The incredible distances that leopards are secretly travelling across the Overberg, including through the Nuwejaars Wetlands Special Management Area (NWSMA), have been captured in a new study.
The research, titled ‘Leopard dispersal across a fragmented landscape in the Western Cape, South Africa’, was recently published in the African Journal of Ecology. The study was led by Anita Wilkinson, senior researcher at the Cape Leopard Trust (CLT). Erica Brink and Eugéne Hahndiek, Conservation Managers of the Nuwejaars Wetlands SMA, are co-authors on the paper. Other authors include Mike Fabricius (affiliated with the Walker Bay Fynbos Conservancy and Grootbos Foundation), Rebecca Garbett (Panthera) and Dr Kathryn Williams (CLT Research & Conservation Director and Honorary Research Associate at Durham University).
The movements of four male leopards were captured on camera traps in the Overberg by four different conservation organisations, including the NWSMA, over a period of six years. The CLT used pattern recognition algorithms to match sightings of these individuals across datasets. Dispersal distances of the four ranged from 35 km to 112 km from the origin to the destination data points.
This is believed to be the first study reporting on the use of camera trap data to reveal dispersal in leopards.
Here’s how they moved across the landscape:
- A male leopard, called AM014, who was first recorded over a period of four days as an adult in July 2017 in the NWSMA, was subsequently detected 62 km eastward. He was captured on cameras in the De Hoop Nature Reserve in November 2020. Between September 2021 and January 2022, he was again seen on camera traps in the Denel Overberg Test Range.
- Littermates known as AM009 and AM010 were first recorded as sub-adults in February 2019 in the Walker Bay Fynbos Conservancy. AM009 was later recorded 103 km eastwards in the De Hoop Nature Reserve late in 2020. AM010 moved just 35 km eastward, where he stayed between August 2021 and January 2022.
- The final male, AM015 was recorded at seven locations in the De Hoop Nature Reserve in October 2020. Nearly two and a half years later, he was recorded 112 km westward, close to the Walker Bay Fynbos Conservancy.
Above: AM014 was first identified in the NWSMA in 2017, as captured in the Facebook post included above. It was then photographed in 2021, as shown in the two photos above, in the Denel Overberg Test Range.
According to the authors, “Evidence of these four male leopards traversing large distances in a highly modified and fragmented landscape affirms leopard adaptability and resilience on mixed-use agricultural land outside of protected areas and reveals that functional connectivity is still possible locally.”
Dispersal is a vitally important aspect of leopard ecology to prevent inbreeding, lessen competition and promote gene flow.
The authors write, “We caution that this evidence of successful dispersal should not lead to complacency about the population status but rather ignite a concerted effort to maintain and further enable a functionally connected landscape for this umbrella species.”
Above: Leopards continue to be photographed in the NWSMA, as well as some of their prey species, such as Bushbuck.
Leopards in the Overberg face many threats
Leopards are classified as Vulnerable on the International Union for the Conservation of Nature Red List of Threatened Species.
They face numerous threats, from habitat loss and degradation, to direct persecution due to livestock losses, and prey depletion through indiscriminate hunting with snares. These threats are compounded for leopards in the Cape Floral Kingdom, because they occur at low densities.
The leopards of the Cape are smaller and leaner than their northern bushveld brethren. They prey mainly on small antelope like klipspringer and grysbok, dassies and porcupine, whilst the larger leopard upcountry enjoys a diet of mainly impala, zebra and other larger buck.
This study brought partners affiliated to several organisations to work together. This collaborative approach emphasises the importance of inter-organisational communication and data sharing in conservation research, particularly when working with elusive and wide-ranging species such as leopards.
Above: These two photos were taken in the NWSMA, but they were not part of the research.
Images supplied by the Cape Leopard Trust and the Nuwejaars Wetlands Special Management Area.