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Top-down effects of apex predators are modulated by human impacts on community composition and species abundances. Consequently, research supporting top-down effects of apex predators occurs almost entirely within protected areas rather than the multi-use landscapes dominating modern ecosystems. Here, we developed an integrated population model to disentangle the concurrent contributions of a reintroduced apex predator, the grey wolf, human hunting and prey abundances on vital rates and abundance of a subordinate apex predator, the puma. Increasing wolf numbers had strong negative effects on puma fecundity, and subadult and adult survival. Puma survival was also influenced by density dependence. Overall, puma dynamics in our multi-use landscape were more strongly influenced by top-down forces exhibited by a reintroduced apex predator, than by human hunting or bottom-up forces (prey abundance) subsidized by humans. Quantitatively, the average annual impact of human hunting on equilibrium puma abundance was equivalent to the effects of 20 wolves. Historically, wolves may have limited pumas across North America and dictated puma scarcity in systems lacking sufficient refugia to mitigate the effects of competition. [ABSTRACT FROM AUTHOR]

As technology has improved, our ability to study cryptic animal behavior has increased. Bed site selection is one such example. Among prey species, bed site selection provides thermoregulatory benefits and mitigates predation risk, and may directly influence survival. We conducted research to test whether a subordinate carnivore also selected beds with similar characteristics in an ecosystem supporting a multi-species guild of competing predators. We employed a model comparison approach in which we tested whether cougar (Puma concolor) bed site attributes supported the thermoregulatory versus the predator avoidance hypotheses, or exhibited characteristics supporting both hypotheses. Between 2012-2016, we investigated 599 cougar bed sites in the Greater Yellowstone Ecosystem and examined attributes at two scales: the landscape (second- order, n = 599) and the microsite (fourth order, n = 140). At the landscape scale, cougars selected bed sites in winter that supported both the thermoregulatory and predator avoidance hypotheses: bed sites were on steeper slopes but at lower elevations, closer to the forest edge, away from sagebrush and meadow habitat types, and on southern, eastern, and western-facing slopes. In the summer, bed attributes supported the predator avoidance hypothesis over the thermoregulation hypothesis: beds were closer to forest edges, away from sagebrush and meadow habitat classes, and on steeper slopes. At the microsite scale, cougar bed attributes in both the winter and summer supported both the predator avoidance and thermoregulatory hypotheses: they selected bed sites with high canopy cover, high vegetative concealment, and in a rugged habitat class characterized by cliff bands and talus fields. We found that just like prey species, a subordinate predator selected bed sites that facilitated both thermoregulatory and anti-predator functions. In conclusion, we believe that measuring bed site attributes may provide a novel means of measuring the use of refugia by subordinate predators, and ultimately provide new insights into the habitat requirements and energetics of subordinate carnivores. [ABSTRACT FROM AUTHOR]

In this study, we estimate life history parameters and abundance for a protected jaguar population using camera-trap data from a 14-year monitoring program (2002–2015) in Belize, Central America. We investigated the dynamics of this jaguar population using 3,075 detection events of 105 individual adult jaguars. Using robust design open population models, we estimated apparent survival and temporary emigration and investigated individual heterogeneity in detection rates across years. Survival probability was high and constant among the years for both sexes (φ = 0.78), and the maximum (conservative) age recorded was 14 years. Temporary emigration rate for the population was random, but constant through time at 0.20 per year. Detection probability varied between sexes, and among years and individuals. Heterogeneity in detection took the form of a dichotomy for males: those with consistently high detection rates, and those with low, sporadic detection rates, suggesting a relatively stable population of ‘residents’ consistently present and a fluctuating layer of ‘transients’. Female detection was always low and sporadic. On average, twice as many males than females were detected per survey, and individual detection rates were significantly higher for males. We attribute sex-based differences in detection to biases resulting from social variation in trail-walking behaviour. The number of individual females detected increased when the survey period was extended from 3 months to a full year. Due to the low detection rates of females and the variable ‘transient’ male subpopulation, annual abundance estimates based on 3-month surveys had low precision. To estimate survival and monitor population changes in elusive, wide-ranging, low-density species, we recommend repeated surveys over multiple years; and suggest that continuous monitoring over multiple years yields even further insight into population dynamics of elusive predator populations. [ABSTRACT FROM AUTHOR]

Several conceptual models describing patterns of prey selection by predators have been proposed, but such models rarely have been tested empirically, particularly with terrestrial carnivores. We examined patterns of prey selection by sympatric wolves (Canis lupus ) and cougars (Puma concolor ) to determine i) if both predators selected disadvantaged prey disproportionately from the prey population, and ii) if the specific nature and intensity of prey selection differed according to disparity in hunting behavior between predator species. We documented prey characteristics and kill site attributes of predator kills during winters 1999–2001 in Idaho, and located 120 wolf-killed and 98 cougar-killed ungulates on our study site. Elk (Cervus elephus ) were the primary prey for both predators, followed by mule deer (Odocoileus hemionus ). Both predators preyed disproportionately on elk calves and old individuals; among mule deer, wolves appeared to select for fawns, whereas cougars killed primarily adults. Nutritional status of prey, as determined by percent femur marrow fat, was consistently poorer in wolf-killed prey. We found that wolf kills occurred in habitat that was more reflective of the entire study area than cougar kills, suggesting that the coursing hunting behavior of wolves likely operated on a larger spatial scale than did the ambush hunting strategy of cougars. We concluded that the disparity in prey selection and hunting habitat between predators probably was a function of predator-specific hunting behavior and capture success, where the longer prey chases and lower capture success of wolf packs mandated a stronger selection for disadvantaged prey. For cougars, prey selection seemed to be limited primarily by prey size, which could be a function of the solitary hunting behavior of this species and the risks associated with capturing prime-aged prey. [ABSTRACT FROM AUTHOR]

Carrion promotes biodiversity and ecosystem stability, and large carnivores provide this resource throughout the year. In particular, apex felids subordinate to other carnivores contribute more carrion to ecological communities than other predators. We measured vertebrate scavenger diversity at puma ( Puma concolor ) kills in the Greater Yellowstone Ecosystem, and utilized a model-comparison approach to determine what variables influenced scavenger diversity (Shannon's H ) at carcasses. We documented the highest vertebrate scavenger diversity of any study to date (39 birds and mammals). Scavengers represented 10.9% of local birds and 28.3% of local mammals, emphasizing the diversity of food-web vectors supported by pumas, and the positive contributions of pumas and potentially other subordinate, apex felids to ecological stability. Scavenger diversity at carcasses was most influenced by the length of time the carcass was sampled, and the biological variables, temperature and prey weight . Nevertheless, diversity was relatively consistent across carcasses. We also identified six additional stalk-and-ambush carnivores weighing > 20 kg, that feed on prey larger than themselves, and are subordinate to other predators. Together with pumas, these seven felids may provide distinctive ecological functions through their disproportionate production of carrion and subsequent contributions to biodiversity. We urge conservation managers to increase support for these species, as a means of prioritizing resources to best ensure the persistence of carrion in natural systems. [ABSTRACT FROM AUTHOR]

Predator tourism is one strategy to improve tolerance for predators, and support biodiversity and ecosystem health. Torres del Paine National Park (TdP) – a UNESCO Biosphere Reserve in southern Chile - supports productive livestock industries and nascent puma tourism. We compared interviews conducted in the region prior to puma tourism, with results from interviews collected across 45 ranches post-puma tourism. We assessed rancher attitudes regarding pumas, puma-livestock conflict, puma tourism, and linked them with socio-ecological factors. Respondents who viewed pumas as a threat experienced higher livestock losses. Respondents who reported higher sheep losses were inclined to support the lethal removal of livestock-killing pumas, and to initiate a puma hunt, whereas respondents who supported puma tourism disagreed with hunting pumas. Using the Potential for Conflict Index, we found that participants exhibited the highest consensus on the benefit of puma tourism and the lowest consensus over lethal removal of pumas. Our results suggest predator tourism has increased tolerance for pumas but is creating new potential for conflict. Previous to puma tourism, ranchers were almost entirely negative about pumas and unanimously supported illegal puma hunting. Now, most believe that pumas are part of Patagonia's heritage. This divide was best explained by distance to TdP: ranches closer to TdP experienced greater losses to pumas but had neighbours that benefitted most from puma tourism. Therefore, we suggest that tourism revenues supplement community compensation insurance programs that reimburse rancher losses to pumas to mitigate the growing divide between those benefiting from pumas and those experiencing economic hardship. • Predator tourism has increased tolerance for pumas, but is creating new potential for conflict among ranchers. • Respondents who reported higher sheep losses were inclined to support the lethal control of livestock-killing pumas. • Respondents who supported puma tourism disagreed with hunting pumas. • Ranches closer to the National Park benefitted most from puma tourism but had neighbours that suffered the greatest costs. [ABSTRACT FROM AUTHOR]