Photo © Vasti Botha
Translocating large carnivores to reduce human-wildlife conflict have historically failed, but recent improvements in satellite technology have enabled better monitoring and success. In their latest research, Power et al. report on the outcomes of repatriating 16 leopards across a South African province.
Leopards need little introduction. These large felids are ubiquitous across Africa and large parts of Asia. However, being so cosmopolitan means there is scope for conflict with humans and translocation is one of the non-lethal approaches on offer.
Most translocations of carnivores, especially outside officially protected areas, are to do with human-wildlife conflict mitigation, while less attention has been devoted to other ‘conflict-borne’ situations. By this, we mean a need to find homes for leopards obtained for forensic reasons, such as those that have been confiscated from illegal wildlife trade. Furthermore, there are situations where leopards have been left orphaned through human-wildlife conflict and require similar help.
The research follows on from similar work by Florian Weise and colleagues in Namibia, whose creative title: “A home away from home: insights from successful leopard (Panthera pardus) translocations’ summarises, in essence, what we as an agency had attempted to do. Simply put, getting leopards to stay put!
In South Africa, nature conservation is devolved upon the provincial government, meaning our work is an entity of the state mandated to maintain law and order. We were thus the first port-of-call and had the opportunity to receive a number of leopards from citizen tip-offs and genuine reporting of conflict-related leopards throughout the province.
Over a seven year period from 2014, we derived data from 16 different satellite collared leopards, which we released at varying distances, and used standard home-range metrics to assess home-range stability.
Since there are a number of ways to determine success when relocating carnivores, we focused our framework around the most recent studies on leopard translocations. The criteria for success in this framework are: surviving past one year (or until home-ranges stabilised), not homing back to their origins, home-range stability and reproduction.
We determined home-range stability using two-dimensional Home-range Overlap Indices (HROIs), and three dimensional Utilisation Distribution Overlap Indices (UDOIs), an approach developed specifically for leopards. The index values of the translocated leopards were then benchmarked against resident leopards, while we also looked at the leopards’ proximity to the release area using a scaled approach based on the leopard’s home-range. Although this method was at variance to the approach by Weise and colleagues, who reported a success of 67 %, our own analysis of their data would have also resulted in a similar reported success of 50%.
Recording mortality, and reproductive events, were relatively straightforward to carry out. There were two recorded cases of intraspecific mortality, which may have resulted from underestimating local leopard abundance, but it is worth reporting these cases where a newly incoming or already peripheral male may have been implicated, given the publication skew towards only reporting on successes. Another cause for concern during the study was wire snare-related mortality, which is high in parts of South Africa. Although it is stated that one needs to ameliorate all threats contingent to any reintroduction, this is not always logistically feasible.
We also found that disturbed landscapes tend to be more amenable to leopard settlement given there were more vacancies for leopard establishment, but they did come with attendant threats, such as wire snares from bushmeat poachers.
What has been most evident from our study was that translocation success hinges on proper design, planning and fully incorporating our knowledge of leopard biology. Therefore, without such considerations, haphazard translocation efforts could be every much as lethal as more direct control. Our study should be replicable with any solitary felid but we recommend translocation to be considered as a last resort after all biological and ecological factors have been considered.
Read the full research: “Repatriating leopards into novel landscapes of a South African province” in Issue 2:1 of Ecological Solutions and Evidence.