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Few topics in wildlife conservation are as controversial, emotive, or command as much public and political attention, as trophy hunting. International discourses regarding trophy hunting are characterised by radically contradictory assertions, ranging from claims that trophy hunting is a humane and socially acceptable wildlife management tool which benefits more animals than it kills, to claims that it is cruel, socially unacceptable, and drives species to extinction. So, which is it? We argue that using a single, blanket term “trophy hunting” obscures substantial and important variation in how and why people pay to hunt and keep trophies. Consequently, polarised disagreements over whether “trophy hunting” is good or bad, acceptable or unacceptable, beneficial or harmful, conflate arguments about fundamentally different activities. We urge conservation scientists and practitioners, politicians, journalists, and advocates on all sides to communicate more clearly and carefully about which specific hunting activities they believe are right or wrong, beneficial, or harmful, acceptable or unacceptable, to whom, and for what reasons.

Many studies have shown that behavioral responses to the risk posed by predators can carry costs for prey by reducing fecundity or survival, with consequent effects on population dynamics. Responses to risk include increased vigilance and reduced foraging, movement to safe habitats, increases or decreases in group size, and changes in patterns of movement. While we know that prey can detect and respond to both long term (LT) and short term (ST) variation in risk, field studies have only recently begun to consider how these responses might differ. Here, we hypothesize that prey movement patterns should respond differently to cues of LT and ST variation in risk. Specifically, cues of elevated LT risk might lead to decreased movement to improve the assessment of ST risk, while elevated ST risk might favor increased movement to reduce the proximity or duration of risks that are already assessed to be acute. We further hypothesize that decreases in movement are likely to be a general response to LT risk, while responses to ST risk are likely to vary in a manner that depends on the type of predator. In Liuwa Plain National Park, we found that wildebeest movements responded to the local intensity of predator use (LT risk), after controlling for other seasonal, diurnal and bottom-up effects. Speed decreased considerably and turning angles increased considerably, combining to markedly decrease linear movements. In contrast, immediate encounters with predators (ST risk) typically provoked fast, linear flight, and this effect was stronger for encounters with coursing predators. The effect of long term risk was to cause wildebeest to move more slowly and less linearly, i.e. to slow down and turn around, as part of a suite of behavioral responses, which also includes increased vigilance, that promote cautious assessment of ST risks when in locations with high levels of LT risk. This result has broad implications of understanding the influence of predation risk on foraging patterns of ungulates as this relationship is much more complex than simple avoidance of areas of ‘high risk’.

Jaguars (Panthera onca), like other apex predators, are highly susceptible to habitat loss and fragmentation given their low demographic potential and large habitat area requirements. Across their range, the Pantanal is considered critical for the jaguar's long-term conservation. Here we provide the first multi-scale path selection function model for jaguars, and the first empirically-based movement model covering the entire Pantanal ecosystem. Out of eight investigated variables, six were related to jaguar habitat use in the Pantanal: terrain roughness, human population density, grassland, percentage of tree cover, flooded habitats and shrubland. The results of scale optimization revealed that jaguars responded primarily to landscape variables at broad scales (32 km) of habitat availability, with only one variable (grassland) influencing jaguar path selection at a finer scale (4 km). Jaguar habitat use was positively associated with flooded habitats and densely forested areas and negatively associated with grassland, terrain roughness, and human population density, with the latter having the strongest negative effect on jaguar movement. The prediction map suggested that only 9.3% of the total suitable jaguar habitat in Pantanal is protected by Conservation Units. Among the most suitable areas, the largest continuous habitats were located in the northwestern portions of the Pantanal, which corresponds to the interfluvial areas between Corixo Grande and Cuiaba rivers. Our results suggested that the implementation of already proposed North Pantanal Conservation Unit Mosaic in this area would be highly valuable for jaguar conservation. This study provides a foundation for future research to delineate and prioritize core areas and corridors for jaguars in the region.

Apex carnivores are wide‐ranging, low‐density, hard to detect, and declining throughout most of their range, making population monitoring both critical and challenging. Rapid and inexpensive index calibration survey (ICS) methods have been developed to monitor large African carnivores. ICS methods assume constant detection probability and a predictable relationship between the index and the actual population of interest. The precision and utility of the resulting estimates from ICS methods have been questioned. We assessed the performance of one ICS method for large carnivores—track counts—with data from two long‐term studies of African lion populations. We conducted Monte Carlo simulation of intersections between transects (road segments) and lion movement paths (from GPS collar data) at varying survey intensities. Then, using the track count method we estimated population size and its confidence limits. We found that estimates either overstate precision or are too imprecise to be meaningful. Overstated precision stemmed from discarding the variance from population estimates when developing the method and from treating the conversion from tracks counts to population density as a back‐transformation, rather than applying the equation for the variance of a linear function. To effectively assess the status of species, the IUCN has set guidelines, and these should be integrated in survey designs. We propose reporting the half relative confidence interval width (HRCIW) as an easily calculable and interpretable measure of precision. We show that track counts do not adhere to IUCN criteria, and we argue that ICS methods for wide‐ranging low‐density species are unlikely to meet those criteria. Established, intensive methods lead to precise estimates, but some new approaches, like short, intensive, (spatial) capture–mark–recapture (CMR/SECR) studies, aided by camera trapping and/or genetic identification of individuals, hold promise. A handbook of best practices in monitoring populations of apex carnivores is strongly recommended., We tested and analyzed a popular rapid and cheap track survey method for large carnivores with randomly generated transects and empirical data on lion movements. We found that these methods are not able to reliably detect changes in populations of large carnivores often not even including the true population size in its confidence interval. We argue that the power of population estimates should meet criteria, preferably the IUCN guidelines, to detect population trends.

Allocating resources to growth and reproduction requires grazers to invest time in foraging, but foraging promotes dental senescence and constrains expression of proactive antipredator behaviors such as vigilance. We explored the relationship between carnivore prey selection and prey foraging effort using incisors collected from the kills of coursing and stalking carnivores. We predicted that prey investing less effort in foraging would be killed more frequently by coursers, predators that often exploit physical deficiencies. However, such prey could expect delayed dental senescence. We predicted that individuals investing more effort in foraging would be killed more frequently by stalkers, predators that often exploit behavioral vulnerabilities. Further these prey could expect earlier dental senescence. We tested these predictions by comparing variation in age‐corrected tooth wear, a proxy of cumulative foraging effort, in adult (3.4–11.9 years) wildebeest killed by coursing and stalking carnivores. Predator type was a strong predictor of age‐corrected tooth wear within each gender. We found greater foraging effort and earlier expected dental senescence, equivalent to 2.6 additional years of foraging, in female wildebeest killed by stalkers than in females killed by coursers. However, male wildebeest showed the opposite pattern with the equivalent of 2.4 years of additional tooth wear in males killed by coursers as compared to those killed by stalkers. Sex‐specific variation in the effects of foraging effort on vulnerability was unexpected and suggests that behavioral and physical aspects of vulnerability may not be subject to the same selective pressures across genders in multipredator landscapes.

Within a large carnivore guild, subordinate competitors (African wild dog, Lycaon pictus, and cheetah, Acinonyx jubatus) might reduce the limiting effects of dominant competitors (lion, Panthera leo, and spotted hyena, Crocuta crocuta) by avoiding them in space, in time, or through patterns of prey selection. Understanding how these competitors cope with one other can inform strategies for their conservation. We tested how mechanisms of niche partitioning promote coexistence by quantifying patterns of prey selection and the use of space and time by all members of the large carnivore guild within Liuwa Plain National Park in western Zambia. Lions and hyenas specialized on wildebeest, whereas wild dogs and cheetahs selected broader diets including smaller and less abundant prey. Spatially, cheetahs showed no detectable avoidance of areas heavily used by dominant competitors, but wild dogs avoided areas heavily used by lions. Temporally, the proportion of kills by lions and hyenas did not detectably differ across four time periods (day, crepuscular, early night, and late night), but wild dogs and especially cheetahs concentrated on time windows that avoided nighttime hunting by lions and hyenas. Our results provide new insight into the conditions under which partitioning may not allow for coexistence for one subordinate species, the African wild dog, while it does for cheetah. Because of differences in responses to dominant competitors, African wild dogs may be more prone to competitive exclusion (local extirpation), particularly in open, uniform ecosystems with simple (often wildebeest dominated) prey communities, where spatial avoidance is difficult.

If access to food is affected by the risk of predation, then the number of individuals killed by predators is an incomplete measure of the limiting effect of predation. Nonetheless, it is often assumed that the costs of antipredator responses (risk effects) are either small enough to be ignored or positively correlated with direct predation, and thus unlikely to alter inferences based on predation rates. These assumptions are rarely tested. Here we studied five large carnivores and ten prey species in three Zambian ecosystems to test relationships between direct predation, antipredator vigilance and trade-offs with foraging. The presence of a predator caused vigilance to increase by a factor of 2.4, with substantial variation among prey species in the strength of this response. This was associated with a 28% decrease in the proportion of individuals foraging, a trade-off that was consistent across species. We detected no correlation between direct predation and the strength of antipredator responses, which undermines the gambit of ignoring risk effects. The strength of antipredator responses was uncorrelated with broad attributes of predators and environments, but was correlated with attributes of prey. Responses were stronger for small species and for browsers/mixed feeders relative to grazers. It has previously been noted that small ungulates face higher rates of direct predation. Building on this inference, our results suggest that carnivore loss/restoration will also have stronger behaviorally-mediated effects on small ungulates, particularly browsers and mixed feeders. If such species increase their representation where carnivores are depleted, then cascading effects on vegetation would be expected.

Interspecific competition between large carnivores is not well understood due to the complexity of carnivore guild dynamics and the array of ecological and human factors affecting them. The loss of a carnivore guild's dominant species can therefore provide considerable insights. We evaluated spotted hyaena density and demography from Zambia's Liuwa Plain National Park, a recovering ecosystem where the hyaena's main competitor, the African lion, was severely reduced to 3–5 animals. Using data from 233 individuals in five clans and mark-resight robust design models we estimated population size, density, age and sex-specific annual survival rates for the hyaena population from 2010 to 2013 and tested for the effect of human settlements, prey density, competition with lions and hyaena clan size on mean hyaena survival. We estimated a minimum density of 0.13 hyaenas/km2 and maximum density of 0.52 hyaenas/km2. Density fluctuated with seasonal migrations of the main prey species, the blue wildebeest. Mean annual survival across all age classes was 0.93 (95%CI: 0.79–0.99). With high survival rates across all sex and age classes, we found no detectable effects of ecological or anthropogenic factors on survival. These results suggest that the combination of abundant prey, weak human-carnivore conflict, and weak competition from lions provide very favourable conditions for hyaena survival. Additional investigations of hyaena demography concurrent with lion population recovery efforts can provide considerable insights into the dynamics of carnivore competition and predation in African savannahs and the human and ecological factors affecting them.

Large carnivores are in rapid global decline, with a broad array of consequences for the ecosystems they inhabit. To efficiently detect and address these declines requires unbiased and precise demographic data. Unfortunately, the characteristics that make large carnivores extinction-prone also pose serious challenges to obtaining these data. Rapid survey methods exist, but provide only relative measures of abundance, cannot detect declines before they become large, and provide little or no information about the causes of decline. African lions (Panthera leo) are declining throughout their range, making accurate monitoring of remaining populations urgent. We provide statistically rigorous estimates of population size, trends, survival rate and age–sex structure from Zambia’s South Luangwa lion population from 2008 to 2012, just prior to cessation of hunting in 2013. Mark-recapture models fit to data from intensive monitoring of 210 individual lions in 18 prides and 14 male coalitions indicated a declining population, low recruitment, low sub-adult and adult male survival, depletion of adult males, and a senescing adult female population. Trophy hunting was the leading cause of death, with 46 males harvested. Based on these data we recommend continuing the hunting ban at least to 2016 to allow recovery, with substantially reduced quotas, age-limits, and effective trophy monitoring mandated thereafter should hunting resume. Similar data from intensive monitoring of key Zambian lion populations is required to evaluate effects of the hunting ban and provide management guidance. Effectively integrating intensive long-term monitoring and rapid survey methods should be a priority for future management and monitoring of carnivore species.

Wire snare poaching is widespread in Africa yet snaring trends, patterns and the impacts of by-catch on non-target threatened species such as elephant (Loxodonta africana), lion (Panthera leo) and African wild dog (Lycaon pictus) are poorly understood. We conducted retrospective analyses of data from 1038 anti-poaching patrols conducted in Zambia’s Luangwa valley from December 2005 to November 2010, to evaluate snaring dynamics and the effect of season, patrol size and length on snare detection. We also assessed impacts of by-catch on elephant, lion, and wild dog populations critical to the area’s wildlife tourism-based economy. Snaring mortality increased overall elephant poaching offtake by 32%. Approximately 11.5% of the adult and subadult lion population and 20% of the adult (>4 years) males were snared. Snared dogs occurred in 67% of packs (n = 6), comprising 14–50% of adult and yearling pack members (median = 20%) and 6–16% of a resident population (median = 6%) already at minimum viable pack size (mean = 5.6). Evidence for seasonal and annual trends differed by patrol type, yet substantial evidence of positive interannual and seasonal trends in snaring existed and there was no evidence of a decreasing trend. Because patrols are intended to reduce poaching and enforcement is adaptive toward increasing snare detection, evaluations of snaring trends from patrol data are potentially confounded; thus we recommend that a portion of the overall patrol effort for anti-poaching should be devoted to non-adaptive surveys under fixed, well-designed protocols to enable unbiased tracking of snaring trends over time and objective evaluation of anti-poaching and community conservation efforts. In addition precautionary management emphasizing increased law enforcement is essential to protect existing wildlife-based economies and resources.

African lions (Panthera leo) are declining continent-wide, with protected area populations subject to a variety of anthropogenic effects. Zambia contains viable lion populations of considerable importance for photographic and hunting tourism, but long-term lion demographic data do not exist to guide recent management directives and population projections under different strategies. We described population size, as well as age and sex structure of lions in 3 Zambian national park populations bordering hunting areas, and found them to be male-depleted relative to other systems. We then estimated rates of adult male loss leading to male depletion in these populations and the effect of different future hunting management options on population characteristics. Predictions from matrix population models constructed within a Bayesian framework confirmed that the observed population structure was likely due to high rates of adult male loss and that instituting age limits on male harvests with quota reductions would reduce male depletion, improve tourism by providing older and more abundant males, and slightly increase population size. Reducing male mortality from wire snare poaching would also result in similar demographic impacts, and in concert with changes in hunting regulations would substantially improve the quality and quantity of adult male lions. However, model results varied depending on whether we assumed historical population stability. Predictions assuming negative historical growth rate indicated that substantially more conservative lion harvest management is warranted. We discuss the relevance of these findings for maintaining viable lion populations in and around protected areas in Zambia. © 2012 The Wildlife Society.