The ecology, conservation and management of Nile crocodiles Crocodylus niloticus in a human dominated landscape

Abstract

Nile crocodiles were extensively persecuted throughout much of the 20th century. The extinction of the species was only averted by the timely intervention of conservationists and by the beginning of the 21st century most populations had recovered. Many of the conservation measures designed to curb the original extinction threats remain unchanged and are now perceived by some to be outdated. The recovery of Nile crocodile populations has been accompanied by rapid human population growth and demands for freshwater resources. This phenomenon has resulted in a converging conflict crisis between Nile crocodiles and humans. The aim of this thesis is to (a) quantify the extent of human crocodile conflict (HCC) and (b) establish the implications for conservation and development. (a)The extent of HCC was assessed by (i) analysing losses incurred by local communities (ii) analysing the demographics of crocodiles in relation to human activities (iii) analysing the relationship between humans and crocodile prey species. Nile crocodiles pose a substantial threat to subsistence livelihoods whilst rural communities have significant negative impacts on crocodiles (i) Estimates suggest an annual loss of between ~255 and ~6864 cattle per year and damage to an estimated 71500 fishing nets per year in North Eastern Namibia. (ii) All crocodile size classes showed a negative relationship with people at the inter- and intra-river levels. (iii) Crocodile prey species showed a significant negative spatial relationship with cattle. (b) Conservation and management implications were assessed by estimating the spatial patterns of HCC explanatory variables on a continental scale. Protected areas are important for crocodile conservation. The use of crocodile habitat as boundaries for protected areas raises important questions relating to HCC.