抄録
1. As appears in Tables 1-2, the number of species and individual birds sighted in the census generally shows a decreasing tendency as the census was progressing from Seocheon area where the forest is suffering a severe damage by pine needle gall-midges, through Kochang area where forests are suffering an average affliction, to Muan area which suffered a severe forest damage but it now much recovered from the affliction.
In each of these areas, more species and individuals of birds are sighted in a red pine forest than in a black pine forest. In general, more species of birds are sighted in October than in November because of the arrival of transients, while in November large flocks of a few species of winter visitors arrive in the census areas for wintering showing a high population density.
2. Typically dominant species in the census areas are the 6 species of permanent residents-Great tit, Jay, Turtle dove, Crow tit, Yellow-throated bunting and Greenfinch; the 3 species of winter visitors-Siskin, Brambling and Golderest; and several species of transients such as Dusky thrush, Tristram's bunting and Chestnut bunting. These dominant species of birds have a feeding activity closely related to pine needle gall-midges. A survey of insectivorous birds previously conducted by Ko et al. in 1969 reports that the majority of these bird species feed on pine needle gall-midges also.
3. Jay is dominant in red pine forests and Greenfinch is dominant in black pine forests.
4. Early morning plot censuses usually sight more species and individual birds than plot census carried out later in the morning.
