AfriCat Leopard Research 2019
During the last year the leopard research on Okonjima has focused on monitoring the existing leopard population to gain a detailed understanding of the spatial and behavioral ecology of leopards living in an enclosed reserve via the use of VHF collars and camera traps. – Dr Jenny Noak
Addressing and understanding the behavioral ecology of an apex predator within enclosed reserves is of utmost importance as it enforces the balance of a healthy ecosystem and has a valuable input in forming effective conservation and management strategies of fenced reserves and which findings can help manage carnivore population in comparable reserves.
A density of 14.5 leopards/100 km2 in the Okonjima Nature Reserve is among the highest recorded densities in Namibia, which shows that enclosed reserves have the potential to harbor high densities and individual numbers and highlights the importance of those reserves for the future survival of endangered species. A high prey abundance all year round, the absence of human persecution and the enclosed status of the reserve are believed to be the main drivers of the high leopard population in the Okonjima Nature Reserve.
Male leopards are occupying larger ranges than females. Based on camera trap data, average female home range size is 16.7 ± 9.04 km2 while male leopard home ranges are more than double the size with 40.03 ± 40.9 km2. Leopard ranges of the same sex overlap to a minimal extent, while a single male home range encompasses on average that of three to four females. Those results show that range size is dependent on resource availability and that leopards can cope with minimal space if sufficient access to food resources is ensured.
Home ranges of sub-adult individuals often tend to overlap with those of their parents. Even though leopards are generally asocial except at times of mating or when a female is accompanied by dependent offspring, in the last years we were able to observe a more social side of those solitary cats than previously expected: Male and female adult leopards often tolerate their already nutritrionally independent offspring on a kill and male leopards, who accompany females with their offspring temporarily.
In April 2019, the first GPS collar was deployed to our mature male leopard Sefu. The use of GPS collars will add an additional value to the existing research and conservation efforts as it will allow us to gain a more accurate understanding of home range and territory sizes as well as interspecific overlap in a reserve in which movements are largely prohibited by an all-surrounding electrified fence. Furthermore, special focus will be laid on dispersal behavior of sub-adult individuals and their movements upon independence in an enclosed reserve.
Below you can see the home range size of Sefu based on GPS data analysis. His home range size (95% KD) is 87 km2 occupying the complete northern part of the reserve; his core area (shaded area; 50% KD) is 24km2 which he occupies 50% of the time.