Stima della Densità del Leopardo nel Taï National Park utilizzando Modelli di Spatially Explicit Capture-Recapture

Monitoring large carnivore populations is crucial, in order to provide reliable density estimates that are fundamental in wildlife ecology, conservation, and management. African leopards (Panthera pardus) have lost most of their historical habitat range, due to hunting, habitat destruction, poaching or conflicts with humans. However, data scarcity remains substantial across much of the African continent. Taï National Park (TNP), Cote D’Ivoire, is the largest pristine primary forest of Western Africa, which hosts a complex ecosystem where leopard is the larger carnivore. Therefore, estimating leopard density in this area could be relevant for a deeper understanding of ecological processes and well-being of the forest. The objective of the present study was to estimate leopard density in Taï National Park, Cote D’Ivoire. 48 camera-traps (CTs) were deployed on forest trails in a 70 km² area, using a mixed opportunistic and standardized design, that maximize the probability to detect leopards, while keep sampling areas where no leopard presence was yet reported. For each leopard video, individuals were identified by their unique rosette pattern on the coat and sex was derived by genitalia. A maximum-likelihood based spatially explicit capture-recapture (SECR) statistical framework has been implemented to assess leopard density. 45 CTs recorded 123 leopard capture events in 2.201 trap nights. The identification process led to 21 individuals identified, 9 males and 12 females. Male leopards were detected twice the times (n = 82) compared to the females (n = 41) and had larger range of movement with a high level of overlapping between individuals. The final density estimate was 17.97 ± 4.02 individuals/100 km² (95% CI = 11.65 – 27.71). CTs effort (i.e. proportion of days with at least one record on trap-nights) and location (whether they were on trails or road) influenced the detection probability g0, that was estimated to be 0.032 ± 0.006. Sex impacts the spatial parameter related to home range size σ, where males estimate (σ = 1708 ± 135 m) was higher than females (σ = 913 ± 86). Taï National Park research area resulted to be a high-quality environment for leopards. Possible explanations are related to the availability of preys, lack of competition with sympatric carnivores, and conservation efforts to protect the area. Sex-related differences in spatial organization are consistent with previous studies. The high degree of home ranges overlap may be the result of the high population density and primary forest habitat constrains, that promote social tolerance among same-sex individuals. These results set a baseline for future monitoring and conservation of this species, providing an insight for a more comprehensive understanding of Taï National Park ecosystem dynamics.