Fenced Reserves Research Articles

Wild lions in small, fenced reserves in South Africa conform to a meta‐population

Abstract Lions (Panthera leo) are declining across their range, mainly due to human‐induced habitat fragmentation and prey depletion. However, the South African lion population continues to grow. Unlike other range states, South Africa actively manages wild lions across a continuum of landscapes and ecological constraints. Many of these lions are in small, fenced reserves where managers seek to mimic ecological processes in small landscapes. However, the effectiveness of this management approach has not been evaluated against meta‐population criteria. Given that meta‐population dynamics allows species living in fragmented habitats to persist, we evaluated how South Africa's lion population complies with meta‐population criteria using national audit data between 2010 and 2019 from 49 fenced, wild lion reserves. The small, fenced reserves holding wild lions fulfil the criteria for meta‐population functionality. However, this functionality was achieved through haphazard and uncoordinated management actions and not through a coordinated approach. Our main recommendation is to consider implementing a more coordinated meta‐population management approach. At the very least, meta‐population management guidelines should be reviewed and updated on a regular basis, regular audits should be conducted and periodic genetic evaluation of the meta‐population (every 10 years) should be instituted. We recommend incentivising lion managers to enhance the conservation of lions in South Africa within a meta‐population framework. We also recommend a focus on improving decision making and policy procedures that facilitates compliance with relevant legislation aimed at achieving high levels of lion conservation‐governance efficiency. South Africa's meta‐population approach to wild lion management in small, fenced reserves is effective at conserving lions and contributing to lion conservation more broadly. In an increasingly fragmented landscape, the need for human management actions to ensure persistence of large carnivores is likely to increase. A managed meta‐population approach of fenced (or unfenced, but geographically isolated) populations is a useful tool for conservationists to consider worldwide.

Baboons (Papio spp.) as a potentially underreported source of food loss and kleptoparasitism of cheetah (Acinonyx jubatus) kills

Kleptoparasitism, the theft of food from another individual, is an important interspecific interaction that can have consequences for animal fitness, predation rates, and species' abundance. Similarly, loss of food to fear effects and interspecific interactions can influence energetic costs and consumption rates. Due to their smaller body size and predominantly solitary nature, cheetahs (Acinonyx jubatus) are particularly prone to negative, direct interactions with competing carnivores, and they frequently lose kills to apex predators. However, trophic interactions with other species may have been underreported in the literature. Here, we document anecdotal interactions between cheetah and baboon (Papio spp.) species, across multiple sites in Africa, where baboon troops chased cheetahs off their kills and, in some cases, fed on the remaining carcasses. Given the widespread distribution, and relatively high densities of baboon species across sub-Saharan Africa, we hypothesise that these interactions are likely to be underrepresented in the literature. Since cheetah already experience high levels of competition with apex predators, particularly in South African fenced reserves where competing carnivores are often stocked at densities approaching, or in some cases exceeding, carrying capacity, additional competition and the loss of prey to baboons could further increase predation rates and have implications for reserve management. Baboons are often defensive around large carnivores. As such, interactions with cheetahs are likely to be motivated primarily as a defensive strategy. We encourage further research into food loss, kleptoparasitic behaviour and other competitive interactions between cheetah and Papio species.

Roadmap to recovery revealed through the reintroduction of an IUCN Red List species

Reintroductions are powerful tools for tackling biodiversity loss, but the resulting populations can be intrinsically small and vulnerable. It is therefore critical to maximise the number of individuals that are available to contribute to recovery efforts. To address this, we investigated how demographic parameters from a reintroduced population can reveal threats to long-term persistence, inform thresholds for management interventions, and create targets for removing an endangered species from the IUCN Red List. We calculated capture-mark-recapture population estimates for eastern quolls (Dasyurus viverrinus) which had been reintroduced to a fenced reserve in the Australian Capital Territory. We then incorporated the resulting demographic parameters into population viability analyses (PVAs) to estimate probabilities of persistence under several scenarios, including supplementations and harvests (removal of individuals for translocation to other locations). After determining sustainable harvest rates, we then ‘back-cast’ the population size and occupancy area required to remove the species from the IUCN Red List within 10 years. Our demographic results indicated high mean apparent survival (90% ± 5), and PVAs revealed the probability of persistence over a 50-year time horizon was 50.5% with no interventions, 0% when the population was harvested of > 6 individuals, and 100% if harvests ≤ 54 juveniles were combined with an annual supplementation of ten maternal females (with ≤ 6 young each). Based on this model, a total harvest area of 413 km2 and an occupancy area of 437 km2 would be needed to recover the species within 10 years (i.e., 90 similar fenced reserves, not accounting for edge effects). Due to the inherent difficulty in securing large areas for species recovery, we see these ambitious targets as a call to create coordinated and collaborative sanctuary networks where species can be managed as a metapopulation across multiple sites. By taking advantage of a rapid life history and harvesting the ‘doomed surplus’, managers can achieve their stretch goals for species recovery in the long term.

Can native predators be used as a stepping stone to reduce prey naivety to novel predators?

AbstractPredator naivety negatively affects reintroduction success, and this threat is exacerbated when prey encounters predators with which they have had no evolutionary experience. While methods have been developed to inculcate fear into such predator-naïve individuals, none have been uniformly successful. Exposing ontogenetically- and evolutionary-naïve individuals first to native predators may be an effective stepping stone to improved responses to evolutionarily novel predators. We focused on greater bilbies (Macrotis lagotis) and capitalized on a multi-year mammalian recovery experiment whereby western quolls (Dasyurus geoffroii) were reintroduced into parts of a large fenced reserve that contained a population of naïve bilbies. We quantified a suite of anti-predator behaviors and measures of general wariness across quoll-exposed and quoll-naive bilby populations. We then translocated both quoll-exposed and quoll-naïve individuals into a large enclosure that contained feral cats (Felis catus) and monitored several behaviors. We found that bilbies can respond appropriately to quolls but found only limited support that experience with quolls better-prepared bilbies to respond to cats. Both populations of bilbies rapidly modified their behavior in a similar manner after their reintroduction to a novel environment. These results may have emerged due to insufficient prior exposure to quolls, inappropriate behavioral tests, or insufficient predation risk during cat exposure. Alternatively, quolls and cats are only distantly related and may not share sufficient similarities in their predatory cues or behavior to support such a learning transfer. Testing this stepping stone hypothesis with more closely related predator species and under higher predation risk would be informative.

Fence management and time since pack formation influence African wild dog escapes from protected areas in South Africa

In human-dominated and highly fragmented landscapes, keeping wildlife within reserve boundaries is vital for conservation success. In South Africa, fences are a widely employed conservation management tool for protected areas and are successful in mitigating human-wildlife conflict. However, fences are permeable, and predators are able to cross through reserve fences. African wild dogs (Lycaon pictus) often leave fenced boundaries, resulting in high capture and translocation costs. Moreover, when wild dog packs (up to 30 individuals) leave fenced reserves they enter human-dominated landscapes where they face strong persecution and livestock predation incurs high costs. The factors driving packs to leave managed reserves are poorly understood, thus, to effectively manage wild dogs in fenced systems, it is important to understand why they leave reserve boundaries. There are several hypotheses as to why wild dogs cross through reserve fences, including inter- and intra-specific competition, social behaviour, management, prey density and environmental variability. Using a long-term dataset comprising 32 resident packs across five reserves, we investigated the relative strength of these hypotheses on the probability of wild dogs exiting a fenced reserve. During the 14-year study period, we recorded 154 exit events. We found that the interaction of fence integrity and time since pack formation were the primary factors affecting the probability of a pack leaving a reserve. When fence integrity was poor, escape probability decreased with pack age likely due to the exploratory behaviour of new packs. When fence integrity was average, escape probability increased with pack age likely due to the fitness benefits of holding larger and more exclusive territories as packs age. When fence integrity was good, the probability of a pack escaping was very low (only 1% occurrence). The implications of this research suggest that the primary management consideration for reducing wild dog escapes from fenced reserves should be maintaining adequate reserve-wide fence integrity, rather than focusing on social structure or drivers of inter- and intra-specific competition.

Simulated genetic efficacy of metapopulation management and conservation value of captive reintroductions in a rapidly declining felid

AbstractIn South Africa, cheetahs (Acinonyx jubatus) occur as a relictual, unmanaged population of ‘free‐roamers’, a managed metapopulation across fenced reserves, and in various captive facilities. To ensure that the Cheetah Metapopulation Project (CMP) is not at risk of losing overall genetic variation to drift or inbreeding, we propose various interventions, including exchanges between free‐roamers and the metapopulation or supplementation with unrelated individuals from captivity. Simulated trajectories of genetic diversity under such intervention strategies over time could directly inform conservation action and policy towards securing the long‐term genetic integrity of the CMP. Single Nucleotide Polymorphisms (SNPs) were genotyped for 172 adult cheetahs across the free‐roamer population, the metapopulation, and three major captive facilities. Management intervention trajectory models were tested including, (1) no intervention, (2) genetic exchange between free‐roamers and the metapopulation, (3) translocation from a single captive facility and (4) translocation from several captive facilities into the metapopulation. Discriminant Analysis of Principal Components (DAPC) showed that two captive populations are highly differentiated from the metapopulation and each other, whilst the third captive and free‐roamer populations are genetically more similar to the metapopulation. Simulated genetic variation over 25 generations indicated that models 1 and 2 show significant losses of heterozygosity due to genetic drift and present a proportional increase in the frequencies of 1st‐ and 2nd‐degree relatives, whilst this variation and pairwise relatedness remain relatively constant under models 3 and 4. We emphasise the potential importance of captive facilities as reservoirs of genetic diversity in metapopulation management and threatened species recovery.

Home Range and Movement Patterns of Reintroduced White Lions (Panthera leo melanochaita) in the Kruger to Canyons Biosphere Reserve, South Africa.

Simple SummaryWhite lions are a natural colour variant of the African lion found within certain lion prides in the Greater Kruger Park Region of South Africa. Human factors led to their absence until white lions were reintroduced in 2006. This study provides the first assessment of home range and movement behaviour of white lions as an index of reintroduction success. Home range is the area where an animal spends its time and encompasses all the resources the animal requires to survive and reproduce. The home range size and average distance walked in a day were compared seasonally (wet compared to dry season) and between sexes (male compared to female) for a pride of white lions and a pride consisting of white and tawny (nonwhite) lions. Both prides had similar sized home ranges, walked a comparable average distance, and preferred similar types of vegetation among which to spend their time (dense woodland compared to open grassland). The white lions from both prides showed natural behaviour, similar to wild lions in terms of how they established and made use of their home ranges, suggesting that white lions can be successfully reintroduced into the wild.White lions are a colour variant of the African lion Panthera leo melanochaita and disappeared from the wild due to anthropogenic factors until their reintroduction to the Greater Kruger Park Region of South Africa in 2006. Natural home range behaviour is an index of reintroduction success. Therefore, the home range and movement of a pride of reintroduced white lions and a constructed pride consisting of reintroduced white lions and translocated wild tawny lionesses in small, fenced reserves was assessed. GPS data from collared adults were collected for the white lion pride between 2010–2011 and 2018–2020 for the constructed pride. Home ranges were estimated using kernel density estimation and minimum convex polygon, with minimum daily distance tested for differences between sex, season, and pride. Home ranges were small and average daily movements restricted for both prides (white lion pride: 5.41 km2 and 10.44 ± 4.82 km; constructed pride: 5.50 km2, 11.37 ± 4.72 km) due to the small reserve size of 7 km2. There was no difference between prides for annual and seasonal home range size, male and female home ranges, minimum daily distance travelled, or habitat selection. White lions from both prides established territories and displayed natural home ranging behaviour, suggesting that their reintroduction was successful, in the absence of anthropogenic threats.

Assessing the Social Cohesion of a Translocated Pride of White Lions Integrated with Wild Tawny Lions in South Africa, Using Social Network Analysis.

Simple SummaryLions in South Africa are protected in national parks and smaller fenced private wildlife reserves. Population sizes and genetics within fenced reserves are managed through moving lions between reserves. One component of successful lion movements is their ability to form prides post release, which is influenced by the strength of social bonds and interactions between individual lions. White lions are a natural colour variant of the African lion, occurring within certain tawny lion prides in the Greater Kruger National Park, South Africa. Human impact, including trophy hunting, led to the removal of white lions in the wild until their reintroduction in 2006. The social behaviour of a pride consisting of captive-origin white and wild tawny lions was compared to captive-origin and wild tawny lion prides, with similarities and differences in the social behaviour of prides found. The study concluded that the pride of white and tawny lions was more strongly bonded than either the captive-origin or wild tawny prides. This suggests that a constructed pride of captive-origin white and wild tawny lions can successfully form a socially functional lion pride and indicates that white lions are capable of surviving in the wild in the absence of negative human impact. In South Africa, lions are protected in national parks and smaller fenced reserves. Translocating lions between fenced reserves, whilst necessary to maintain genetic diversity, is disruptive and can impact survivorship and pride cohesion. Critical to translocation success is pride cohesion. White lions are a natural colour variant occurring in the Greater Kruger Park Region, where anthropogenic threats eliminated this population until reintroduction in 2006. Through social network analysis (SNA), the sociality of a released pride of captive-origin white and wild tawny lions was compared to two captive-origin and wild prides of tawny lions. Social interactions and pride dynamics were recorded for each pride. For all prides, cubs and subadults were central to the play network, while adults received the most social interactions. White and wild tawny adult males initiated more social interactions than captive-origin tawny males, whilst a keystone adult female was identified in each pride. For the constructed pride, social interactions were more evenly distributed, suggesting a high level of connectedness and cohesion. This is the first study to demonstrate that captive-origin white and wild tawny lions can form a socially functional pride, suggesting that white lions would survive in the wild in the absence of anthropogenic threats.

The impacts of management interventions on the sociality of African lions (Panthera leo): Implications for lion conservation

Abstract African lion (Panthera leo) populations normally consist of several neighbouring prides and multiple adult males or groups of males that interact competitively. In large, open systems, cub defence from infanticidal males and territory defence drive group living in lions. However, in smaller (<1000 km2), fenced wildlife reserves, opportunities for natural immigration and emigration are limited which means that the evolutionary drivers of lion sociality may collapse. Here, we use lion behavioural data collected from 16 wildlife reserves across South Africa to test how management‐induced ecological conditions alter lion social dynamics. The number of lionesses observed together was best predicted by pride size, prey biomass and biome. Lionesses were less likely to group together as pride size increased, but more likely to group together as prey biomass and habitat productivity increased. In addition, adult males were observed more frequently with prides that had young (<12 months) cubs in reserves that had unfamiliar adult males present compared to reserves without any unfamiliar adult males. Our results demonstrate how intraspecific competition between lions drives their sociality, and this may break down in small, fenced wildlife reserves where lions are actively managed. Although small, fenced reserves in South Africa have made a significant contribution to increasing lion numbers on the continent, our work highlights several important ecological implications of active lion management. For wildlife managers, mimicking the outcomes of different levels of intraspecific competition is likely a critical management tool for the persistence of lions in small reserves.

The effect of insects on elephant‐induced tree damage within a small, fenced reserve in South Africa

AbstractAfrican savanna elephants (Loxodonta africana) have been recognised as ecosystem engineers, where their feeding habits have been shown to alter landscapes. Within small, fenced reserves, studies exploring elephant damage on trees and their recovery have overlooked secondary damages that could be contributing to tree mortality. The aim of this study is to assess the significance of both elephant damage and secondary damage, and the subsequent tree recovery. We identified secondary damage as insects and considered wood borers and termites in this study. This was conducted in in the small fenced Karongwe Private Game Reserve, South Africa. We analysed the level of damage, recovery and insect presence using vegetation transects, where all trees ≥2 m in height were surveyed (n = 1278 trees). Forty tree species were recorded, with 5 species accounting for 77% of the data set and used for further analysis. Termites were found to be more likely to colonise damaged trees without signs of recovery. However, wood borers were more likely to colonise damaged trees showing signs of recovery. Termites and wood borer presence on damaged trees was not dependent on tree height. We suggest carefully considering management approaches for elephant‐induced termite and wood borer damage on trees.

Camera traps reveal a large population of brown hyaena on a fenced reserve in southern Zimbabwe

AbstractInvestigations into the demographics of cryptic carnivores such as the near‐threatened brown hyaena Parahyaena brunnea have been improved by recent developments in camera trap technology and survey methods. Here, we assess the population density and abundance of this species on the Bubye Valley Conservancy (BVC) in south‐west Zimbabwe, a largely unsurveyed portion of the brown hyaena's range. We estimated brown hyaena density from a camera trap survey across two sections of the BVC (namely Main Conservancy and Ripple Creek) using a spatially explicit capture‐recapture method from individually identifiable images. This resulted in population density estimates of 14.72 ± 0.99 per 100 km2 for the Main Conservancy and 6.39 ± 1.74 for the Ripple Creek. While similar results have been found in recent studies of small, fenced reserves in Southern Africa, to our knowledge, these high‐density findings are the first for a large (>1000 km2) fenced reserve. We estimated the brown hyaena population on the BVC to be in excess of 400 individuals. This considerable population size is likely due to the well‐protected nature of the reserve and the scavenging opportunities provided by the sympatric large carnivores on the BVC, suggesting that this is a key locale for the species' conservation.

Impacts of African savannah elephants (Loxodonta africana) on tall trees and their recovery within a small, fenced reserve in South Africa

AbstractAfrican savannah elephants (Loxodonta africana) can have detrimental impacts on trees; studies exploring elephant impact within small, fenced reserves, have lacked focus in determining elephant high‐use areas, the direct effect of fence line and tree recovery. The aim of this study is to assess whether elephants cause significant impact on trees in the small‐fenced Karongwe Private Game Reserve (KPGR) and to determine the levels of tree recovery. Trees ≥5 m in height were surveyed (n = 634 trees). Elephant location data were used to identify high‐ and low‐use areas. Five species accounted for 80% of the records; these were used for further analysis. Trees in high‐use areas were significantly less likely to show signs of debarking and push over. Tall trees were significantly more likely to be impacted by elephants, being associated with heightened risks of debarking and branches being broken but lower risks of being pushed over. Trees close to the fence line were not more impacted than trees near the centre of the reserve. The level of use, distance to the fence and tree height were not significant predictors of tree recovery indicators. Future mitigation efforts should focus on trees with high levels of impact and low levels of recovery.

Rapid population expansion of Boodie (Burrowing Bettong, Bettongia lesueur) creates potential for resource competition with Mala (Rufous Hare‐wallaby, Lagorchestes hirsutus)

SummaryTranslocations to closed systems such as fenced reserves are commonly used for conservation of threatened fauna species worldwide; however, resources are limited in these areas, and natural processes that regulate populations in response to resource availability are unable to occur. This can result in overabundance followed by overuse of resources, potentially resulting in extreme declines or local extinctions. Resource exhaustion can negatively impact other fauna in the closed environment that exploit similar resources, through inter‐specific competition. This paper discusses the reintroduction of Boodie (Bettongia lesueur) and Mala (Lagorchestes hirsutus) to a fenced reserve on the Matuwa Indigenous Protected Area, Western Australia, and raises the concern of potential competition between the two threatened species.

The Influence of Population Demographics on Lion (Panthera leo) Growth Rates in Small, Fenced Wildlife Reserves

Rapid population growth of reintroduced lions (Panthera leo) poses several ecological and management challenges in small (<1000 km2), fenced wildlife reserves. Changes in the natural social-ecological conditions of reintroduced lions can lead to a breakdown of natural predator–prey relationships and this is undesirable from both a biodiversity conservation and wildlife management perspective. Here, we present lion population vital rates across 16 small, fenced reserves in South Africa to test whether varying social ecological conditions, associated with lion population structures, can drive changes in vital rates. Study reserves were categorized (A–D) according to the number of resident prides and male coalitions. Lion population structure within a reserve affected lion vital rates differentially, and lion population growth was highest in reserves that contained a single resident pride. The presence of more than one pride in a reserve resulted in a younger age at first birth and marginally longer birth intervals. The presence of extra-pride adult males reduced cub survival, lioness age at first birth and birth intervals. These results can inform lion management decisions and, in particular, how lion population structure affects management outcomes. Our results also inform appropriate management protocols for lions depending on the specific social and ecological context of an individual reserve.

Effects of mammal exclusion on invertebrate communities in New Zealand

AbstractIn the absence of mammals, the fauna of islands is characterised by high endemism levels and a tendency towards gigantism, flightlessness and longevity. These characteristics have resulted in a high vulnerability to introduced animals, either directly via predation or indirectly through an alteration of food web interactions. Because invertebrates are important components of food webs and essential for many ecosystem processes, we investigated how different mammal and bird communities, present inside and outside a fenced reserve, influenced ground‐dwelling invertebrates on the mainland of New Zealand. Some significant differences in invertebrate community composition were apparent inside versus outside the fenced reserve, predominantly Ctenognathus adamsi (Carabidae) being twenty times more abundant inside the reserve, and rove beetles (Staphylinidae) being eight times more abundant outside the reserve. The introduced blackbird (Turdus merula) was observed more regularly than other predators of invertebrates outside the reserve, while native robins (Petroica longipes) were more highly detected inside the reserve. Despite differences in the vertebrate insectivore community outside the reserve (multiple mammals and introduced birds) compared to inside (mainly native birds), the resulting similarity in net predation pressure may explain the apparent similarity in abundance for most of the other 24 invertebrate taxa examined. Removal of most mammals from within fenced reserves in New Zealand may enable introduced and native birds to flourish, with flow‐on effects on the invertebrate community. We conclude that further study of trophic interactions and additional intervention, may need to be considered if invertebrate conservation is a desired outcome from fenced reserves.

Exposure to a novel predator induces visual predator recognition by naïve prey

The “life-dinner principle” posits that there is greater selection pressure on the species that have more to lose in an interaction. Thus, based on the asymmetry within predator-prey interactions, there is an advantage for prey to learn quickly, especially in response to novel, introduced predators. Here, we test the “learned recognition” hypothesis that posits that naive prey species’ ability to recognise and respond to introduced predators can be induced through experience. We quantified the behavioural response of initially predator-naive burrowing bettongs (Bettongia lesueur) that had been living in the presence (for 8–15 months) and absence of an introduced predator (feral cats—Felis catus) to models of cats, a herbivore (rabbit (Oryctolagus cuniculus)), novel object (plastic bucket) and no object (control). We expected that if bettongs recognised cats as a threat, they would be more wary in the presence of cat models than either rabbit models, buckets or the control. Bettongs living without predators did not modify their behaviour in response to the cat model, but spent more time cautiously approaching the rabbit model compared with the control. However, bettongs living with cats spent more time cautiously approaching the cat model compared with the rabbit, bucket and control. Our results are consistent with the learned recognition hypothesis which suggests that a predator-naive prey species ability to recognise novel predators is inducible through experience. Our finding suggests that antipredator responses of reintroduced species could be improved prior to release by exposing them to predators under carefully controlled conditions. Predator-prey interactions have played a strong selective factor in the evolution of predator avoidance behaviour by prey. In order for prey to appropriately and successfully respond and avoid predation, it is essential that prey species recognise a predatory threat in the first place. The isolation of prey species on predator free islands, geographically isolated continents (such as Australia) and predator-free fenced reserves, means that prey are increasingly isolated from predator-driven natural selection processes. We studied the behavioural response of a population of initially predator-naive burrowing bettongs that had been living in the presence (for 8–15 months) and absence of feral cats, (an introduced predator). Our results show that predator-naive prey species’ ability to recognise novel predators is inducible through experience.

Factors influencing the residency of bettongs using one‐way gates to exit a fenced reserve

AbstractUnderstanding the conditions under which small native Australian mammals can persist in the presence of introduced predators remains a key challenge to conservation ecologists. Bettong‐specific one‐way gates were used at a predator‐free reserve in South Australia to allow the burrowing bettong (Bettongia lesueur) – a small potoroid, listed as ‘vulnerable’ nationally – to disperse out of the reserve. We conducted a field experiment to explore the conditions affecting residence time of bettongs that left the reserve. We monitored bettong and mammalian predator activity outside the fence using track surveys across 18 sites over two seasons. We examined the effect of supplementary feeding as a strategy for increasing residence time, as well as the influence of predator presence and habitat quality, using linear mixed models. Bettong activity was positively associated with supplementary feeding, midstorey vegetation cover and shelter availability. After gates were closed, bettong activity near gates declined to almost zero the following weeks, likely either due to death from predation or due to movement away from the sites. To a small extent, mammalian predators were more likely to be present at sites with high bettong activity. Further research on conditions to support persistence of burrowing bettongs and other small mammals, including understanding minimum necessary predator control effort, is required before successful establishment of populations outside of fences can occur.

Opportunistic feeding by lions: non-preferred prey comprise an important part of lion diets in a habitat where preferred prey are abundant

Optimal foraging theory predicts less diverse predator diets with a greater availability of preferred prey. This narrow diet niche should then be dominated by preferred prey, with implications for predator–prey dynamics and prey population ecology. We investigated lion (Panthera leo) diets in Hluhluwe–iMfolozi Park (HiP), South Africa, to assess whether lions in a site with a high density of preferred prey (prey species weighing 92–632 kg as estimated from a published meta-analysis) have a narrow diet, consisting primarily of preferred prey. HiP is a useful study site to investigate this prediction because it is a productive landscape (with a high density of prey) where lion-preferred prey constitutes up to 33% of the prey available to lions. Furthermore, to investigate whether lions in HiP exhibit sex-specific diets as documented in other southern African populations, we estimated male and female lion diets separately. We were specifically interested in testing whether traditional approaches of estimating lion diets at the population level mask sex-specific predation patterns, with possible implications for management of lions in small to medium-sized fenced reserves. Lions in HiP preferred larger prey species (63–684 kg) and had diets with a larger proportion of preferred prey than reported in an African-wide meta-analysis. However, despite the high density of preferred prey species, 36% of lion diets still consisted of typically non-preferred species such as nyala (Tragelaphus angasii). This finding suggests that lions in HiP maintain a degree of opportunism even when preferred prey are abundant. Therefore, abundant, non-preferred prey are likely to be an important resource for lion populations. Sex-specific differences in lion diets were evident in HiP, suggesting that estimation of lion resource use and carrying capacity should consider opportunistic hunting and sex-specific differences in lion diets.

BASELINE HEALTH AND DISEASE ASSESSMENT OF FOUNDER EASTERN QUOLLS (DASYURUS VIVERRINUS) DURING A CONSERVATION TRANSLOCATION TO MAINLAND AUSTRALIA.

We evaluated the health of 31 (eight males, 23 females) founder eastern quolls (Dasyurus viverrinus), translocated to a fenced reserve in the Australian Capital Territory between February 2016 and July 2017. Quolls were wild caught in Tasmania (16 animals) or captive bred at Mount Rothwell Biodiversity Interpretation Centre, Victoria (15 animals). Quolls were assessed for the presence of selected potential pathogens (Toxoplasma gondii, herpesviruses, Salmonella serovars, hemoprotozoa, and ectoparasites). We assessed the relationships among sex, provenance (captive or free ranging), T. gondii or herpesvirus infection, weight, and hematologic and biochemical variables. Six of 21 quolls (29%) tested were seropositive for antibodies to T. gondii. Seropositive quolls weighed significantly more and had significantly lower potassium levels, anion gaps, and urea and triglyceride levels than seronegative quolls had. Eighteen of 31 (58%) combined conjunctival-pharyngeal-cloacal swabs collected from quolls were PCR positive for a newly identified gammaherpesvirus, tentatively named dasyurid gammaherpesvirus 3. There were no significant differences among hematologic and biochemical variables or body weights from PCR-positive and PCR-negative quolls. Eighteen of 18 (100%) of rectal-swab samples were culture negative for Salmonella serovars. Three species of tick (Ixodes tasmani, Ixodes fecialis, and Ixodes holocyclus), two species of mite (Andreacus radfordi, one unidentified), and four species of flea (Pygiopsylla hoplia, Acanthopsylla rothschildi rothschildi, Uropsylla tasmanica, and Stephanocircus dasyuri), were detected on wild-caught quolls, whereas a fifth species of flea, Echidnophaga myremecobii, was detected only on captive-bred quolls. Five of 15 blood samples (33%) were positive for hemoprotozoan DNA via PCR, a novel Hepatozoon species, a novel Theileria species, Theileria paparinii, and Trypanosoma copemani were detected. Despite the presence of several potential pathogens known to be associated with disease in other marsupials, the quolls were considered to be in good general health, suitable for translocation, and a viable population was subsequently established.

Canine Distemper Virus Management in Lions (Panthera leo) on Welgevonden Game Reserve

Large charismatic predators have been re-introduced to several fenced reserves (<1000 km2); consequently, their populations can be at risk to declining genetic diversity and catastrophic events such as disease. Welgevonden Game Reserve (WGR) experienced an outbreak of canine distemper virus (CDV) in its lion (Panthera leo) population between October 2015 and February 2016. The decline was attributed to both direct CDV mortalities and indirect management interventions with a population decrease of 93%. In addition, the first documented cases of CDV were recorded in a brown hyaena (Hyaena brunnea) population. This article shares the management of a disease outbreak in WGR's lion population. It discusses the population history, the making of clinical observations leading to diagnoses and recommends strategies that can be implemented to prevent extirpation. The sourcing of new lions from established meta-populations, and the use of vaccinations to proactively prevent future outbreaks in managed wild lions is discussed. In less than two years the population has recovered. This paper provides a case report for wildlife practitioners of small populations of managed wild lions.