By Desiree Andersen, 20th April 2021
Asiatic black bears Ursus thibetanus are native to 20 countries across Asia, including the Republic of Korea (South Korea). They are categorized as Vulnerable on the IUCN Red List and are threatened by habitat loss, hunting and bile farming. Following decades of decline from poaching for medicinal purposes, eradication during the Japanese occupation, and habitat destruction, the species was extirpated from South Korea by the 1990s. In 2004, the South Korean government started a reintroduction programme in Jiri Mountain National Park. The reintroduction has been successful, with bears now populating the National Park and even dispersing into forests to the north. However, the National Park’s bear population now appears to have reached carrying capacity, raising several concerns. How many bears can be sustained in the National Park and the country as a whole? How should the government move forward with the reintroduction programme? Should the population in the National Park be supplemented? How do we make sure we take into consideration habitat suitability and connectivity? Can the bears repopulate the country without further interference, or should a second reintroduction programme be implemented in another part of the country?
Asiatic black bear Ursus thibetanus at the Species Restoration Technology Institute at Jiri Mountain National Park in South Korea. Photo: Desiree Andersen
We attempted to answer these questions using ecological niche modelling combined with population simulations and landscape connectivity mapping. Our aim was to find suitable bear habitat throughout South Korea, estimate population sizes at equilibrium for both the National Park and the whole country, and identify corridors for bear movement between habitat patches. After interpreting these models, we concluded that although the reintroduction in Jiri Mountain National Park is successful, there is still work to be done if the bears are to be restored nation-wide. Besides working to maintain the current population, it is vital that the government establishes and protects habitat and wildlife corridors throughout the country, so the bears can survive and move freely, and implement a second reintroduction, translocating some individuals to Seorak Mountain National Park (or nearby in the north-east of the country).
Population simulations of Asiatic black bears in South Korea for three scenarios: A) in Jiri Mountain National Park; B) in all of South Korea without a second reintroduction; and C) in all of South Korea with a second reintroduction. Note: one time step represents 2 years (one life-stage phase of a bear). Photo: Desiree Andersen
Without a second reintroduction, the black bear will not be fully restored to South Korea in our lifetimes. The population will remain at c. 230 individuals, whereas we estimate that the country could support a total of c. 1,440 bears. Restoring a habitat matrix that promotes connectivity will be vital. With a growing population, bears will start to disperse in the search for territory, but dispersal can only happen if suitable habitat is connected by suitable habitat corridors.
One individual—an adventurous young male known as KM-53—has already dispersed from the Park multiple times. This included an incident in which he was hit by a bus, suffering a broken leg. The route this bear took validates our connectivity mapping, as his path exactly followed one of our modelled pathways. This bear’s story shows the increased need for wildlife corridors, to prevent casualties and to allow bears to move freely across the country.
Left: habitat core areas and dispersal corridors for Asiatic black bears in South Korea overlain with motorways and medium- to high-usage roads, road tunnels and wildlife crossings. Photo: Desiree Andersen. Right: Current road crossing conditions around Jiri Mountain National Park (from Borzée et al., 2019, Photo: Amaël Borzée)
Of course, as with the reintroduction of any large carnivore, the government will need people to be supportive. Since the start of the programme there have been instances of negative interactions between people and bears. Bears with a penchant for honey attack hives, and people set traps that can be fatal for bears. It seems, however, that these problems can be mitigated by installing electric fences around areas where bears shouldn’t be and by educating the public about the benefits of species restoration. The government has already successfully marketed the Asiatic black bears of Jiri Mountain National Park as a local and national mascot, bringing the species closer to being accepted by the public. We hope our research will help secure a long-term future for black bears in South Korea.
Habitat core areas and dispersal corridors, for Asiatic black bears in South Korea (left), and in Jiri, Deogyu and Gaya Mountain National Parks (right), with the dispersal route taken by a subadult male (Borzée et al., 2019). Photo: Desiree Andersen
Borzée, A., Yi, Y., Andersen, D., Kim, K., Moon, K.-S., Kim, J.-J. et al.(2019) First dispersal event of a reintroduced Asiatic black bear (Ursus thibetanus) in Korea. Russian Journal of Theriology, 18,1.
The open access article Use of a spatially explicit individual-based model to predict population trajectories and habitat connectivity for a reintroduced ursid is available in Oryx—The International Journal of Conservation.
