Mapping the spatial configuration and severity of giraffe skin disease in Ruaha National Park, Tanzania

Giraffe numbers, have dropped by about 40% in the last 20 years, making giraffes a species of conservation concern. In the same period of time, a skin disease has been observed in numerous giraffe populations across Africa. The disease, commonly referred to as giraffe skin disease (GSD), manifests as lesions, wrinkled skin, and encrustations that can affect the limbs, shoulder or neck of giraffes. Giraffe skin disease may hinder movement causing increased susceptibility to predation. In chapter 1, I reviewed GSD cases from literature reports and surveying efforts of individuals working with giraffes in the wild and in captivity in order to compile a database of known GSD cases. I detected variation in the manifestation, prevalence and severity of GSD in sub-Saharan Africa and giraffe populations in captivity. In chapter 2, I used photographic capture-recapture surveys via road-based transects in Tanzania’s Ruaha National Park to develop a database of spatially-explicit giraffe images. I used WildID to process these photos for individual identification and fitted spatial capture-recapture models to predict the spatial configuration of giraffe abundance and GSD prevalence within the study area. My results indicated that >86% of the giraffe population showed signs of GSD, which is the highest prevalence of the disease in Africa. With vast areas of Sub-Saharan Africa still without information on GSD, researching the prevalence and conservation impacts of this disease should be a priority. I also discuss the implications of this research for conservation of threatened species with an emphasis on disease ecology and vulnerability to predations, and more broadly, for wildlife conservation.

Last Updated
January 27, 2021
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2.77 MB