulates cope with the...

As global temperatures increase, interactions between species are affected by changes in distribution, abundance and phenology, but also by changes in behavior. The heat dissipation limitation hypothesis suggests that the ability to dissipate heat commonly limits the activity of endotherms, a problem that should be particularly acute for cursorial...

Human activities on the periphery of protected areas can limit carnivore populations, but measurements of the strength of such effects are limited, largely due to difficulties of obtaining precise data on population density and survival. We measured how density and survival rates of a previously unstudied leopard population varied across a gradient...

Terrestrial large carnivores have great ecological, economic and cultural importance, but are in global decline due to habitat loss, prey depletion, poaching, retributive killing and regulated hunting. While regulated carnivore hunting potentially reduces conflict with humans and livestock, increases social tolerance and provides revenue for conser...

Several elk herds in the Greater Yellowstone Ecosystem are fed during winter to alleviate interactions with livestock, reduce damage to stored crops, and to manage for high elk numbers. The effects of supplemental feeding on ungulate population dynamics has rarely been examined, despite the fact that supplemental feeding is partially justified as n...

For cooperative breeders, we hypothesize that the effects of group size on reproduction and survival might run in opposition if the benefits of grouping cannot be shared without cost. We tested this hypothesis by examining relationships between group size, survival, and reproduction in African wild dogs (Lycaon pictus), cooperative hunters with hig...

Animal group size distributions are often right‐skewed, whereby most groups are small, but most individuals occur in larger groups that may also disproportionately affect ecology and policy. In this case, examining covariates associated with upper quantiles of the group size distribution could facilitate better understanding and management of large...

1. In dryland ecosystems, mobility is essential for both wildlife and people to access unpredictable and spatially heterogeneous resources, particularly in the face of climate change. Fences can prevent connectivity vital for this mobility. 2. There are recent calls for large-scale barrier fencing interventions to address human–wildlife conflict an...

Animals that are exposed to environmental stressors may experience chronically elevated glucocorticoid (GC) levels, which can lead to deleterious effects such as immune and reproductive system suppression. Such effects are of special concern in rare species. We measured fecal GC concentrations in endangered San Joaquin kit foxes (Vulpes mocrotis mu...

Understanding the nutritional dynamics of herbivores living in highly seasonal landscapes remains a central challenge in foraging ecology with few tools available for describing variation in selection for dormant versus growing vegetation. Here, we tested whether the concentrations of photosynthetic pigments (chlorophylls and carotenoids) in forage...

Understanding how animal density is related to pathogen transmission is important to develop effective disease control strategies, but requires measuring density at a scale relevant to transmission. However, this is not straightforward or well-studied among large mammals with group sizes that range several orders of magnitude or aggregation pattern...

Background/Question/Methods The reintroduction of wolves (Canis lupus) to Yellowstone provides the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk – Cervus elaphus) in a multi-predator, multi-prey system where top-down, bottom-up, and abiotic forces on prey population dynamics were clos...

Background/Question/Methods To understand the relationship between host density and parasite transmission it is important to measure host density at a scale relevant to transmission. Among social species it is often assumed that transmission increases with increasing group size, but this may not be the case for species whose aggregation patterns...

The reintroduction of wolves (Canis lupus) to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk - Cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintrod...

Predators alter prey dynamics by direct killing and through the costs of antipredator responses or risk effects. Antipredator behavior includes proactive responses to long-term variation in risk (e.g., grouping patterns) and reactive responses to short-term variation in risk (e.g., intense vigilance). In a 3-year field study, we measured variation...

Cross-species transmission (CST) of bacterial pathogens has major implications for human health, livestock, and wildlife management because it determines whether control actions in one species may have subsequent effects on other potential host species. The study of bacterial transmission has benefitted from methods measuring two types of genetic v...

Field studies that rely on fixes from GPS-collared predators to identify encounters with prey will often underestimate the frequency and strength of antipredator responses. These underestimation biases have several mechanistic causes. (1) Step bias: The distance between successive GPS fixes can be large, and encounters that occur during these inter...

Interactions among recreational users and grizzly bears (Ursus arctos) are a continuous challenge for bear managers. Yellowstone National Park, Wyoming, USA uses a system of designated backcountry campsites to manage overnight use and provides bear-resistant food-storage devices for recreational users. Few studies have evaluated how this type of ma...

Wildlife managers often rely on permanent or temporary area closures to reduce the impact of human presence on sensitive species. In 1982, Yellowstone National Park created a program to protect threatened grizzly bears (Ursus arctos) from human disturbance. The bear management area (BMA) program created areas of the park where human access was rest...

Identifying drivers of contact rates among individuals is critical to understanding disease dynamics and implementing targeted control measures. We studied the interaction patterns of 149 female elk (Cervus canadensis) distributed across five different regions of western Wyoming over three years, defining a contact as an approach within one body le...

Packer et al. reported that fenced lion populations attain densities closer to carrying capacity than unfenced populations. However, fenced populations are often maintained above carrying capacity, and most are small. Many more lions are conserved per dollar invested in unfenced ecosystems, which avoid the ecological and economic costs of fencing.

Previous tests of the automated acoustic device, referred to as a Howlbox, effectively identified the presence of wolves (Canis lupus) during the summer, near rendezvous sites. Howlboxes are self-contained devices that broadcast simulated wolf howls and record howls made in response, and are of interest in remote locations to document the presence...

Estimates of population size are critical for conservation and management, but accurate estimates are difficult to obtain for many species. Noninvasive genetic methods are increasingly used to estimate population size, particularly in elusive species such as large carnivores, which are difficult to count by most other methods. In most such studies,...

It is increasingly common for studies of animal ecology to use model-based predictions of environmental variables as explanatory or predictor variables, even though model prediction uncertainty is typically unknown. To demonstrate the potential for misleading inferences when model predictions with error are used in place of direct measurements, we...

Large carnivore populations are in global decline, and conflicts between large carnivores and humans or their livestock contribute to low tolerance of large carnivores outside of protected areas. African lions (Panthera leo) are a conflict-prone species, and their continental range has declined by 75% in the face of human pressures. Nonetheless, la...

Although carnivores are in global decline, diverse carnivore communities are common in sub-Saharan Africa, where more than 20 species may co-occur. Though intraguild competition and predation can limit the set of species that coexist, most carnivores have traits that decrease the impacts of interspecific competition on fitness, a pattern that promo...

Apex carnivores around the world have experienced rapid population declines and local extirpation due to anthropogenic pressures, and they are increasingly restricted to government-protected areas (GPAs). Though GPAs are critical for carnivore conservation, mixed-use landscapes may be crucial for sustaining viable populations. Few studies, particul...

Recent technological advances, such as proximity loggers, allow researchers to collect complete interaction histories, day and night, among sampled individuals over several months to years. Social network analyses are an obvious approach to analyzing interaction data because of their flexibility for fitting many different social structures as well...

Many aspects of the social environment affect hypothalamic‐pituitary‐adrenal ( HPA ) axis function and increase circulating glucocorticoid concentrations. In this review, we examine the relationships between the social environment and the function of the HPA axis in vertebrates. First, we explore the effects of the social environment on glucocortic...

High seroprevalance for Brucella abortus among elk on Wyoming feedgrounds suggests that supplemental feeding may influence parasite transmission and disease dynamics by altering the rate at which elk contact infectious materials in their environment. We used proximity loggers and video cameras to estimate rates of elk-to-fetus contact (the primary...

High seroprevalance for Brucella abortus among elk on Wyoming feedgrounds suggests that supplemental feeding may influence parasite transmission and disease dynamics by altering the rate at which elk contact infectious materials in their environment. We used proximity loggers and video cameras to estimate rates of elk-to-fetus contact (the primary...

ABSTRACT Habitat modifications and supplemental feeding artificially aggregate some wildlife populations, with potential impacts upon contact and parasite transmission rates. Less well recognized, however, is how increased aggregation may affect wildlife physiology. Crowding has been shown to induce stress responses, and increased glucocorticoid (G...

Deciphering patterns of genetic variation within a species is essential for understanding population structure, local adaptation and differences in diversity between populations. Whilst neutrally evolving genetic markers can be used to elucidate demographic processes and genetic structure, they are not subject to selection and therefore are not inf...