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Summary Human‐caused harassment and mortality (e.g. hunting) affects many aspects of wildlife population dynamics and social structure. Little is known, however, about the social and physiological effects of hunting, which might provide valuable insights into the mechanisms by which wildlife respond to human‐caused mortality. To investigate physiological consequences of hunting, we measured stress and reproductive hormones in hair, which reflect endocrine activity during hair growth. Applying this novel approach, we compared steroid hormone levels in hair of wolves (Canis lupus) living in Canada's tundra–taiga (n = 103) that experience heavy rates of hunting with those in the northern boreal forest (n = 45) where hunting pressure is substantially lower. The hair samples revealed that progesterone was higher in tundra–taiga wolves, possibly reflecting increased reproductive effort and social disruption in response to human‐related mortality. Tundra–taiga wolves also had higher testosterone and cortisol levels, which may reflect social instability. To control for habitat differences, we also measured cortisol in an out‐group of boreal forest wolves (n = 30) that were killed as part of a control programme. Cortisol was higher in the boreal out‐group than in our study population from the northern boreal forest. Overall, our findings support the social and physiological consequences of human‐caused mortality. Long‐term implications of altered physiological responses should be considered in management and conservations strategies. Lay Summary

Large carnivores are negotiating increasingly developed landscapes, but little is known about how such behavioral plasticity influences their demographic rates and population trends. Some investigators have suggested that the ability of carnivores to behaviorally adapt to human development will enable their persistence, and yet, others have suggested that such landscapes are likely to serve as population sinks or ecological traps. To understand how plasticity in black bear (Ursus americanus) use of residential development influences their population dynamics, we conducted a 6‐yr study near Durango, Colorado, USA. Using space‐use data on individual bears, we examined the influence of use of residential development on annual measures of bear body fat, cub productivity, cub survival, and adult female survival, after accounting for variation in natural food availability and individual attributes (e.g., age). We then used our field‐based vital rate estimates to parameterize a matrix model that simulated asymptotic population growth for bears using residential development to different degrees. We found that bear use of residential development was highly variable within and across years, with bears increasing their foraging within development when natural foods were scarce. Increased bear use of development was associated with increased body fat and cub productivity, but reduced cub and adult survival. When these effects were simultaneously incorporated into a matrix model, we found that the population was projected to decline as bear use of development increased, given that the costs of reduced survival outweighed the benefits of enhanced productivity. Our results provide a mechanistic understanding of how black bear use of residential development exerts opposing effects on different bear fitness traits and a negative effect on population growth, with the magnitude of those effects mediated by variation in environmental conditions. They also highlight the importance of monitoring bear population dynamics, particularly as shifts in bear behavior are likely to drive increases in human–bear conflicts and the perception of growing bear populations. Finally, our work emphasizes the need to consider the demographic viability of large carnivore populations when promoting the coexistence of people and carnivores on shared landscapes.

Gray literature and data from unpublished sources can provide important scientific information that has not been published scientifically. The Persian leopard (hereafter leopard) Panthera pardus saxicolor is classed as endangered on the Red List of the International Union for Conservation of Nature and also is one of the least‐studied subspecies of leopard. It occurs in the Caucasus and Central and Southwest Asia. Iran contains more than 75% of the leopard's extant range, and the leopard population in this country serves as a source for neighboring countries. In this study, we determined the distribution and human‐caused mortality of leopards in Iran, by reviewing unpublished data and Farsi gray literature (which includes government reports) between 1 January 2010 and 30 December 2018. We created the most recent distribution map of the leopard in Iran. Our data display that human‐caused mortality of leopard in Iran mostly includes poaching and intentional poisoning, and roadkill. We created the most recent distribution map of the Persian leopards in Iran. We then identified poaching and intentional poisoning, and roadkill as the most important causes of leopard mortality in Iran.

Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP). We replicated their analyses considering only those years in which field monitoring was consistent, and we considered the effect of annual variation in recruitment on wolf population growth. Rather than assuming constant rates, we used model selection methods to evaluate and incorporate models of factors driving recruitment and human‐caused mortality rates in wolf populations in the Northern Rocky Mountains. Using data from 27 area‐years of intensive wolf monitoring, we show that variation in both recruitment and human‐caused mortality affect annual wolf population growth rates and that human‐caused mortality rates have increased with the sizes of wolf populations. We document that recruitment rates have decreased over time, and we speculate that rates have decreased with increasing population sizes and/or that the ability of current field resources to document recruitment rates has recently become less successful as the number of wolves in the region has increased. Estimates of positive wolf population growth in Montana from our top models are consistent with field observations and estimates previously made by MFWP for 2008–2010, whereas the predictions for declining wolf populations of Creel and Rotella (2010) are not. Familiarity with limitations of raw data, obtained first‐hand or through consultation with scientists who collected the data, helps generate more reliable inferences and conclusions in analyses of publicly available datasets. Additionally, development of efficient monitoring methods for wolves is a pressing need, so that analyses such as ours will be possible in future years when fewer resources will be available for monitoring. © 2011 The Wildlife Society.

Under the Endangered Species Act, documenting recovery and federally mandated population levels of wolves (Canis lupus) in the Northern Rocky Mountains (NRM) requires monitoring wolf packs that successfully recruit young. United States Fish and Wildlife Service regulations define successful breeding pairs as packs estimated to contain an adult male and female, accompanied by ≥2 pups on 31 December of a given year. Monitoring successful breeding pairs will become more difficult following proposed delisting of NRM wolves; alternatives to historically intensive methods, appropriate to the different ecological and regulatory context following delisting, are required. Because pack size is easier to monitor than pack composition, we estimated probability a pack would contain a successful breeding pair based on its size for wolf populations inhabiting 6 areas in the NRM. We also evaluated the extent to which differences in demography of wolves and levels of human-caused mortality among the areas influenced the probability of packs of different sizes would contain successful breeding pairs. Probability curves differed among analysis areas, depending primarily on levels of human-caused mortality, secondarily on annual population growth rate, and little on annual population density. Probabilities that packs contained successful breeding pairs were more uniformly distributed across pack sizes in areas with low levels of human mortality and stable populations. Large packs in areas with high levels of human-caused mortality and high annual growth rates had relatively high probabilities of containing breeding pairs whereas those for small packs were relatively low. Our approach can be used by managers to estimate number of successful breeding pairs in a population where number of packs and their sizes are known. Following delisting of NRM wolves, human-caused mortality is likely to increase, resulting in more small packs with low probabilities of containing breeding pairs. Differing contributions of packs to wolf population growth based on their size suggests monitoring successful breeding pairs will provide more accurate insights into population dynamics of wolves than will monitoring number of packs or individuals only.

Predators and their protection are controversial worldwide. Gray wolves, Canis lupus , lost U.S. federal protection (delisting) and the State of Wisconsin began lethal management first among all states and tribes that regained authority over wolves. Here we evaluated the initial success of reaching the state’s explicit objective, “…to allow for a sustainable harvest that neither increases nor decreases the state’s wolf population…” We used official state figures for hunter-killed wolves, population estimates from April 2017–2020, and the latest peer-reviewed model of individual wolf survival to estimate additional deaths resulting from federal delisting. More than half of the additional deaths were predicted to be cryptic poaching under the assumption that this period resembled past periods of liberalized wolf-killing in Wisconsin. We used a precautionary approach to construct three conservative scenarios to predict the current status of this wolf population and a minimum estimate of population decline since April 2020. From our scenarios that vary in growth rates and additional mortality estimates, we expect a maximum of 695–751 wolves to be alive in Wisconsin by 15 April 2021, a minimum 27–33% decline in the preceding 12 months. This contradicts the state expectation of no change in the population size. We draw a conclusion about the adequacy of regulatory mechanisms under state control of wolves and discuss the particular governance conditions met in Wisconsin. We recommend greater rigor and independent review of the science used by agencies to plan wolf hunting quotas and methods. We recommend clearer division of duties between state wildlife agencies, legislatures, and courts. We recommend federal governments reconsider the practice of sudden deregulation of wolf management and instead recommend they consider protecting predators as non-game or transition more slowly to subnational authority, to avoid the need for emergency relisting.

Managing the number of grizzly bear ( Ursus arctos ) mortalities to a sustainable level is fundamental to bear conservation. All known grizzly bear deaths are recorded by management agencies but the number of human-caused grizzly bear deaths that are not recorded is generally unknown, causing considerable uncertainty in the total number of mortalities. Here, we compare the number of bears killed legally by hunters to the number killed by people for all other reasons, for bears wearing functioning radiocollars and for uncollared bears recorded in the British Columbia (BC) government mortality database for the Flathead Valley in southeast BC. Between 1980 and 2016, permitted hunters killed 10 collared bears and 12 (9 known, 3 suspected) were killed by people for other reasons. This ratio differed ( p < 0.0001) from the uncollared bears in the government database where 71 were killed by hunters while only 10 were killed for other reasons. We estimate that 88% (95% CI; 67–96%) of the human-caused mortalities that were not by permitted hunters were unreported. The study area may have low reporting rates because it is >40 km on a gravel road from a Conservation Officer office, so reporting is difficult and there are no human residences so there is little concern of a neighbor contacting an officer. Our results are likely indicative of other places that are road-accessed but far from settlements. We discuss the implications of sampling individuals for collaring and the possible implications of wearing a collar on the animal’s fate.

Mortality resulting from human—wildlife conflicts affects wildlife populations globally. Since 2004, we have been researching conservation issues and implementing a comprehensive program to reduce human—bear conflicts (Ursus spp.; HBC) for 3 small, fragmented, and threatened grizzly bear (U. arctos) populations in the trans-border region of southwest Canada and northwest USA. We explored the temporal and spatial patterns of conflict mortality and found that HBC contributed significantly to the threatened status of these populations by causing decline, fragmentation, and decreased habitat effectiveness. Our program to reduce HBCs primarily included strategic private lands purchased to reduce human density in wildlife corridors, the reduction of bear attractants where human settlement and agriculture exists, and the nonlethal management of conflict bears. Attractant management strategies encompassed public education, cost-share electric fencing, bear-resistant garbage containers, and deadstock containment. We taught bear safety courses and bear spray training to increase tolerance and give people tools to avoid negative encounters with bears. We radio-collared and used nonlethal management on potential conflict bears and have a ~75% success rate in that the bear was alive and out of conflict situations over the life of the radiocollar. We identified important backcountry grizzly bear foraging habitat for motorized access control to reduce conflict and mortality and provide habitat security to reproductive females. Ongoing monitoring has demonstrated that our comprehensive HBC program has resulted in a significant reduction in human-caused mortality, increased inter-population connectivity, and improved habitat effectiveness. Several challenges remain, however, including an increase in the numbers of young grizzly bears living adjacent to agricultural areas. Herein we discuss strategies for how to integrate conservation vision into future HBC reduction programs.

Human intervention is the main cause of the decline of the Critically Endangered European mink Mustela lutreola. In this study we analysed the main causes of direct human-caused mortality of the species in Spain. A total of 47 mortality records were obtained for the period 1950–1989, and 145 for 1990–2008. There was temporal variation in the cause of death, with trapping and shooting being the most common causes of mortality in 1950–1989 and road-kills in 1990–2008. In the case of road-kills there was variation related to road type. Males were more affected by road-kills than females, especially during the mating season when they range more widely. Our results indicate that there has been a change in human social behaviour and in people's awareness of the species, with a reduction in European mink captured and shot but an increase in mortality on roads.