Seasonal distribution and ecology of migrant bird populations by mist-netting and banding in Korea (I)

Abstract

Seasonal distribution and ecology of migrant bird populations were studied by mist-netting and banding primarily in the area of Kyunggi-do, Korea during 1963-1966.1. From 6 June to 25 June 1963, 99 birds of 3 species and 3 July 1964 to 31 December 1966, a total of 123, 242 birds of 124 species were banded in Korea. 196 (144 Returns) recoveries of 22 species have been reported in Korea (outside of banding sites) and 7 recoveries of 5 species from abroad.2. At Taenung, N. E. Seoul, Korea, 11, 680 birds of the Pied Wagtail and 9, 013 birds of the House Swallow were banded in pear orchards.a. Both Wagtail and Swallow are summer residents. Wagtail arrives Korea in the beginning of March and Swallows in early April and these gregarious species gather at night into large flocks to roost while juveniles maintain their post-breeding roosts in pear orchard from June to October until the time of Autumn migration.b. Both Wagtail and Swallow maintain their roosts in the same site but they exhibit different roosting behavior.c. The time at which the Wagtails and Swallows arrive and leave the roost in relation to sunset varies with length of day, weather, however, light intensity may remain the same.d. The Wagtail gathers around the feeding ground more than 20 kilometers from the roosting site.e. Some Wagtails and Swallows banded the previous year returned and roosted in the orchard. The fact that they repeatedly roost in the same areas suggest that after breeding some birds remain in the orchard and some of them migrate southward.3. During July 1964-October 1966, 78, 170 birds of 12 Emberiza species were banded primarily in Kyunggi-do.Emberiza rutila, Emberiza spodocephala, Emberiza tristrami and Emberiza aureola ornata are the dominant fall and spring migrants. In fall they prefer soy-bean, corn and especially millet fields while in spring they are mostly seen on wheat and barley fields. Emberiza rustica is the most abundant species during late fall and winter and they prefer open fields with bushes.Emberiza rutila migrates through Korea in May and from the beginning of August until the end of October. The sex ratio is 100 females to 155 males (11674_??_, 17761_??_). More males were caught than females each month except in September when more females were caught.Emberiza spodocephala migrates through Korean from the middle of April through the middle of May and from the middle of September through October.Emberiza tristrami migrates southward through Korea the first half of May and during October. the sex ratio is 100 females to 140 males (392_??_, 551_??_).Emberiza aureola ornata migrates through Korea during May and from early August until the end of October.Emberiza rustica migrates southward but some of them winter in Korea. The wintering period is from the early October until the end of April. The sex ratio is 100 females to 191 males (13, 450_??_, 25, 687_??_).Emberiza yessoënsis continentalis migrates to Korea around the middle of October. Some of them wander in Korea while some of them migrate southward. The wandering period is from the middle of October to the middle of February.Emberiza cioides is a permanent resident and breeds in great number in Korea. However, they migrate southward in large flocks during winter and northward during spring. The sex ratio is 100 females to 159 males (497_??_, 792_??_).Emberiza e. elegans is a resident and breeds in fairly small number in Korea, but they migrate southward in large flocks around the end of October and northward around April. The sex ratio is 100 females to 280 males (462_??_, 962_??_).Emberiza fucata fucata is a summer resident, arrives to Korea in the middle of April and most of them migrate southward in September.