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
ix
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.
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
ix
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.
Original language | English |
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Qualification | Ph.D. |
Awarding Institution |
|
Supervisors/Advisors |
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Award date | 31 Jul 2021 |
Publication status | Published - 1 Jul 2021 |
Externally published | Yes |