Naturalization of the Red-billed Blue Magpie in western Shikoku Island, Japan

Abstract

We reviewed observation records of the Red-billed Blue Magpie Urocissa erythrorhyncha (Corvidae) in Shikoku Island, Japan. This species of magpie, which is native to the Asian continent, is considered to have escaped captivity and been naturalized in western Shikoku. Thirty-three records of this species, dating from 2000 to 2017, were collected from Ehime and Kochi Prefectures. Two records of fledglings confirmed successful breeding. The magpie was observed mainly in secondary forest habitat sites, though they also used conifer plantation and farmland. These observations suggest that this naturalized species has become widely distributed in lowlands of western Shikoku Island.