AfriCat’s Cheetah Rehabilitation project was initiated in 2000 and aimed to give some of AfriCat’s captive cheetahs (Acinonyx jubatus) the opportunity to return to their natural environment.
Between 2000 and 2018, 53 former captive cheetahs were released into the 200 km2Okonjima Nature Reserve. Besides reducing the number of cheetahs in captivity, the project aimed to assess whether rehabilitation is a successful instrument of conserving an endangered population. The majority of all rehabilitated animals were individuals rescued from farmland who spent a significant amount of time in captivity prior their release. Age upon release varied between 10 months and 8 years.
The Okonjima Nature Reserve (ONR) functioned as release site for all rehabilitated cheetahs, who were fitted with VHF radio collars to enable regular post release monitoring. The ONR is surrounded by a 96 km long electrified perimeter fence and is bordered entirely by commercial farmland and harbors a high density of naturally occurring leopards Panthera pardus and brown hyenas Hyaena brunnea. Three spotted hyenas Crocuta crocuta were introduced into the reserve in 2008.
The mortality rate of all cheetahs released between 2000 and 2018 into the ONR amounts to 76% with almost half of the individuals dying during the first year post release. 76% of all released cheetahs died during a certain stage of their rehabilitation process. The majority of animals (42%) died during their first year post-release. Interspecific killing accounts for 71% of all mortalities. Thereby, interspecific killing by leopards accounts for 81% of all mortalities, followed by spotted hyenas (8%). In 11% of all cases the source of predation could not be determined. Fatal injuries sustained during hunting was the second most common source of death (13%), followed by disease (11%) and other factors (5%).
Within the last years the leopard and brown hyena population in the ONR has increased steadily expanding the pressure on other carnivores like cheetahs with regards to home range and dietary overlap.
Fencing becomes a more and more increasingly critical tool in the future of large carnivore conservation. However, effective fencing restricts natural dispersal patterns and causes differences in ecology and behavior when compared to free-ranging carnivores. Although we proved that leopards are able to overcome the surrounding fence and move in and out of the ONR if intraspecific competition becomes too high, the high density of leopards in the reserve remains stable.
The high density of leopards in particular and the resulting strong overlap of home ranges between leopards and cheetahs are contributing to the high rate of interspecific competition and thus, mortality rate of cheetahs in the reserve. Predator-avoidance strategies such as natural large ranging patterns and the utilization of hunting grounds in areas of low predator occurrence are difficult to implement due to the fence restricted useable area. With the creation of more open plains in the reserve over the past years, we have hoped that we could achieve a more distinct separation between leopard and cheetah habitat use and thus, decrease the encounter rate of the two carnivore species. Due to the fact that the anticipated success failed to appear, the AfriCat Foundation reached the decision that the Okonjima Nature Reserve with its high leopard population will no longer be used as a release site for rehabilitated cheetahs. After 18 years of rehabilitating cheetahs into the ONR we have come to the conclusion that rehabilitation can be a successful tool in conserving cheetahs, that cheetahs are able to adapt to different environments and are able to learn how to survive in the wild and become sustainable hunters. Unfortunately, the increasing pressure of higher level carnivores like leopards and brown hyenas in an enclosed ecosystem, makes the ONR a more and more unsuitable place in which cheetahs can thrive.
Which leaves us with the question of what is the fate of those cheetahs currently living their lives in captivity waiting for their second chance in the wild? The choice of release sites for rehabilitated cheetahs are sadly very limited as the majority of them grew up in captivity and thus, are habituated to people to a certain degree which makes them unsuitable for a release onto farmland where a high percentage of Namibia’s cheetahs are most successful due to the lower number of the larger predators like leopards and hyenas. Most other conservation-minded, non-hunting private reserves in Namibia don’t have the capacity to release or reintroduce cheetahs due to porous and unmaintained fences and the large spatial requirements of cheetahs. Post release monitoring is as a key component in the field of wildlife rehabilitation. Unfortunately, the implementation of post release monitoring methods are expensive and therefore often get neglected, due to the lack of sufficient funds and manpower, which results in the unknown fate of many rehabilitated study animals. To evaluate post-release success and survival and to assess rehabilitation of former captive carnivores as a tool of conservation efforts, an effective monitoring programme of those carnivores needs to be implemented and conducted. Until more protected areas designated for the protection of cheetahs become available, education, human-wildlife mitigation and the creation of a cheetah positive mentality are the most powerful tools when it comes to the future survival of cheetahs in Namibia.