Lourens H. Swanepoel

Survival rates and causes of mortality of leopards Panthera pardus in southern Africa

The International Foundation of Science (D/4984-1), Wild Foundation (2008-011), Wilson Foundation and the University of Pretoria. LHS was further supported by the National Research Foundation (74819), FD by the National Research Foundation and a research fellowship from the University of Pretoria, and MJS by the Department of Science and Technology Centre of Excellence for Invasion Biology and the National Research Foundation.

The importance of refugia, ecological traps and scale for large carnivore management

Management zones feature prominently in conservation planning, particularly at large spatial scales, but prioritization of areas of concern is required to focus efforts and limited resources. Human-mediated mortality constitutes a major threat to species persistence, particularly for widespread carnivores that undergo harvest and population control, such as the leopard (Panthera pardus). In this study, we evaluated the extent and spatial distribution of legal anthropogenic offtake of leopards to identify de facto refugia and ecological traps across Limpopo Province, South Africa. We defined refugia as management units with offtake levels below an established sustainable harvest rate, and ecological traps as management units with offtake exceeding the sustainable harvest rate. We assessed offtake at three geographical scales using trophy hunting permit records alone, and then in combination with problem leopard permit records to investigate the compounding effect of additional forms of offtake and the potential for management scale mismatching. Across Limpopo Province, high leopard offtake created fewer areas of refuge than ecological traps. Refugia were smaller in size and within close proximity of ecological traps. Human-mediated leopard mortality occurred mostly in prime leopard habitat. Finer-scaled management units resulted in fewer ecological traps and more refugia, and enables authorities to focus conservation attention in areas of concern. Human-mediated leopard mortality exceeded the annual offtake rate considered sustainable. Our study highlights the importance of assessing both the scale and distribution of the harvest, whilst also considering alternative forms of offtake, when devising harvest management strategies. Management scale mismatching and high human-mediated leopard mortality is of particular concern in Limpopo Province, as such, we propose an adaptive, science-based regulatory framework aimed at improving leopard harvest strategies.

Factors Affecting Location Failure of GPS Collars Fitted to African Leopards (Panthera pardus)

Recent technological advances in Global Positioning system (GPS) technology have generated an Increase in the use of GPS collars fitted to wild animals to track their movements. GPS units are advantageous compared to other methods of remote tracking of animals in that the have the ability to gather large quantities of spatial data that may be accessed remotely. However, animal behaviour, topography, vegetation, and seasonality could all influence GPS acquisition success and therefore bias results from GPS technology. Here we analyse temporal and seasonal patterns associated with GPS acquisition failures in five GPS collars fitted to leopards (Panthera pardus) in the Waterberg region of South Africa. Of 6565 attempted GPS acquisitions, 19% (1236) failed with the location failure rate of Individual collars ranging from 15–29%. Single failed attempts accounted for the majority of location failures, suggesting that failure was caused by temporary blockage to satellites. Failure rates were significantly higher during the day and there were Indications that they were higher during the wet season than in the dry season. Failures were also clustered in space for some Individual animals. Our results suggest that temporal patterns of animal behaviour and habitat choice Influence the probability of GPS location failures in this species. We therefore suggest that potential biases should be accounted for when using GPS data to analyse movement and habitat selection in this and similar carnivore species.

Patterns of scat deposition by brown hyaenas Hyaena brunnea in a mountain savannah region of South Africa

Abstract The brown hyaena Hyaena brunnea is a near threatened large carnivore inhabiting sub-Saharan Africa. Like many other species of terrestrial carnivores, brown hyaenas often and repeatedly deposit scats at specific latrine sites as a means of olfactory communication. However, previous studies on brown hyaena latrine use have been constrained to the arid Kalahari region in southern Africa, an area of low resource abundance. To improve our understanding of geographic variation in the biology of this species, we monitored patterns of brown hyaena scat deposition in the Waterberg of northern South Africa, an area of higher net productivity than previous areas for published brown hyaena studies. Defecation rates at latrine sites were low in our study area (median: < 1 defecation in 30 days), but brown hyaenas visited sites significantly more often than they defecated at them (median: 2.6 visits/30 days). The temporal patterns of activity at defecation sites were significantly related to the overall temporal activity patterns of brown hyaenas on the roads within the reserve, and generally confirmed a nocturnal activity pattern in the species. Our result on brown hyaena scat deposition in the Waterberg region indicates a geographic variation in latrine use, and we suggest that such a variation could be linked to resource-driven variation in social and spatial organisation.

The Relative Importance of Trophy Harvest and Retaliatory Killing of Large Carnivores: South African Leopards as a Case Study

There are considerable challenges in the conservation of large carnivores, caused by large area requirements, low reproduction rates and low population densities coupled with their tendency to cause conflict with humans. Trophy hunting is one strategy to increase support for large carnivore conservation. Leopards, Panthera pardus, rank among the most sought-after trophies in South Africa. However, trophy hunting has been suggested as partly responsible for leopard population declines, and leopards are also killed in retaliatory actions. In this study we used a stochastic population model to evaluate the relative influences of retaliatory killing and trophy harvest on leopard population persistence, and to assess the sustainability of the current leopard trophy harvest in South Africa. There was a stronger effect of variation in retaliatory killing than of harvest on population persistence. Although we found low extinction risks for South African leopards within 25 years, high risks of population declines across a wide range of simulation scenarios call for concern regarding the viability of the South African leopard population. We suggest that conflict mitigation may be more effective in promoting leopard persistence than restricting trophy harvest, and that accurate estimates of retaliatory killing are necessary for assessments of harvest sustainability.

Effect of prey mass and selection on predator carrying capacity estimates

The ability to determine the prey-specific biomass intake of large predators is fundamental to their conservation. In the absence of actual prey data, researchers generally use a “unit mass” method (estimated as 3/4 adult female mass) to calculate the biomass intake of predators. However, differences in prey preference and range across geographic regions are likely to have an influence on biomass calculations. Here we investigate the influence of estimated prey mass on leopard biomass calculations, and subsequent carrying capacity estimates, in an understudied mountain population. Potential leopard feeding sites were identified using global positioning system (GPS) location clusters obtained from GPS collars. We investigated 200 potential leopard feeding sites, of which 96 were actual feeding sites. Jaw bones, horns, hooves, and other indicative bones were used to determine gender and age of prey items, which were subsequently used to calculate mass of each prey item based on previously published values. There were significant differences in the biomass values calculated using the traditional unit mass method and the calculated prey masses obtained from leopard feeding sites. However, there were no considerable differences in the carrying capacity estimates using the preferred prey species model and leopard density estimates calculated using a non-biased spatial approach, which suggests that estimating carnivore carrying capacity based on 3/4 adult female masses is a reliable method also for the mountain population in this study.

Density of leopards Panthera pardus on protected and non-protected land in the Waterberg Biosphere, South Africa

Data on the population size and trends of large carnivores remains the cornerstone of effective management and conservation programs. However, such data are rarely available for the majority of large carnivore species. Furthermore, large carnivore research is often directed towards formally protected areas. There is therefore a need to improve our knowledge regarding the population ecology of large carnivores in non-protected areas. In this study we use camera trapping in conjunction with spatially explicit mark—recapture models to estimate leopard Panthera pardus density across different land use types in the Waterberg Biosphere, South Africa. Estimated densities (mean ± SE) ranged from 6.59 (± 5.2/100 km2) on a matrix of commercial game and livestock farms to 5.35 (± 2.93/100 km2) and 4.56 (± 1.35/100 km2) on two protected areas (Lapalala and Welgevonden respectively). Although density estimates had large confidence intervals we suggest that these results indicate similar densities across the three sites. These results support other studies suggesting that non-protected areas can harbour as dense leopard populations as protected areas, and can therefore not be neglected in the management of leopards.

Cats, connectivity and conservation: incorporating data sets and integrating scales for wildlife management

Understanding resource selection and quantifying habitat connectivity are fundamental to conservation planning for both land-use and species management plans. However, datasets available to management authorities for resource selection and connectivity analyses are often highly limited and fragmentary. As a result, measuring connectivity is challenging, and often poorly integrated within conservation planning and wildlife management. To exacerbate the challenge, scale-dependent resource use makes inference across scales problematic, resource use is often modelled in areas where the species is not present, and connectivity is typically measured using a source-to-sink approach, erroneously assuming animals possess predefined destinations. Here, we used a large carnivore, the leopard Panthera pardus, to characterise resource use and landscape connectivity across a vast, biodiverse region of southern Africa. Using a range of datasets to counter data deficiencies inherent in carnivore management, we overcame methodological limitations by employing occupancy modelling and resource selection functions across three orders of selection, and estimated landscape-scale habitat connectivity – independent of a priori source and sink locations – using circuit theory. We evaluated whether occupancy modelling on its own was capable of accurately informing habitat connectivity, and identified conservation priorities necessary for applied management. We detected markedly different scale-dependent relationships across all selection orders. Our multi-data, multi-scale approach accurately predicted resource use across multiple scales and demonstrates how management authorities can more suitably utilise fragmentary datasets. We further developed an unbiased landscape-scale depiction of habitat connectivity, and identified key linkages in need of targeted management. We did not find support for the use of occupancy modelling as a proxy for landscape-scale habitat connectivity and further caution its use within a management context. Synthesis and applications. Maintaining habitat connectivity remains a fundamental component of wildlife management and conservation, yet data to inform these biological and ecological processes are often scarce. We present a robust approach that incorporates multi-scale fragmentary datasets (e.g. mortality data, permit data, sightings data), routinely collected by management authorities, to inform wildlife management and land-use planning. We recommend that management authorities employ a multi-data, multi-scale connectivity approach—as we present here—to identify management units at risk of low connectivity.

Foraging and Habitat Specialization by Female Leopards (Panthera pardus) in the Waterberg Mountains of South Africa

Carnivores that persist outside of protected areas are often deemed to have highly adaptable and generalist foraging strategies. Using data from three GPS-collared female leopards (Panthera pardus) and over an eight-month period, we attempted to establish whether leopards in a mountainous landscape display preferential behaviour (i.e. specialist) or not (i.e. generalist). We investigated whether female leopards used habitats in accordance with availability for both hunting and regular activities, and whether female leopards demonstrated preference for a particular prey species. Finally, we assessed tree caching behaviour and discuss leopard spatial dynamics in the context of superior competitors, such as lions (Panthera leo). Female leopards demonstrated selection for certain prey species. Mixed closed woodland (greatest vegetation density; lowest prey density) and tall open woodland (greatest vegetation biomass; high prey density) were preferred over other habitats. Female leopards on Welgevonden cached significantly larger prey species in trees. Our results suggest that female leopards in this landscape are selecting habitats - enabling the exploitation of certain ecological features - that balance energy expenditure against the likelihood of capturing prey in an attempt to maximize efficiency, whilst reducing inter-specific competition. We suggest that female leopards are limited in their foraging ability as a result of interference competition by superior species like lions, which in turn, affects their choice of prey. These findings highlight the potential importance of numerous ecological, spatio-temporal, and anthropogenic factors that influence leopard behaviour, and therefore have significant implications for leopard persistence and conservation.

Unusually high predation on chacma baboons (Papio ursinus) by female leopards (Panthera pardus) in the Waterberg Mountains, South Africa.

Leopards do not preferentially favour baboons as prey, but they are considered the primary predators of baboons across Africa. Even in areas where baboons are abundant, their contribution to leopard diet seldom exceeds 5% of biomass. It is suggested that the extreme aggressiveness of baboons, group vigilance and their high mobility when escaping may limit leopard predation. Male baboons are particularly aggressive, and retaliation often leads to the death of the leopard. However, evidence suggests that leopards may learn to catch and kill certain dangerous prey. This study reports predation on chacma baboons by 3 female leopards on a private game reserve in the Waterberg Mountains of South Africa. Potential leopard feeding sites were identified using global positioning system (GPS) location clusters obtained from GPS collars. Over a 5-month period, we investigated 200 potential leopard feeding sites and located 96 leopard feeding/kill sites. Baboons constituted 18.7% of the leopards’ biomass intake. The majority of baboons preyed upon were adults and 70% of the kills were diurnal. In terms of the measured variables, there were no significant differences in the way the leopards preyed upon baboons, compared to the rest of the prey species.