Natural Forest Clearings Enable the Persistence of Stable Spotted Hyena Populations in Congo Basin Rainforests

Abstract

Spotted hyenas (Crocuta crocuta) are a large carnivore species known to range across broad savanna regions of sub-Saharan Africa. Although hyenas have occasionally been observed in rainforest habitat, they have been considered largely transient through these ecosystems. Odzala-Kokoua National Park (OKNP) in the Republic of Congo is known to harbor a resident hyena population in the forest-savanna mosaic region of the park, and while there have been observations of hyenas at large natural clearings called bais in the park's rainforest regions, these individuals have been assumed to be transient rather than representing a persistent rainforest population. We used more than 5 years of camera trap images of hyenas and their prey, 4 months of hyena GPS telemetry data, and remote sensing imagery of habitat to quantify the presence, distribution, and drivers of hyena occurrence at 10 bai complexes across OKNP. We found evidence of a perennial, stable hyena population in the rainforest, with hyena presence being positively associated with increased availability of large prey and open-canopy area in the surrounding landscape. Our results suggest that hyenas can persist in rainforest ecosystems by taking advantage of small patches of open-canopy habitat (i.e., bais) that support sufficiently large populations of preferred prey species. Our findings reveal that spotted hyenas exhibit remarkable behavioral flexibility in their habitat use and suggest that current distribution maps for the species be extended to include the forested regions of OKNP and possibly beyond.