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Wolf (Canis lupus) predation on livestock and management methods used to mitigate conflicts are highly controversial and scrutinized especially where wolf populations are recovering. Wolves are commonly removed from a local area in attempts to reduce further depredations, but the effectiveness of such management actions is poorly understood. We compared the effects of 3 management responses to livestock depredation by wolf packs in Montana, Idaho, and Wyoming: no removal, partial pack removal, and full pack removal. We examined the effectiveness of each management response in reducing further depredations using a conditional recurrent event model. From 1989 to 2008, we documented 967 depredations by 156 packs: 228 on sheep and 739 on cattle and other stock. Median time between recurrent depredations was 19 days following no removal (n = 593), 64 days following partial pack removal (n = 326), and 730 days following full pack removal (n = 48; recurring depredations were made by the next pack to occupy the territory). Compared to no removal, full pack removal reduced the occurrence of subsequent depredations by 79% (hazard ratio [HR] = 0.21, P

The absence of top-level predators in many natural areas in North America has resulted in overabundant ungulate populations, cascading negative impacts on plant communities, and the loss of biodiversity and ecosystem processes. Meanwhile, distinct population segments of the gray wolf (Canis lupus) have been removed from the list of endangered and threatened species, implying an end to wolf recovery and reintroductions. We propose another paradigm for wolf conservation, one that emphasizes ecosystem recovery instead of wolf recovery. Improvements in technology, an enhanced understanding of the ecological role of wolves, lessons from other countries, and changing public attitudes provide a new context and opportunity for wolf conservation and ecosystem restoration. Under this new paradigm, small populations of wolves, even single packs, could be restored to relatively small natural areas for purposes of ecosystem restoration and stewardship. We acknowledge the complications and challenges involved in such a...

Minimizing risk of predation from multiple predators can be difficult, particularly when the risk effects of one predator species may influence vulnerability to a second predator species. We decomposed spatial risk of predation in a 2-predator, 2-prey system into relative risk of encounter and, given an encounter, conditional relative risk of being killed. Then, we generated spatially explicit functions of total risk of predation for each prey species (elk [Cervus elaphus] and mule deer [Odocoileus hemionus]) by combining risks of encounter and kill. For both mule deer and elk, topographic and vegetation type effects, along with resource selection by their primary predator (cougars [Puma concolor] and wolves [Canis lupus], respectively), strongly influenced risk of encounter. Following an encounter, topographic and vegetation type effects altered the risk of predation for both ungulates. For mule deer, risk of direct predation was largely a function of cougar resource selection. However, for elk, risk of direct predation was not only a function of wolf occurrence, but also of habitat attributes that increased elk vulnerability to predation following an encounter. Our analysis of stage-based (i.e., encounter and kill) predation indicates that the risk effect of elk shifting to structurally complex habitat may ameliorate risk of direct predation by wolves but exacerbate risk of direct predation by cougars. Information on spatiotemporal patterns of predation will be become increasingly important as state agencies in the western United States face pressure to integrate predator and prey management.

Numerous studies have documented how prey may use antipredator strategies to reduce the risk of predation from a single predator. However, when a recolonizing predator enters an already complex predator–prey system, specific antipredator behaviors may conflict and avoidance of one predator may enhance vulnerability to another. We studied the patterns of prey selection by recolonizing wolves (Canis lupus) and cougars (Puma concolor) in response to prey resource selection in the northern Madison Range, Montana, USA. Elk (Cervus elaphus) were the primary prey for wolves, and mule deer (Odocoileus hemionus) were the primary prey for cougars, but elk made up an increasingly greater proportion of cougar kills annually. Although both predators preyed disproportionately on male elk, wolves were most likely to prey on males in poor physical condition. Although we found that the predators partitioned hunting habitats, structural complexity at wolf kill sites increased over time, whereas complexity of couga...

Mexican desert bighorn sheep (Ovis canadensis mexicana) populations have declined since the 1980s, and restoration efforts are necessary to establish viable populations. Mexican desert bighorn sheep were translocated to the Fra Cristobal Mountains of south-central New Mexico in 1995. We described seasonal habitats used by female desert bighorn sheep by comparing characteristics of radiolocations with random locations within their home range. We developed a geographic information system to derive aspect, distance to steep slopes, elevation, slope, substrate associations, terrain ruggedness, and visibility. We developed seasonal logistic regression models that incorporated distance to 60% slope patches, ruggedness, slope, substrate, and visibility. Habitat characteristics at bighorn sheep locations were similar among seasons. Bighorn sheep locations were on steeper and more rugged terrain, closer to topography with a 60% slope, and had lower visibility than random locations. Based on our description of habitat selection by sheep, managers in New Mexico may need to reassess the amount of escape habitat in restoration areas to prioritize translocations and plan to manage predators.

Weights, hematology, and serum profiles of white-tailed does in the central Superior National Forest of northeastern Minnesota were examined year-around to determine seasonal patterns of nutritional condition and metabolism. Deer were initially captured by Clover trap or rocket net. Between 15 February 1989 and 23 January 1990, we recaptured 12 adult (> 1.5 years) female deer 1–9 times each (a total of 59 recaptures) using a radio-controlled capture collar. Monthly weights of deer exhibited a cyclic seasonal pattern. Mean weight declined 22% from February to an annual minimum during May, then steadily increased 45% to a maximum in October. Seasonal patterns were most evident for hemoglobin concentration, red blood cells, packed cell volume, serum total protein, urea nitrogen, creatinine, the urea N to creatinine ratio, triiodothyronine, cortisol, and potassium. Wide seasonal variations of these characteristics were indicative of shifts in the deer's metabolic physiology. Although seasonal metabolic shifts are partially attributable to an endogenous rhythm, the intensity of their expression was most likely affected by nutritional changes and concomitant alterations of body condition. Annual changes in seasonal trends of blood characteristics may be useful in investigating nutritional effects of specific environmental and demographic factors. We compare our findings with those reported for deer on ranges farther south.

We tested the reliability and predictive capabilities of the activity meter in the new Wildlink Data Acquisition and Recapture System by comparing activity counts with concurrent observations of captive wolf (Canis lupus) and free-ranging white-tailed deer (Odocoileus virginianus) activity. The Wildlink system stores activity data in a computer within a radio collar with which a biologist can communicate. Three levels of activity could be detected. The Wildlink system provided greater activity discrimination and was more reliable, adaptable, and efficient and was easier to use than conventional telemetry activity systems. The Wildlink system could be highly useful for determining wildlife energy budgets.

Introduction Large carnivores operate over large spatial scales and affect and are affected by multiple ecosystem processes (e.g., predation, migration, climate, fire, etc.). Thus carnivore ecologists must deal with expansive areas and multiple scales and disciplines. For this reason, studies of top carnivores have played a significant role in fostering ecosystem approaches among managers and researchers (Minta et al. 1999). Specifically, wolves ( Canis lupus ), cougars ( Felis concolor ), and bears ( Ursus spp.) have become important symbols for conservation and ecosystem management. Recent research has examined multiple large carnivores (Kunkel et al. 1999, Carroll et al. 2001) and multiple ecosystems in regional conservation networks (Soule and Terborgh 1999). Conservation perspectives resulting from such work can help build strategies to protect appreciable amounts of native biological diversity (Noss and Cooperrider 1994, Paquet and Hackman 1995, Soule and Terborgh 1999). Conservation strategies that focus on charismatic animals such as large carnivores have additional advantages because such a focus motivates organizations and the general public. Even though large carnivores often are grouped for management and share many traits, some important differences affect their resiliency (Weaver et al. 1996). The most obvious split occurs between the obligatory predators (cougars, wolves, and jaguars ( Panthera onca )) and the omnivorous facultative predators (bears). Cougars, wolves, and jaguars have higher dispersal capabilities and higher reproductive rates than bears. Wolves are social; cougars, jaguars, and bears are solitary.