Gliding on the Edge: The Impact of Climate Change on the Habitat Dynamics of Two Sympatric Giant Flying Squirrels, Petaurista elegans and Hylopetes phayrei, in South and Southeast Asia

South and Southeast Asia are considered biodiversity hotspots, yet they face escalating threats from deforestation and climate change. This study evaluates the suitable habitat extent of two sympatric flying squirrels, Petaurista elegans and Hylopetes phayrei, using ensemble distribution models based on the climate-only model (COM) and habitat–climate model (HCM) approaches. The results indicated severe habitat loss, with suitable areas comprising only 1.56–1.66% (P. elegans) and 0.22–2.47% (H. phayrei) of their estimated extent of occurrence. Within IUCN-defined ranges, the suitability for P. elegans was 28.25% and 30.04%, while H. phayrei showed 2.86% and 32.39% in terms of the HCM and COM, respectively. The analysis further revealed habitat fragmentation, reduced patch size, and edge complexity, with future scenarios predicting increased isolation. These results highlight the urgent necessity for region-specific conservation strategies focusing on habitat recovery, connectivity, and transboundary cooperation. The recommended actions include genetic studies, corridor analysis, and field validation. This research provides critical baseline data to inform integrated, multi-stakeholder conservation planning across South and Southeast Asia for the long-term persistence of these vulnerable flying squirrel species.