Urban carnivores in Asia: survival, occupancy and conservation

Song, Yating (2024). Urban carnivores in Asia: survival, occupancy and conservation. University of Birmingham. Ph.D.

Preview

Song2024PhD.pdf
Text - Accepted Version
Available under License All rights reserved.
Download (14MB) | Preview

Abstract

Increased urbanization has led to significant changes in land use types and landscapes, resulting in substantial negative impacts on biodiversity. This thesis aims to analyze which urban environmental and biological factors affect the survival and occupancy of urban carnivores in Asia and how to develop corresponding habitat connectivity programs to restore carnivore populations.
Chapter 2 investigated the potential for carnivore survival and presence in different Asian cities through a literature search. The effects of different urban environmental variables and species' physiological traits on urban carnivore survival were assessed. Chapter 3 compares leopard cat occupancy in two cities, Shenzhen and Hong Kong, by camera trapping, and patterns of occupancy variation were assessed according to different urban environmental factors. Chapter 4 investigated the distribution range and temporal activity patterns of leopard cats in Shenzhen using kernel density estimation. The spatiotemporal distribution pattern overlap of humans, domestic cats, and dogs, as well as the interactions and potential ecological niche competition between leopard cats and the different species, are explored. In Chapter 5, potential leopard cat ecological corridors in Shenzhen were simulated using the minimum cumulative resistance (MCR) model (with cost analysis), considering the distribution density of leopard cats and environmental factors such as topography and human and social factors.
Chapter 2 found that the percentage of urban built-up area was the most critical factor affecting urban carnivore survival, with a significant coefficient of -0.5 in my regression model (p<0.05). Regarding physiological characteristics, the urban survival rate of non-diurnal carnivores was 28.4\% higher than that of diurnal carnivores. The urban survival rate of solitary carnivores was 45.1\% lower than that of group carnivores.
Chapter 3 found that the occupancy rate of leopard cats in Shenzhen was 18.8\% lower than in Hong Kong (p < 0.01). The number of leopard cats decreased with increasing distance from the road, and in Shenzhen, the occupancy probability of leopard cats was higher in agricultural areas (0.75) than in urban areas (0.35).
Chapter 4 found that the spatial overlap between leopard cats and humans, domestic cats, domestic dogs, and wild pigs was > 55\%. Regarding temporal overlap, leopard cats had the highest overlap with domestic cats, with peak activity times at 06:00 and 23:00, 3-4 hours later than the peak activity times of domestic cats (02:00 and 20:00).
In Chapter 5, combined with the estimated spatial extent of core leopard cat density, this study proposes 118 potential ecological corridors in Shenzhen to aid leopard cat migration. The 23 most important major ecological corridors were identified. The average width of the best corridors was 727 m, with a total corridor area of 97.7 \(km^2\) and an estimated total cost of RMB 55.74 billion.
This study increases our understanding of urban carnivores in East Asia, confirms the importance of natural habitats for urban carnivores, and provides evidence that will be useful for prioritizing carnivore species conservation, controlling alien species and human disturbance, and restoring carnivore habitat connectivity.
Based on the results of this thesis, I suggest conserving remaining native habitats, restricting the expansion of urban built-up areas (for example, by laws of "ecological red lines"), and giving priority to the conservation of heavy, nocturnal, and solitary carnivores. Increased surveillance and stern action against poaching are also needed. In order to avoid endangering wild predators, my results also suggest reducing the amount of stray cats and dogs in urban habitat regions. Additionally, recreational users' access to carnivore habitats has to be controlled in order to lessen the negative effects of growing human-wildlife distributional overlap. Finally, it is important to identify the hotspots where wildlife is most active in cities, as well as the key connecting corridors that these animals use through the urban matrix. Fences that point animals in the direction of ecological corridors should also be created. When building the corridor habitat, native plants should be useful, and managers should also pay attention to the quality of the vegetation.

Type of Work:

Thesis (Doctorates > Ph.D.)

Award Type:

Doctorates > Ph.D.

Supervisor(s):