Humanity is exerting unprecendented pressure on natural ecosystems and the species living in them. This pressure is particularly evident among the larger members of the order Carnivora. Their large body size (typically in the 25-600 kg range), life history traits, and reliance on large prey species places them at increased risk of extinction. The International Union for the Conservation of Nature (IUCN) Cat Specialist Group, and the Convention of Migratory Species (CMS) both recognize the deficiencies in robust data available on large carnivores across large tracts of Africa. Furthermore, the population estimates we do have are often drawn from less-reliable methods.
The overarching aim of this PhD thesis was to: 1) use a recently-developed population estimation technique (Elliot and Gopalaswamy 2017) to estimate the densities, population size, and population parameters of large carnivores in the Queen Elizabeth Conservation Area (QECA), Uganda, and use these data to inform their conservation status, 2) improve understanding of the conflict between large carnivores and human communities in Lake Mburo, Uganda, and Mumbai, India, and 3) explore alternative methods to fund conservation measures, including compensation and a wildlife imagery royalty.
In Chapter 1 as part of introducing my thesis, I examined the literature on historic and present methods being used to census African lions Panthera leo and together with a team of international collaborators I made a case for the adoption of spatially explicit capture recapture (SECR) methods for African lions. In Chapter 2 I built upon this and showed the utility of using population state variables (namely movement, sex-ratios, and density) in assessing the conservation status of African lions in a poorly known area of East Africa. I used a population of African lions in south-western Uganda’s Queen Elizabeth Conservation Area (QECA), as a model. I conducted a 93-day African lion census in 2017-2018 and compared the results to those from an intensive radio-collaring study from a decade ago. I hypothesized that if the population of African lions in the QECA was stable or increasing, lion movement distances and home ranges would be similar between the two study periods but if movement distances were larger and sex-ratios were male-biased, the lion population was likely declining. I found male lions expanded their ranges by > 400%, and females >100%, overall lion densities were low (2.70 lions/100 km2, posterior SD=0.47), and the sex ratio of lions in the system was skewed towards males (1 female lion: 2.33 males), suggesting a decline. I concluded this chapter with a discussion of the practical conservation application of using this census technique in other parts of Africa, particularly where historic lion home-range data exist.
In Chapter 3, I used the same spatially explicit capture recapture models on data collected from 74 remote camera traps set across the QECA to assess the population densities of African leopards and spotted hyenas in this savannah park. We surveyed the northern, and southern sections of the QECA, and estimated leopard densities to be 5.03 (range = 2.80–7.63), and 4.31 (range = 1.95–6.88) individuals/100 km2 respectively, while hyena densities were 13.43 and 14 individuals/100 km2. Estimates of hyena density were the highest recorded for the species anywhere within their range using SECR methods. I also suggested that the high hyena densities could be related to the evidence provided in Chapter 2 of African lion decline in the QECA. One hypothesis that could explain the inverse densities of hyenas and lions is that hyenas have experienced competitive release from African lions in the QECA. Similar findings have been reported in the Talek region of Kenya’s Maasai Mara, and Zambia’s Liuwa Plains. This chapter also provided the first SECR population estimates of leopards, and spotted hyenas anywhere in Uganda.
In Chapter 4 and Chapter 5 I addressed the most important threat to the existence of large carnivores: conflict with human communities, and their livestock. While conflict tends to dominate the narrative where large carnivores and humans co-exist, there can often be direct and indirect benefits to humans. In Chapter 4 I examined the ecosystem services provided to people by the Indian leopard Panthera pardus fusca, in Mumbai.The Sanjay Gandhi National Park (SGNP) is located in the city of Mumbai, India, and has some of the highest human population densities in the world. Large carnivores are known to control prey populations, suppress smaller carnivores, reduce parasite load in humans, and promote seed dispersal. However, this chapter is one of the first studies highlighting the ecosystem services provided by a large carnivore outside of a natural or protected system. I showed that leopard predation on stray dogs reduced the number of people bitten by dogs, reduced the risk of rabies transmission, and reduced dog sterilization and management costs. Our estimates showed that dog densities around SGNP (17.3/km2) were 40 times lower than four nearby urban informal settlements (688/km2) and were ten times lower than the citywide mean (160/km2). If it is, as we propose, leopards that are holding the dog population around the park at its current density, dog bites could increase from 3.6 bites/1000 people to 15.5 bites/1,000 people if leopards were to disappear. As over 78% of dog bites in Mumbai require treatment, and 2% require rabies post-exposure vaccination, the treatment costs could reach as high as US$ 200,000 per year (compared to ~US$ 42,500 currently). As development pressures are threatening the region’s leopards, this work shows the potential costs of their local extirpation.
Chapter 5 assesses the landscape-level correlates of livestock attacks by two large carnivores, the spotted hyena, and African leopard in the cattle and sheep/goat farms bordering Lake Mburo National Park, south-western Uganda. I also make suggestions on how to improve the sustainability of a voluntary financial compensation scheme run by a local lodge (the Mihingo Conservation Fund) aimed at alleviating persecution of these species. I used ten years of depredation events to investigate the importance of seasonality and landscape features (ie. terrain ruggedness, proximity to roads, water, human settlements, and vegetation density) on livestock attack probability. I also examined the current costs of the compensation scheme of reported attacks. I showed that most livestock attacks in this region were caused by spotted hyenas, both predators killed at night, did not exhibit seasonal patterns in depredation, and attacks were owed to poorly fortified bomas (82% of leopard attacks and 64% of hyena attacks were made inside bomas). Attacks were also made near human settlements, close to the national park border, and in areas of rugged terrain. The compensation fund made more gross income from tourism activities than was paid in compensation in most years, but compensation costs had to be subsidised by the lodge because the funding was also used in other community development projects (eg. building of a school, and paying children’s school fees).
Chapter 6 of this thesis built upon the sub-theme of Chapter 5, funding of carnivore conservation measures and created a roadmap for a recently proposed idea of a threatened wildlife imagery royalty to stem the large budgetary shortfalls facing large carnivore conservation. The idea of a threatened species imagery royalty was proposed in two recent papers, Good et al. (2017) and Courchamp et al. (2018). I built upon these and discussed how such a royalty could be implemented, explored several legal avenues for its application, and also showed its potential scale in leveraging funding. The creation of a national law which charges a royalty from corporations using the imagery of their threatened wildlife, and a “Fairtrade” equivalent held the most promise for the development of a wildlife imagery royalty. Indeed, articles 3 and 6 of the Convention on Biological Diversity (CBD) encourage sovereign states to ensure activities within their jurisdiction and control do not damage the environment of other states. Similarly they are encouraged to develop national strategies, plans or programs for the conservation and sustainable use of biological diversity. The funding that could potentially be leveraged from a wildlife imagery royalty is immense. I used large felids as a model group to show that the relevant 14 companies on the Forbes 2000 list alone could generate US$ 202 million–2.02 billion if they paid 0.1-1% of their profits in royalties.
My thesis addressed an important but often overlooked component of estimating large carnivore populations, the use of population state variables in informing conservation status. The use of animal movement, sex-ratio, and density information has wide application that transcends large carnivores. My assessment of leopard-dog interactions, and the potential implications for humans, was one of the first examples in the literature of the potential benefits a large carnivore may have to humans. The assessments of compensation and wildlife imagery royalties have important consequences on better managing and also leveraging funding for the conservation of large carnivores and other threatened, enigmatic species.