Conservation of severely fragmented populations: lessons from the transformation of uncoordinated reintroductions of cheetahs (Acinonyx jubatus) into a managed metapopulation with self-sustained growth

Abstract

We document and evaluate the use of metapopulation management to conserve a declining population of 217 cheetahs in 40 subpopulations. Metapopulation management resembles a natural metapopulation, but dispersal success, demographic rescue effects and genetic viability are enhanced by moving suitable individuals to selected habitat fragments. Unfortunately, history and results of metapopulation management are rarely published. Cheetahs, extirpated from 85% of South Africa, were reintroduced from Namibian and South African ranches into fenced reserves. During 1965–2009 343 cheetahs were reintroduced, yet reserves held only 289 in 2009. Then translocations of free-roaming cheetahs were halted, and numbers dropped to 217 on 40 reserves by 2012. A metapopulation project was launched, and key conservation problems indentified from interviews and records. Thirty-five percent of reserves had no breeding cheetahs, 13% were inbreeding, fence quality was erratic, 3% of cheetahs were sold into captivity annually, and 28% of cheetah mortalities were anthropogenic. Lions accounted for 31% of mortality, perhaps elevated by lion-inexperienced cheetahs and high lion densities. These problems were addressed, and cheetahs were translocated between reserves. Although the median reserve size was only 125 km2 holding four cheetahs, and 80% of reserves were privately owned, in 6 years the metapopulation grew by 51% to 328 cheetahs on 51 reserves, while genetic diversity was managed and monitored. Thus, using metapopulation management, low density species and associated key processes, including carnivory or mega-herbivory, can be conserved in relatively small reserves in regions with dense human populations precluding natural gene flow.