Preliminary Survey of Habitat Use by Sciurus vulgaris orientis in a Natural Forest of Hokkaido Island, Japan

The Eurasian red squirrel Sciurus vulgaris Linnaeus, 1758 is widely distributed in the northern part of Eurasian Continents, Sakhalin Island (Russia), and Hokkaido Island (Japan) (Gurnell and Wauters 1999; Wilson and Reeder 2005). The distribution area of this squirrel is widest of all the world's squirrel species (Gurnell 1987). In Russia, this squirrel occurs in boreal coniferous forests consisting of larch (Larix), pine (Pinus), and spruce (Picea) (Lurz et al. 2005). The Hokkaido population of the Eurasian red squirrel is regarded as an endemic subspecies： S. vulgaris orientis (e.g., Imaizumi 1960). This subspecies occurs from low-lands to mountains (1,650 m) in Hokkaido (Takaragawa 1996). Ecological characteristics of S. vulgaris orientis living in forests isolated by agricultural and urban areas are reported (Lee and Fukuda 1999; Lee 2001, 2002). In urban areas, this squirrel frequently feeds cones of Pinus koraiensis (Lee 2002), which was introduced to Hokkaido by human activity (Maeda 1970; Miyaki and Miyaki 1980).