Abstract
The population of endangered species, Blakiston’s fish owl Ketupa Blakistoni, has been increasingly recovering with conservation activities. The next conservation target is to expand their distribution that currently concentrates in the eastern Hokkaido. In this study, we first built a static distribution model of the fish owl in the region where the owl has stable populations. Based on the static model, we projected the future range expansions of the owl using dynamic distribution modeling under the scenarios with varied conservation activities and land-use changes. The static distribution model suggested that the regions with large amounts of natural riparian forests and river length are suitable areas for the owl. Future projection of the owl ranges indicated that an increase in the breeding success would greatly contribute to the range expansion. It was also indicated that population dispersal from the eastern-most (Konsen) population is restricted, and that the existing populations are likely to expand the ranges into the central Hokkaido (Yubari Mountains). However, there were large unexplained variations in the static distribution model and large uncertainties in the projection of range expansion, suggesting that conservation activities should be flexibly planned according to the actual range expansion processes of the Blakiston’s fish owl.
