Po-Jen Chiang, Formosan Wild Sound Conservation Science Center Co., Ltd.

The recovery of endangered Asiatic black bears (Ursus thibetanus formosanus) in Taiwan faces a unique challenge where natural habitats are closely knit with human settlements. Historically, accidental trapping was underreported. However, the 2022 implementation of a "no-penalty" reporting policy and Payment for Ecosystem Services (PES) brought "black numbers" of hidden mortalities to light. By shifting from blaming farmers to empathizing with crop protection needs, this approach saved at least 25 individuals. We evaluated the post-release efficacy of 12 such bears (15 release events) tracked between 2020 and 2025. Post-release survival was 75% (9/12); mortalities were linked to poor physical condition or renewed conflict. We documented three notable behavioral patterns. First, telemetry revealed near-zero movement for 1.5–2.5 months in winter for several individuals, suggesting dormancy; notably, camera footage from one bear visually confirmed tree-cavity denning. We hypothesize that Taiwan's steep altitudinal gradient mimics high-latitude conditions, triggering facultative dormancy. Second, movement scale diverged by age. While subadults established stable territories, one translocated adult male recorded a record-breaking home range of 803.2 km², traversing extreme gradients (70–2,500 m). Third, translocated adult males showed strong homing behavior. Despite releases up to 72 km away, they undertook extensive journeys to return to capture sites. This drive often channeled bears back through settlements, leading to recurrent conflicts as they raided poultry or cabins. Detailed movement analyses will be presented. Our findings suggest Taiwan is mirroring trends seen in Japan, where bears are expanding into town edges. While the "no-penalty" policy rescues bears, post-release management remains complex. Telemetry monitoring must serve as a real-time early warning system to support communities practicing coexistence.