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Populations of large terrestrial carnivores are in various stages of recovery worldwide and the question of whether there is compensation in mortality sources is relevant to conservation. Here, we show variation in Wisconsin wolf survival from 1979 to 2013 by jointly estimating the hazard of wolves’ radio-telemetry ending (endpoint) and endpoint cause. In previous analyses, wolves lost to radio-telemetry follow-up (collar loss) were censored from analysis, thereby assuming collar loss was unconfounded with mortality. Our approach allowed us to explicitly estimate hazard due to collar loss and did not require censoring these records from analysis. We found mean annual survival was 76% and mean annual causes of mortality were illegal killing (9.4%), natural and unknown causes (9.5%), and other human-caused mortality such as hunting, vehicle collisions and lethal control (5.1%). Illegal killing and natural mortality were highest during winter, causing wolf survival to decrease relative to summer. Mortality was highest during early recovery and lowest during a period of sustained population growth. Wolves again experienced higher risk of human-caused mortality relative to natural mortality as wolves expanded into areas with more human activity. We detected partial compensation in human- and natural-caused mortality since 2004 as the population saturated more available habitat. Prior to 2004, we detected additivity in mortality sources. Assessments of wolf survival and cause of mortality rates and the finding of partial compensation in mortality sources will inform wolf conservation and management efforts by identifying sources and sinks, finding areas of conservation need, and assessing management zone delineation. [ABSTRACT FROM AUTHOR]

World-wide concern over emerging vector-borne diseases has increased in recent years for both animal and human health. In the United Sates, concern about vector-borne diseases in canines has focused on Lyme disease, anaplasmosis, ehrlichiosis, and heartworm which infect domestic and wild canids. Of these diseases, Lyme and anaplasmosis are also frequently diagnosed in humans. Gray wolves (Canis lupus) recolonized Wisconsin in the 1970s, and we evaluated their temporal and geographic patterns of exposure to these four vector-borne diseases in Wisconsin as the population expanded between 1985 and 2011. A high proportion of the Wisconsin wolves were exposed to the agents that cause Lyme (65.6%) and anaplasma (47.7%), and a smaller proportion to ehrlichiosis (5.7%) and infected with heartworm (9.2%). Wolf exposure to tick borne diseases was consistently higher in older animals. Wolf exposure was markedly higher than domestic dog (Canis familiaris) exposure for all 4 disease agents during 2001–2013. We found a cluster of wolf exposure to Borrelia burgdorferi in northwestern Wisconsin, which overlaps human and domestic dog clusters for the same pathogen. In addition, wolf exposure to Lyme disease in Wisconsin has increased, corresponding with the increasing human incidence of Lyme disease in a similar time period. Despite generally high prevalence of exposure none of these diseases appear to have slowed the growth of the Wisconsin wolf population. [ABSTRACT FROM AUTHOR]

Examines the potential for natural wolf recovery in the northeastern United States via dispersal from southeastern Canada. Review of wolf dispersal and recolonization; Characteristics of potential source populations; Connectivity with potential wolf habitat.

We report the long-distance dispersal of a subadult male cougar (Puma concolor) from South Dakota to Milford, Connecticut, where it was struck and killed by a vehicle. Genetic samples suggest this animal originated from the Black Hills of South Dakota while isotope analysis and physical inspection revealed no evidence that the animal had been held in captivity. We detected this dispersing individual at 5 locations along its route (Minnesota, 3 times in Wisconsin and New York) with DNA from fecal or hair samples, and with multiple photographs from citizenrun camera traps (3 in Wisconsin and 1 in Michigan). The > 2,450 km straight-line distance (Black Hills of South Dakota to Connecticut) traveled by the cougar is the longest dispersal documented for the species. We propose a likely route of > 2,700 km over 2 years based on topography and our confirmed records. We suggest that this excessive movement was motivated by the absence of female cougars along the route. The documentation of such a rare biological event not only shows the great dispersal potential for male cougars but also highlights our ability to detect these movements with verifiable voucher DNA and photographic records. Evidence collected for this one animal, and complete absence of verifiable data from most anecdotal reports of cougars in the east, further confirms the lack of a breeding population in the region. [ABSTRACT FROM AUTHOR]

ABSTRACT We developed models and provide computer code to make carcass recovery data more useful to wildlife managers. With these tools, wildlife managers can understand the spatial, temporal (e.g., across time periods, seasons), and demographic patterns in mortality causes from carcass recovery datasets. From datasets of radio-collared and non-collared carcasses, managers can calculate the detection bias by mortality cause in a non-collared carcass dataset compared to a collared carcass dataset. As a first step, we provide a standard procedure to assign mortality causes to carcasses. We provide an example of these methods for radio-collared wolves ( n = 208) and non-collared wolves ( n = 668) found dead in Wisconsin (1979-2012). We analyzed differences in mortality cause relative to season, age and sex classes, wolf harvest zones, and recovery phase (1979-1995: initial recovery, 1996-2002: early growth, 2003-2012: late growth). Seasonally, illegal kills and natural deaths were proportionally higher in winter (Oct-Mar) than summer (Apr-Sep) for collared wolves, whereas vehicle strikes and legal kills were higher in summer than winter. Spatially, more illegally killed collared wolves occurred in eastern wolf harvest zones where wolves reestablished more slowly and in the central forest region where optimal habitat is isolated by agriculture. Natural mortalities of collared wolves (e.g., disease, intraspecific strife, or starvation) were highest in western wolf harvest zones where wolves established earlier and existed at higher densities. Calculating detection bias in the non-collared dataset revealed that more than half of the non-collared carcasses on the landscape are not found. The lowest detection probabilities for non-collared carcasses (0.113-0.176) occurred in winter for natural, illegal, and unknown mortality causes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Gray wolves ( Canis lupus ) have complex life-histories due, in part, to mating systems that depend on intra-group dominance hierarchies set within an inter-group (pack) social structure linked to philopatric territories. In addition to this spatially oriented social structure, mortality risk associated with interactions with humans varies spatially. We developed an individual-based spatially explicit (IBSE) model for the southern Lake Superior wolf population to better capture the life-history of wolves in a harvest model. Simulated wolves underwent an annual cycle of life-history stage-dependent mate-finding, dispersal, reproduction, and aging on a simulated landscape reflecting spatially explicit state and water boundaries, Indian reservation boundaries and ceded territories, wolf harvest zones, livestock depredation areas, and a spatial mortality risk surface. The latter 3 surfaces were linked to mortality events for simulated wolves. We assessed our IBSE model and conducted a sensitivity analysis of the most uncertain parameters with a categorical calibration of patterns observed at the individual, pack, population, and landscape level. We found that without recreational harvest, the Wisconsin wolf population grew to an average carrying capacity of 1242 wolves after 50 years and breeding pairs persisted for a mean 1.8 years. We simulated 6 recreational harvest scenarios with varying rates and timings of harvest and assessed effects on population size, pack sizes, age ratios, dispersal and immigration rates, and breeding pair tenures of the Wisconsin wolf population. The simulated harvest with rates of 14% which corresponded to the 2012 harvest in Wisconsin reduced the populations 4% in the first year of harvest and equilibrated to the pre-harvest population size after 20 years of harvest, on average. A 30% harvest rate across the simulation on average reduced the populations by 65% after 20 years with some populations going extinct before 100 years. In general, harvest increased the proportion of pups in the simulated populations and decreased breeding pair tenure. Targeted lethal control was more effective than harvest for reducing the number of wolves near known livestock depredation sites. Our model facilitates prediction of important population patterns that is simultaneously dependent on complexities associated with spatially structured life history and mortality. [ABSTRACT FROM AUTHOR]

Environmental hazards are distributed in nonrandom patterns; therefore, many biologists work to predict future hazard locations from the locations of past incidents. Predictive spatial models, or risk maps, promise early warning and targeted prevention of nonnative species invasion, disease spread, or wildlife damage. The prevention of hazards safeguards both humans and native biodiversity, especially in the case of conflicts with top predators. Top predators play essential ecological roles and maintain biodiversity, but they can also threaten human life and livelihood, which leads people to eradicate predator populations. In the present article, we present a risk map for gray wolf (Canis lupus) attacks on livestock in Wisconsin between 1999 and 2006 that correctly identified risk in 88% of subsequent attack sites from 2007 to 2009. More-open habitats farther from any forest and closer to wolf pack ranges were the riskiest for livestock. Prediction promotes prevention. We recommend that the next generation of risk mappers employ several criteria for model selection, validate model predictions against data not used in model construction before publication, and integrate predictors from organismal biology alongside human and environmental predictors. [ABSTRACT FROM AUTHOR]

Gray wolves (Canis lupus) in parts of the United States and Europe live in networks of disjunct populations, many of which are close to human settlement. Because wolf management goals include sustaining disjunct populations, it is important to ask what types of areas and protections are needed for population survival. To predict the effects of different levels of human-caused mortality, we created a simulation model for a disjunct wolf population living in a semi-wild landscape with abundant, well distributed prey. The landscape included a maximum of 16 territories divided into core and peripheral range. The mortality rate in the core range was 20%, whereas the mortality rate in peripheral range (40%) was higher because of human-caused deaths. We examined the relationship between the proportions of core and peripheral range and the 50-year occupancy of that range by wolf packs, given different assumptions about pup and dispersal mortality and immigration. Simulations showed that occupancy increased as the number of core sites increased, but curve location depended on parameter assumptions. With pup and dispersal mortality rates consistent with those for disease-free and legally protected populations, wolves saturated a 16-territory cluster with as few as two core sites, regardless of immigration rate. When populations had high pup or dispersal mortality, as few as two immigrants per year helped maintain high (>80%) site occupancy in clusters with four or more core sites. Small numbers of immigrants were also important for sustaining colonizing populations and buffering the negative effects of increased environmental variation. The simulations supported the claim that wolves can survive in disjunct populations provided that wolves can move between populations, human persecution is not excessive, and prey is abundant. [ABSTRACT FROM AUTHOR]

Managing risk requires an adequate understanding of risk-factors that influence the likelihood of a particular event occurring in time and space. Risk maps can be valuable tools for natural resource managers, allowing them to better understand spatial characteristics of risk. Risk maps can also support risk-avoidance efforts by identifying which areas are relatively riskier than others. However, risks, such as human-carnivore conflict, can be diverse, multi-faceted, and overlapping in space. Yet, efforts to describe risk typically focus on only one aspect of risk. We examined wolf complaints investigated in Wisconsin, USA for the period of 1999–2011. We described the spatial patterns of four types of wolf-human conflict: livestock depredation, depredation on hunting hounds, depredation on non-hound dogs, and human health and safety concerns (HHSC). Using predictive landscape models and discriminant functions analysis, we visualized the landscape of risk as a continuous surface of overlapping risks. Each type of conflict had its own unique landscape signature; however, the probability of any type of conflict increased closer to the center of wolf pack territories and with increased forest cover. Hunting hound depredations tended to occur in areas considered to be highly suitable wolf habitat, while livestock depredations occurred more regularly in marginal wolf habitat. HHSC and non-hound dog depredations were less predictable spatially but tended to occur in areas with low housing density adjacent to large wildland areas. Similar to other research evaluating the risk of human-carnivore conflict, our data suggests that human-carnivore conflict is most likely to occur where humans or human property and large carnivores co-occur. However, identifying areas of co-occurrence is only marginally valuable from a conservation standpoint and could be described using spatially-explicit human and carnivore data without complex analytical approaches. These results challenge our traditional understanding of risk and the standard approach used in describing risk. We suggest that a more comprehensive understanding of the risk of human-carnivore conflict can be achieved by examining the spatial and non-spatial factors influencing risk within areas of co-occurrence and by describing the landscape of risk as a continuous surface of multiple overlapping risks. Image 1 • Risk maps can support carnivore conservation efforts. • However, risk of human-carnivore conflict can be diverse, multi-faceted, and overlapping in space. • We described the landscape of risk for four types of wolf-human conflict as a continuous surface of overlapping risks. • Evaluating only one type of risk can lead to misunderstandings and reduced conservation utility. • We provide recommendations for future researchers to consider when describing risk for human-carnivore conflicts. [ABSTRACT FROM AUTHOR]

The article presents flawed analysis and unconvincing interpretation of impact of poaching on the conservation of carnivores. Topics discussed include analysis of hypothesis that culling will reduce poaching; impact of increasing availability of lethal depredation management on the reduction of illegal killing; and data on the same.

Rapid change in wildlife populations can challenge managers to promote species conservation while maintaining public support for wildlife. Wolf management during recolonization in Wisconsin, United States demonstrates the complexities of inconsistent management authority, public attitudes, and illegal killing of wolves. State management authority to control depredating wolves oscillated during a period of intense sociopolitical conflict over wolf status under the federal Endangered Species Act. We demonstrate that swings in wolf status led to inconsistent management authority, declining local public support for wolves, and possibly the unintended backlash of more illegal kills and a legislatively mandated public wolf hunt. A new Wildlife Management Matrix illustrates an idealized relationship between lethal control options and perceptions of wildlife. Moderating the sociopolitical drivers of swings in policy over short periods is essential to allow wildlife managers greater flexibility in achieving species-specific goals. To our knowledge, this research provides the first demonstrated link between illegal wildlife killing and management authority under the Endangered Species Act, and suggests that illegal behavior may be moderated with responsible and effective wildlife management programs. We recommend states avoid prescriptive harvest legislation, and we suggest a more incremental shift from federal to state management authority. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that wolves are reducing local browse intensity by white-tailed deer, thus indirectly mitigating the biotic impoverishment of understorey plant communities in northern Wisconsin., To assess the potential for such a top-down trophic cascade response, we developed a spatially and temporally explicit model of wolf territory occupancy based on three decades of wolf monitoring data. Using a nested multiscale vegetation survey protocol, we compared the understorey plant communities of northern white cedar wetlands found in high wolf areas with control sites found in low wolf areas., We fit species-area curves for plant species grouped by vegetation growth form (based on their predicted response to release from herbivory, i.e. tree, seedling, shrub, forb, grass, sedge or fern) and duration of wolf territory occupancy., As predicted for a trophic cascade response, forb species richness at local scales (10 m2) was significantly higher in high wolf areas (high wolf areas: 10.7 ± 0.9, N = 16, low wolf areas: 7.5 ± 0.9, N = 16, P < 0.001), as was shrub species richness (high wolf areas: 4.4 ± 0.4, N = 16, low wolf areas: 3.2 ± 0.5, N = 16, P < 0.001). Also as predicted, percentage cover of ferns was lower in high wolf areas (high wolf areas: 6.2 ± 2.1, N = 16, low wolf areas: 11.6 ± 5.3, N = 16, P < 0.05)., Beta richness was similar between high and low wolf areas, supporting earlier assumptions that deer herbivory impacts plant species richness primarily at local scales. Sampling at multiple spatial scales revealed that changes in species richness were not consistent across scales nor among vegetation growth forms: forbs showed a stronger response at finer scales (1-100 m2), while shrubs showed a response across relatively broader scales (10-1000 m2)., Synthesis. Our results are consistent with hypothesized trophic effects on understorey plant communities triggered by a keystone predator recovering from regional extinction. In addition, we identified the response variables and spatial scales appropriate for detecting such differences in plant species composition. This study represents the first published evidence of a trophic cascade triggered by wolf recovery in the Great Lakes region. [ABSTRACT FROM AUTHOR]

Lethal control alone has not proven entirely effective in reducing gray wolf (Canis lupus) depredations in chronic problem areas. Opponents of lethal control argue that more emphasis should be placed on integrating nonlethal strategies into current management. However, few evaluations have tested the effectiveness of nonlethal options .We compared behavior patterns in terms of frequency and duration of bait station visits for 5 wolves fitted with shock collars to 5 control animals inhabiting wolf pack territories in northern Wisconsin during summers of 2003 and 2004. Shock collared wolves spent less time and made fewer visits to bait station zones than did control animals. During and after shocking, wolves shifted 0.7 km away from the bait station zone. Although active shocking did restrict wolf access, which could be useful in controlling wolf depredations during a limited time period, conditioning was not clearly demonstrated once shocking ceased. The effect of shock collar design and operation on long-term conditioning and shock-conditioned wolves on pack behavior needs further study. If long-term conditioning is possible, shock collars could be used by wildlife managers as a nonlethal wolf management method in chronic problem areas where lethal control has proven ineffective. [ABSTRACT FROM AUTHOR]

Managers of recovering wolf (Canis lupus) populations require knowledge regarding the potential impacts caused by the loss of territorial, breeding wolves when devising plans that aim to balance population goals with human concerns. Although ecologists have studied wolves extensively, we lack an understanding of this phenomenon as published records are sparse. Therefore, we pooled data (n = 134 cases) on 148 territorial breeding wolves (75 M and 73 F) from our research and published accounts to assess the impacts of breeder loss on wolf pup survival, reproduction, and territorial social groups. In 58 of 71 cases (84%), ≥1 pup survived, and the number or sex of remaining breeders (including multiple breeders) did not influence pup survival. Pups survived more frequently in groups of ≥6 wolves (90%) compared with smaller groups (68%). Auxiliary nonbreeders benefited pup survival, with pups surviving in 92% of cases where auxiliaries were present and 64% where they were absent. Logistic regression analysis indicated that the number of adult-sized wolves remaining after breeder loss, along with pup age, had the greatest influence on pup survival. Territorial wolves reproduced the following season in 47% of cases, and a greater proportion reproduced where one breeder had to be replaced (56%) versus cases where both breeders had to be replaced (9%). Group size was greater for wolves that reproduced the following season compared with those that did not reproduce. Large recolonizing (>75 wolves) and saturated wolf populations had similar times to breeder replacement and next reproduction, which was about half that for small recolonizing (≤75 wolves) populations. We found inverse relationships between recolonizing population size and time to breeder replacement (r = -0.37) and time to next reproduction (r = -0.36). Time to breeder replacement correlated strongly with time to next reproduction (r = 0.97).Wolf social groups dissolved and abandoned their territories subsequent to breeder loss in 38% of cases. Where groups dissolved, wolves reestablished territories in 53% of cases, and neighboring wolves usurped territories in an additional 21% of cases. Fewer groups dissolved where breeders remained (26%) versus cases where breeders were absent (85%). Group size after breeder loss was smaller where groups dissolved versus cases where groups did not dissolve. To minimize negative impacts, we recommend that managers of recolonizing wolf populations limit lethal control to solitary individuals or territorial pairs where possible, because selective removal of pack members can be difficult. When reproductive packs are to be managed, we recommend that managers only remove wolves from reproductive packs when pups are ≥6 months old and packs contain ≥6 members (including ≥3 ad-sized wolves). Ideally, such packs should be close to neighboring packs and occur within larger (≥75 wolves) recolonizing populations. [ABSTRACT FROM AUTHOR]

An accompanying article in this issue of the Bulletin (Mech 2006) purports to critique our past research. L. D. Mech attempts to show that our model of prospective, preferred gray wolf (Canis lupus) habitat (Mladenoff et al. 1995, 1997, 1999, Mladenoff and Sickley 1998) has been incorrect. We first state clearly that we are not opposed to the re-assessment of our work based on new data. However we believe the Mech paper contains both serious conceptual and methodological flaws that render its conclusions invalid. Our own analysis, based on logic and current techniques (Mladenoff et al. 2005), shows that the model has behaved according to our predictions and continues to successfully predict wolf recolonization in Wisconsin, USA, over more than 25 years. However, the serious flaws of Mech (2006) alone show that he is incorrect in his putative critique of our work. [ABSTRACT FROM AUTHOR]

We examined the use of dog shock collars on 2 different wolves (Canis lupus) over a 4-year period to assess whether this system could be used to reduce wolf depredation on livestock. In 1998 we used human-induced shock and determined that the shock collar could keep a depredating wolf off a farm while maintaining normal den- and rendezvous-site attendance, but it did not seem to have a long-term effect on the wolf's behavior. In 1999 we captured a wolf prior to any depredations and used a command center with a beeper that remotely shocked the wolf while also providing aversive stimuli; no depredations occurred in 1999. We used the beeper unit alone in 2000, when only 2 calves were killed. A second wolf was captured in 2001 after depredations began, and although it was kept off the farm, other pack members caused further depredation and were removed from the farm. It appears that in some situations shock collars with a command center and beeper device may be useful for reducing wolf depredations, but more research is needed. [ABSTRACT FROM AUTHOR]

Many carnivore populations escaped extinction during the twentieth century as a result of legal protections, habitat restoration, and changes in public attitudes. However, encounters between carnivores, livestock, and humans are increasing in some areas, raising concerns about the costs of carnivore conservation. We present a method to predict sites of human-carnivore conflicts regionally, using as an example the mixed forest-agriculture landscapes of Wisconsin and Minnesota (U.S.A.). We used a matched-pair analysis of 17 landscape variables in a geographic information system to discriminate affected areas from unaffected areas at two spatial scales (townships and farms). Wolves (Canis lupus ) selectively preyed on livestock in townships with high proportions of pasture and high densities of deer (Odocoileus virginianus ) combined with low proportions of crop lands, coniferous forest, herbaceous wetlands, and open water. These variables plus road density and farm size also appeared to predict risk for individual farms when we considered Minnesota alone. In Wisconsin only, farm size, crop lands, and road density were associated with the risk of wolf attack on livestock. At the level of townships, we generated two state-wide maps to predict the extent and location of future predation on livestock. Our approach can be applied wherever spatial data are available on sites of conflict between wildlife and humans. [ABSTRACT FROM AUTHOR]

Presents a study that documented complaints about wolf depredation in Wisconsin between 1976 to 2000. Analysis of the the temporal and geographic patterns of wolf depredation; Identification of the depredating wolves; Examination of compensation and control operations for wolf depredation.