Conservation of southern yellow-cheeked gibbons ( Nomascus gabriellae ) in the Anthropocene

The endangered southern yellow-cheeked gibbons ( Nomascus gabriellae ) occupy a fragmented habitat in Vietnam and Cambodia, with declining populations due to hunting, habitat loss and climate change. This study integrates population viability modelling with expert surveys to offer comprehensive insights into the species’ current state and its future prospects in a human-shaped world. Our modelling confirms the current population decline and suggests that a reduction in habitat loss and hunting is necessary to save this unique species from extinction. While declining habitat poses a long-term extinction risk, the current hunting rates threaten the species’ survival on the timescale of several decades. Crucially, large populations in Phnom Prich and Keo Seima Wildlife Sanctuaries and Cat Tien, Chu Yang Sin and Bu Gia Map National Parks play a key role in the survival of this species, as does the connectivity of these habitats. The expert surveys confirm the priority of protecting large populations and provide specific conservation actions for the case of Cat Tien National Park that are based on systematic stakeholder mapping. Altogether, this work assesses the population viability of southern yellow-cheeked gibbons in the Anthropocene and suggests conservation strategies that incorporate both ecological and social aspects.