Understanding the extent to which predators engage in active search for prey versus incidentally ... more Understanding the extent to which predators engage in active search for prey versus incidentally encountering them is important because active search can exert a stabilizing force on prey populations by alleviating predation pressure on low-density prey and increasing it for high-density prey. Parturition of many large herbivores occurs during a short and predictable temporal window in which young are highly vulnerable to predation. Our study aims to determine how a suite of carnivores responds to the seasonal pulse of newborn ungulates using contemporaneous GPS locations of four species of predators and two species of prey. We used step-selection functions to assess whether coyotes, cougars, black bears, and bobcats actively searched for parturient females in a low-density population of mule deer and a high-density population of elk. We then assessed whether searching carnivores shifted their habitat use toward areas exhibiting a high probability of encountering neonates. None of t...
Trail-based recreation is a popular use of public forests in the United States, and four types ar... more Trail-based recreation is a popular use of public forests in the United States, and four types are common: allterrain vehicle (ATV) riding, mountain biking, hiking, and horseback riding. Effects on wildlife, however, are controversial and often a topic of land use debates. Accordingly, we studied trail-based recreation effects on elk (Cervus canadensis), a wide-ranging North American ungulate highly sought for hunting and viewing on public forests, but that is sensitive to human activities, particularly to motorized traffic on forest roads. We hypothesized that elk would respond to trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. We evaluated elk responses using a manipulative landscape experiment in a 1453-ha enclosure on public forest in northeast Oregon. A given type of recreation was randomly selected and implemented twice daily along 32 km of designated recreation trails over a five-day period, followed by a nine-day control period of no human activity. Paired treatment and control replicates were repeated three times per year for each recreation type during spring-fall, 2003-2004. During treatments, locations of elk and recreationists were simultaneously collected with telemetry units. Elk locations also were collected during control periods. Elk avoided the trails during recreation treatments, shifting distribution farther out of view and to areas farthest from trails. Elk shifted distribution back toward trails during control periods of no human activity. Elk avoided recreationists in real time, with mean minimum separation distances from humans that varied from 558 to 879 m among the four treatments, 2-4 times farther than elk distances from trails during recreation. Separation distances maintained by elk from recreationists also were 3-5 times farther than mean distances at which elk could be viewed from trails. Distances between elk and recreationists were highest during ATV riding, lowest and similar during hiking and horseback riding, and intermediate during mountain biking. Our results support the hypothesis that elk avoid trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. Forest managers can use results to help optimize trade-offs between competing objectives for trailbased recreation and wildlife species like elk that are sensitive to human activities on public forests.
Author contributions: BE, MR and MW conceived and designed the research; JA, BE, MR, BN and MW pe... more Author contributions: BE, MR and MW conceived and designed the research; JA, BE, MR, BN and MW performed the experiment, analyzed the data, and wrote the edited manuscript.
We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conser... more We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A-E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B-D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class-usually from E or D to D or C-from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an ongoing challenge to the improvement of future conditions for rangeland species.
We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population... more We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population viability of selected at-risk ®sh and wildlife species. The BBN models represent the ecological causal web of key environmental correlates (KECs) that most in¯uence habitat capability, potential population response for each species, and in¯uence of habitat planning alternatives. BBN models represent site-speci®c KECs, habitat capability at the subwatershed level, and pattern of habitat capability across all subwatersheds. BBNs use Dirichlet prior probability distributions and standard Bayesian updating of posterior probabilities. We derived estimates of prior and conditional probabilities from a mix of empirical data and expert judgment, mostly the latter. Sensitivity analyses identi®ed planning decisions and KECs that most in¯uence species outcomes, and can help prioritize monitoring activities. BBN models, however, substitute for neither ®eld studies nor empirical, quantitative population viability analyses of population demography and genetics. Published by Elsevier Science B.V.
Skip to Main Content. Online Library is experiencing intermittent brief disruptions when loading ... more Skip to Main Content. Online Library is experiencing intermittent brief disruptions when loading some pages - this is currently under investigation. ...
SYNOPSIS. An apparent anomaly exists in the size of riverine fish faunas of the Nile and Zaire; t... more SYNOPSIS. An apparent anomaly exists in the size of riverine fish faunas of the Nile and Zaire; the Nile while considerably longer, appears depauperate when compared with the Zaire. This paradox is explained when discharge, not length, is used as a measure of river size. Indeed, the number of freshwater fish species in African rivers is more closely related to discharge than to length or catchment area. Discharge is directly proportional to terrestrial productivity of a river basin, which in turn affects total biomass of fish and number of species. Changes in the size of rivers during the geologic past affected their capacity to sustain diverse fish faunas. Rivers flowing through especially arid lands during the late-Pleistocene were reduced in discharge, and concomitantly, fish faunas. Immigration of fish from refuge rivers during the Holocene partially restored these diminished faunas. We propose that fish are more mobile than they seem, and that the distinctiveness of riverine fish faunas may be maintained by competitive pressure from established residents, rather than by limited dispersal abilities of fish. Theories of the distribution of fish in Africa are considered, and we suggest that discharge as affected by climatic stability is largely responsible for the size of African riverine fish faunas.
We used expert opinion to evaluate the predictive reliability of a habitat effectiveness model fo... more We used expert opinion to evaluate the predictive reliability of a habitat effectiveness model for elk in western Oregon and Washington. Twenty-five experts in elk ecology were asked to rate habitat quality for 16 example landscapes. Rankings and ratings of 21 experts were significantly correlated with model output. Expert opinion and model predictions differed for 4 of the 16 landscapes. Differences were most pronounced for habitats dominated by large expanses of either forage or cover.
The primary objective of this chapter is to describe standardized methods for measuring and monit... more The primary objective of this chapter is to describe standardized methods for measuring and monitoring attributes of landscape pattern in support of habitat monitoring. This chapter describes the process of monitoring categorical landscape maps in which either selected habitat attributes or different classes of habitat quality are represented as different patch types, using maps produced by the modeling approaches described in chapter 5. Although many alternative models of landscape structure exist, such as landscape gradients (McGarigal and Cushman 2005) and graph models (Urban et al. 2009), we focus on categorical landscape maps because of their familiarity to managers, long history of use in landscape ecology, and the fact that land management agencies largely base planning and analysis on this kind of representation of landscape structure (McGarigal et al. 2009). The salamander habitat monitoring plan in chapter 10, however, provides an example of a graph model (i.e., a model of habitat connectivity for metapopulation structure). This chapter focuses on landscape pattern analysis as part of monitoring habitat for emphasis species. To use landscape metrics for model development, see Cushman and McGarigal (2002), Grand et al. (2004), and Thompson and McGarigal (2002). This chapter presents key issues that should be addressed to ensure meaningful landscape analysis, and it reviews the steps to be followed in conducting and interpreting landscape analysis in the context of habitat monitoring. We emphasize the use of FRAGSTATS (McGarigal et al. 2012) as a primary tool to quantify the composition and structure of habitat in categorical maps, given that FRAGSTATS is freely available, widely used, user friendly, and well documented, and it provides comprehensive analysis ability for categorical landscape maps (http://www.umass.edu/landeco). 6.2 Key Concepts 6.2.1 Landscape Analysis and Adaptive Management Adaptive management works by specifying resource goals, conducting management for the purpose of creating or maintaining these desired conditions, and monitoring results
Studies of habitat selection and use by wildlife, especially large herbivores, are foundational f... more Studies of habitat selection and use by wildlife, especially large herbivores, are foundational for understanding their ecology and management, especially if predictors of use represent habitat requirements that can be related to demography or fitness. Many ungulate species serve societal needs as game animals or subsistence foods, and also can affect native vegetation and agricultural crops because of their large body size, diet choices, and widespread distributions. Understanding nutritional resources and habitat use of large herbivores like elk (Cervus canadensis) can benefit their management across different land ownerships and management regimes. Distributions of elk in much of the western United States have shifted from public to private lands, leading to reduced hunting and viewing opportunities on the former and increased crop damage and other undesired effects on the latter. These shifts may be caused by increasing human disturbance (e.g., roads and traffic) and declines of early-seral vegetation, which provides abundant forage for elk and other wildlife on public lands. Managers can benefit from tools that predict how nutritional resources, other environmental characteristics, elk productivity and performance, and elk distributions respond to management actions. We present a large-scale effort to develop regional elk nutrition and habitat-use models for summer ranges spanning 11 million ha in western Oregon and Washington, USA (hereafter Westside). We chose summer because nutritional limitations on elk condition (e.g., body fat levels) and reproduction in this season are evident across much of the western United States. Our overarching hypothesis was that elk habitat use during summer is driven by a suite of interacting covariates related to energy balance: acquisition (e.g., nutritional resources, juxtaposition of cover and foraging areas), and loss (e.g., proximity to open roads, topography). We predicted that female elk consistently select areas of higher summer nutrition, resulting in better animal performance in more nutritionally rich landscapes. We also predicted that factors of human disturbance, vegetation, and topography would affect elk use of landscapes and available nutrition during summer, and specifically predicted that elk would avoid open roads and areas far from cover-forage edges because of their preference for foraging sites with secure patches of cover nearby. Our work had 2 primary objectives: 1) to develop and evaluate a nutrition model that estimates regional nutritional conditions for elk on summer ranges, using predictors that reflect elk nutritional ecology; and 2) to develop a summer habitat-use model that integrates
... Range Map: Jeff T. Price. ... of elevation (100-3150 m), but are most abundant in broad, flat... more ... Range Map: Jeff T. Price. ... of elevation (100-3150 m), but are most abundant in broad, flat valleys with extensive shrubsteppe habitat and minimal soil disturbance (Grinnell and Miller 1944; Baldwin 1956; Huey and Travis 1961; Olson 1974; Schroeder and Sturges 1975; McGee ...
Recurrent environmental changes often prompt animals to alter their behavior leading to predictab... more Recurrent environmental changes often prompt animals to alter their behavior leading to predictable patterns across a range of temporal scales. The nested nature of circadian and seasonal behavior complicates tests for effects of rarer disturbance events like fire. Fire can dramatically alter plant community structure, with important knock-on effects at higher trophic levels, but the strength and timing of fire's effects on herbivores remain unclear. We combined prescribed fire treatments with fine-scale location data to quantify herbivore responses to fire across three temporal scales. Between 2001 and 2003, 26 stands of fir (Abies spp.) and Douglas-fir (Pseudotsuga menziesii) were thinned and burned; 27 similar stands were left untreated as experimental controls. Analyzing female elk (Cervus canadensis) locations across 21 yr (1996-2016), we found crepuscular, seasonal, and successional shifts in behavioral responses to fire. Elk displayed "commuting" behavior, avoiding burns during the day, but selecting them at night. Elk selection for burns was strongest in early summer and the relative probability of elk using burns peaked quickly (5 yr post burn) before gradually returning to pre-treatment levels (15 yr post burn). Our results demonstrate that fire history has complex, persistent effects on herbivore behavior, and suggest that herbivores benefit from heterogeneous landscapes containing a range of successional stages.
Understanding the extent to which predators engage in active search for prey versus incidentally ... more Understanding the extent to which predators engage in active search for prey versus incidentally encountering them is important because active search can exert a stabilizing force on prey populations by alleviating predation pressure on low-density prey and increasing it for high-density prey. Parturition of many large herbivores occurs during a short and predictable temporal window in which young are highly vulnerable to predation. Our study aims to determine how a suite of carnivores responds to the seasonal pulse of newborn ungulates using contemporaneous GPS locations of four species of predators and two species of prey. We used step-selection functions to assess whether coyotes, cougars, black bears, and bobcats actively searched for parturient females in a low-density population of mule deer and a high-density population of elk. We then assessed whether searching carnivores shifted their habitat use toward areas exhibiting a high probability of encountering neonates. None of t...
Trail-based recreation is a popular use of public forests in the United States, and four types ar... more Trail-based recreation is a popular use of public forests in the United States, and four types are common: allterrain vehicle (ATV) riding, mountain biking, hiking, and horseback riding. Effects on wildlife, however, are controversial and often a topic of land use debates. Accordingly, we studied trail-based recreation effects on elk (Cervus canadensis), a wide-ranging North American ungulate highly sought for hunting and viewing on public forests, but that is sensitive to human activities, particularly to motorized traffic on forest roads. We hypothesized that elk would respond to trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. We evaluated elk responses using a manipulative landscape experiment in a 1453-ha enclosure on public forest in northeast Oregon. A given type of recreation was randomly selected and implemented twice daily along 32 km of designated recreation trails over a five-day period, followed by a nine-day control period of no human activity. Paired treatment and control replicates were repeated three times per year for each recreation type during spring-fall, 2003-2004. During treatments, locations of elk and recreationists were simultaneously collected with telemetry units. Elk locations also were collected during control periods. Elk avoided the trails during recreation treatments, shifting distribution farther out of view and to areas farthest from trails. Elk shifted distribution back toward trails during control periods of no human activity. Elk avoided recreationists in real time, with mean minimum separation distances from humans that varied from 558 to 879 m among the four treatments, 2-4 times farther than elk distances from trails during recreation. Separation distances maintained by elk from recreationists also were 3-5 times farther than mean distances at which elk could be viewed from trails. Distances between elk and recreationists were highest during ATV riding, lowest and similar during hiking and horseback riding, and intermediate during mountain biking. Our results support the hypothesis that elk avoid trail-based recreation similarly to their avoidance of roads open to motorized traffic on public forests. Forest managers can use results to help optimize trade-offs between competing objectives for trailbased recreation and wildlife species like elk that are sensitive to human activities on public forests.
Author contributions: BE, MR and MW conceived and designed the research; JA, BE, MR, BN and MW pe... more Author contributions: BE, MR and MW conceived and designed the research; JA, BE, MR, BN and MW performed the experiment, analyzed the data, and wrote the edited manuscript.
We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conser... more We analyzed effects of three land management alternatives on 31 terrestrial vertebrates of conservation concern within the interior Columbia river basin study area. The three alternatives were proposed in a Supplemental Draft Environmental Impact Statement (SDEIS) that was developed for lands in the study area administered by the US Department of Agriculture (USDA) Forest Service (FS) and US Department of Interior (USDA) Bureau of Land Management (BLM). To evaluate effects of these alternatives, we developed Bayesian belief network (BBN) models, which allowed empirical and hypothesized relations to be combined in probability-based projections of conditions. We used the BBN models to project abundance and distribution of habitat to support potential populations (population outcomes) for each species across the entire study area. Population outcomes were defined in five classes, referred to as outcomes A-E. Under outcome A, populations are abundant and well distributed, with little or no likelihood of extirpation. By contrast, populations under outcome E are scarce and patchy, with a high likelihood of local or regional extirpation. Outcomes B-D represent gradients of conditions between the extremes of classes A and E. Most species (65%, or 20 of 31) were associated with outcome A historically and with outcomes D or E currently (55%, or 17 of 31). Population outcomes projected 100 years into the future were similar for all three alternatives but substantially different from historical and current outcomes. For species dependent on old-forest conditions, population outcomes typically improved one outcome class-usually from E or D to D or C-from current to the future under the alternatives. By contrast, population outcomes for rangeland species generally did not improve under the alternatives, with most species remaining in outcomes C, D, or E. Our results suggest that all three management alternatives will substantially improve conditions for most forest-associated species but provide few improvements for rangeland-associated vertebrates. Continued displacement of native vegetation by exotic plants, as facilitated by a variety of human-associated disturbances, will be an ongoing challenge to the improvement of future conditions for rangeland species.
We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population... more We developed procedures for using Bayesian belief networks (BBNs) to model habitat and population viability of selected at-risk ®sh and wildlife species. The BBN models represent the ecological causal web of key environmental correlates (KECs) that most in¯uence habitat capability, potential population response for each species, and in¯uence of habitat planning alternatives. BBN models represent site-speci®c KECs, habitat capability at the subwatershed level, and pattern of habitat capability across all subwatersheds. BBNs use Dirichlet prior probability distributions and standard Bayesian updating of posterior probabilities. We derived estimates of prior and conditional probabilities from a mix of empirical data and expert judgment, mostly the latter. Sensitivity analyses identi®ed planning decisions and KECs that most in¯uence species outcomes, and can help prioritize monitoring activities. BBN models, however, substitute for neither ®eld studies nor empirical, quantitative population viability analyses of population demography and genetics. Published by Elsevier Science B.V.
Skip to Main Content. Online Library is experiencing intermittent brief disruptions when loading ... more Skip to Main Content. Online Library is experiencing intermittent brief disruptions when loading some pages - this is currently under investigation. ...
SYNOPSIS. An apparent anomaly exists in the size of riverine fish faunas of the Nile and Zaire; t... more SYNOPSIS. An apparent anomaly exists in the size of riverine fish faunas of the Nile and Zaire; the Nile while considerably longer, appears depauperate when compared with the Zaire. This paradox is explained when discharge, not length, is used as a measure of river size. Indeed, the number of freshwater fish species in African rivers is more closely related to discharge than to length or catchment area. Discharge is directly proportional to terrestrial productivity of a river basin, which in turn affects total biomass of fish and number of species. Changes in the size of rivers during the geologic past affected their capacity to sustain diverse fish faunas. Rivers flowing through especially arid lands during the late-Pleistocene were reduced in discharge, and concomitantly, fish faunas. Immigration of fish from refuge rivers during the Holocene partially restored these diminished faunas. We propose that fish are more mobile than they seem, and that the distinctiveness of riverine fish faunas may be maintained by competitive pressure from established residents, rather than by limited dispersal abilities of fish. Theories of the distribution of fish in Africa are considered, and we suggest that discharge as affected by climatic stability is largely responsible for the size of African riverine fish faunas.
We used expert opinion to evaluate the predictive reliability of a habitat effectiveness model fo... more We used expert opinion to evaluate the predictive reliability of a habitat effectiveness model for elk in western Oregon and Washington. Twenty-five experts in elk ecology were asked to rate habitat quality for 16 example landscapes. Rankings and ratings of 21 experts were significantly correlated with model output. Expert opinion and model predictions differed for 4 of the 16 landscapes. Differences were most pronounced for habitats dominated by large expanses of either forage or cover.
The primary objective of this chapter is to describe standardized methods for measuring and monit... more The primary objective of this chapter is to describe standardized methods for measuring and monitoring attributes of landscape pattern in support of habitat monitoring. This chapter describes the process of monitoring categorical landscape maps in which either selected habitat attributes or different classes of habitat quality are represented as different patch types, using maps produced by the modeling approaches described in chapter 5. Although many alternative models of landscape structure exist, such as landscape gradients (McGarigal and Cushman 2005) and graph models (Urban et al. 2009), we focus on categorical landscape maps because of their familiarity to managers, long history of use in landscape ecology, and the fact that land management agencies largely base planning and analysis on this kind of representation of landscape structure (McGarigal et al. 2009). The salamander habitat monitoring plan in chapter 10, however, provides an example of a graph model (i.e., a model of habitat connectivity for metapopulation structure). This chapter focuses on landscape pattern analysis as part of monitoring habitat for emphasis species. To use landscape metrics for model development, see Cushman and McGarigal (2002), Grand et al. (2004), and Thompson and McGarigal (2002). This chapter presents key issues that should be addressed to ensure meaningful landscape analysis, and it reviews the steps to be followed in conducting and interpreting landscape analysis in the context of habitat monitoring. We emphasize the use of FRAGSTATS (McGarigal et al. 2012) as a primary tool to quantify the composition and structure of habitat in categorical maps, given that FRAGSTATS is freely available, widely used, user friendly, and well documented, and it provides comprehensive analysis ability for categorical landscape maps (http://www.umass.edu/landeco). 6.2 Key Concepts 6.2.1 Landscape Analysis and Adaptive Management Adaptive management works by specifying resource goals, conducting management for the purpose of creating or maintaining these desired conditions, and monitoring results
Studies of habitat selection and use by wildlife, especially large herbivores, are foundational f... more Studies of habitat selection and use by wildlife, especially large herbivores, are foundational for understanding their ecology and management, especially if predictors of use represent habitat requirements that can be related to demography or fitness. Many ungulate species serve societal needs as game animals or subsistence foods, and also can affect native vegetation and agricultural crops because of their large body size, diet choices, and widespread distributions. Understanding nutritional resources and habitat use of large herbivores like elk (Cervus canadensis) can benefit their management across different land ownerships and management regimes. Distributions of elk in much of the western United States have shifted from public to private lands, leading to reduced hunting and viewing opportunities on the former and increased crop damage and other undesired effects on the latter. These shifts may be caused by increasing human disturbance (e.g., roads and traffic) and declines of early-seral vegetation, which provides abundant forage for elk and other wildlife on public lands. Managers can benefit from tools that predict how nutritional resources, other environmental characteristics, elk productivity and performance, and elk distributions respond to management actions. We present a large-scale effort to develop regional elk nutrition and habitat-use models for summer ranges spanning 11 million ha in western Oregon and Washington, USA (hereafter Westside). We chose summer because nutritional limitations on elk condition (e.g., body fat levels) and reproduction in this season are evident across much of the western United States. Our overarching hypothesis was that elk habitat use during summer is driven by a suite of interacting covariates related to energy balance: acquisition (e.g., nutritional resources, juxtaposition of cover and foraging areas), and loss (e.g., proximity to open roads, topography). We predicted that female elk consistently select areas of higher summer nutrition, resulting in better animal performance in more nutritionally rich landscapes. We also predicted that factors of human disturbance, vegetation, and topography would affect elk use of landscapes and available nutrition during summer, and specifically predicted that elk would avoid open roads and areas far from cover-forage edges because of their preference for foraging sites with secure patches of cover nearby. Our work had 2 primary objectives: 1) to develop and evaluate a nutrition model that estimates regional nutritional conditions for elk on summer ranges, using predictors that reflect elk nutritional ecology; and 2) to develop a summer habitat-use model that integrates
... Range Map: Jeff T. Price. ... of elevation (100-3150 m), but are most abundant in broad, flat... more ... Range Map: Jeff T. Price. ... of elevation (100-3150 m), but are most abundant in broad, flat valleys with extensive shrubsteppe habitat and minimal soil disturbance (Grinnell and Miller 1944; Baldwin 1956; Huey and Travis 1961; Olson 1974; Schroeder and Sturges 1975; McGee ...
Recurrent environmental changes often prompt animals to alter their behavior leading to predictab... more Recurrent environmental changes often prompt animals to alter their behavior leading to predictable patterns across a range of temporal scales. The nested nature of circadian and seasonal behavior complicates tests for effects of rarer disturbance events like fire. Fire can dramatically alter plant community structure, with important knock-on effects at higher trophic levels, but the strength and timing of fire's effects on herbivores remain unclear. We combined prescribed fire treatments with fine-scale location data to quantify herbivore responses to fire across three temporal scales. Between 2001 and 2003, 26 stands of fir (Abies spp.) and Douglas-fir (Pseudotsuga menziesii) were thinned and burned; 27 similar stands were left untreated as experimental controls. Analyzing female elk (Cervus canadensis) locations across 21 yr (1996-2016), we found crepuscular, seasonal, and successional shifts in behavioral responses to fire. Elk displayed "commuting" behavior, avoiding burns during the day, but selecting them at night. Elk selection for burns was strongest in early summer and the relative probability of elk using burns peaked quickly (5 yr post burn) before gradually returning to pre-treatment levels (15 yr post burn). Our results demonstrate that fire history has complex, persistent effects on herbivore behavior, and suggest that herbivores benefit from heterogeneous landscapes containing a range of successional stages.
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