Back to Search Start Over

The status and behavioural ecology of large carnivores in a human-impacted miombo woodland

Authors :
Davis, Robert S.
Publication Year :
2021
Publisher :
Nottingham Trent University, 2021.

Abstract

Decline in global carnivore populations has led to an increased demand for the assessment of carnivore densities in understudied habitats and the use of robust survey techniques to obtain these estimates. Furthermore, growing levels of anthropogenic disturbance can alter community structure and disrupt carnivore guild dynamics, thereby risking further population decline. This thesis examines the population status and intraguild dynamics of large carnivores in Kasungu National Park (KNP), Malawi. KNP is an example of a protected area that has experienced large-scale reductions in both carnivore and prey populations, whilst the miombo woodland of KNP has been identified as a habitat lacking baseline data on large carnivore density and behavioural ecology. Consequently, KNP is a novel site to 1) produce robust population estimates from an understudied habitat, and 2) improve understanding of niche partitioning strategies in a modified carnivore guild. Using the spotted hyaena (Crocuta crocuta) as a model species, Chapter Two reviews the current survey methodologies for estimating the population density of large carnivores. I advocate the wider application of spatial capture-recapture (SCR) techniques to estimate spotted hyaena density and provide recommendations for adopting these methods. In Chapter Three I provide a summary of the decline in protected area health and large carnivore populations in Malawi, before providing an overview of KNP and the sites' importance to regional conservation efforts. I build on this in Chapter Four, using camera trap surveys and SCR modelling to estimate leopard (Panthera pardus) and spotted hyaena density in KNP between 2016 and 2018. Using a novel spatial partial identity model (SPIM), I also address the issue of uncertainty in individual identification from camera trap data. Density estimates were low across survey years, compared to estimates from sub-Saharan Africa, for both leopard (1.9 ±0.19 SD adults/100km2) and spotted hyaena (1.15 ±0.42 SD adults/100km2). In addition, the presence of lion (Panthera leo) and wild dog (Lycaon pictus) is limited to dispersing individuals, highlighting the degradation of the protected area and the wider loss to the carnivore guild in KNP. In Chapter Five, using a combination of co-detection modelling, time-to-event analyses, and temporal activity patterns from camera trap data, I examine the spatiotemporal dynamics of leopard and spotted hyaena in KNP. I find that detection of leopard and spotted hyaena is significantly associated with the detection of preferred prey and competing carnivores, increasing the likelihood of species interaction. In addition, female leopards display temporal partitioning from both intra- and inter-specific competitors, which may affect overall fitness and result in increased exposure to sources of anthropogenic mortality. Using scat analysis techniques, Chapter Six compares the dietary niche overlap, as a proxy for intraguild competition, of leopard and spotted hyaena in KNP. Results show that leopard and spotted hyaena share relatively high levels of dietary overlap (Pianka's overlap = 0.65), providing further evidence of the potential for interspecific competition between the two species. This study provides the first robust population estimates for leopard and spotted hyaena in KNP and evidence of a range of niche partitioning strategies adopted by large carnivores in a modified carnivore guild. The low population density estimates for leopard and spotted hyaena are a cause for conservation concern. These concerns are exacerbated by the mutual drivers of spatiotemporal behaviour, the high levels of dietary overlap, and low prey densities, which increase the risk of exploitation and interference competition and could have negative consequences for population demographics. Therefore, increasing prey populations will be essential to minimise levels of interspecific competition between large carnivores. In addition, continued monitoring of population density and intraguild dynamics will be critical for assessing the efficacy of ongoing conservation initiatives in KNP and other protected areas in Malawi under similar levels of anthropogenic pressure.

Details

Language :
English
Database :
British Library EThOS
Publication Type :
Dissertation/ Thesis
Accession number :
edsble.843834
Document Type :
Electronic Thesis or Dissertation