First attempt at rehabilitation of Asiatic Black Bear cubs to the wild in Thailand

Abstract

Returning orphan bear cubs to the wild can benefit bear welfare and conservation but is hindered in Asia by the scarcity of documented experience. We experimented with rehabilitation of two Asiatic Black Bear cubs in Thailand using the assisted method of soft-release. We raised the 5-month old cubs for 11 months with minimal human contact in a remote enclosure in high quality habitat, letting cubs out periodically to walk with caretakers in the forest. The caretakers acted as surrogate mothers, allowing cubs to safely acquire foraging skills and familiarity with the forest. Supplementary feeding resulted in the cubs’ rapid weight gain (average 157g/day), faster than would occur in the wild. Faster growth allowed the cubs to be released sooner, reducing the likelihood of long-term habituation. After three months of rehabilitation, the bear cubs started showing signs of being wary of the caretakers (e.g., cautious when we approached their enclosure) and their focus during walks switched from play to foraging. After seven months they began to spend nights away from their enclosure, thus declining the supplemental food. This sequence and timing of increasing separation and independence from people matched other assisted soft releases in the region. The cubs went missing in month 12, shortly before planned collaring and release. They were seen together 2.5 months later on a fruiting tree and ran away when approached. Assisted soft releases might be a promising option for bear rehabilitation in Asia but more data are needed to evaluate their effectiveness relative to other methods. This method affords direct observations of bears in the wild that can augment our knowledge of bear behavior and ecology.

Revisiting the 4 R’s: Improving post-release outcomes for rescued mammalian wildlife by fostering behavioral competence during rehabilitation

“…Testable interventions to foster a diverse repertoire of behavioral skills include designing forested enclosures with enrichment like deadfall logs, climbing structures, and puzzle feeders; and exposure to complex forest environments during critical developmental stages. Forest walking-the practice of caregivers accompanying rescued cubs into unfenced, forestedhabitat to expose them to their natural range-is an approach to behavioral training that has been successful for multiple bear species (Fredriksson, 2005;Ashraf et al, 2008;Steinmetz et al, 2021). Leading indicators of efficacy include increased exploratory behavior, refuge seeking in trees, and increased behavioral diversity.…”