洛東江河口의 鳥類

元炳旿,咸奎晃 慶熙大學校 1985 論文集 Vol.14 No.-

A survey of the invertebrate fauna of the sand bar in Nakdong delta and Yongwon-ri inlet, South Korea, was made, the count of migrating waders and waterfowl was taken, and the stomach contents of 5 Kentish plovers were analyzed. During the survey it was noticed that the commonest wader foraged near the water's edge and in shallow water during hightide. This may be correlated to the fact that their type of food is present in all these delta and inlet areas. The distribution and aggregation of waders and waterfowl shows an correlation to the distribution of their principal food species, and to other environmental factor such as the nature of the substrates and the availability of cover. The aggregating population of some waders confined to the remaining sand bar of Nakdong delta, e.g., Mujigae-dung, Galmaegi-dung, and Teama-dung, reflects changes occurring on a wide scale there. Although there may be a number of minor underlying factors, the fundamental cause for these changes in ascribed to the recent reclamation and construction of the barrage in the estuary.

러시아 南沿海州地域의 鳥類

元炳旿,李漢洙,朴眞永 경희대학교 한국조류연구소 1993 연구보고 Vol.4 No.-

본 논문은 1991년 6월 9일부터 1991년 7월 3일까지 러시아 연해주남부지역의 조류를 관찰한 결과를 종합한 것이다. 1. 본 조사를 통해 관찰된 조류는 총 106종 24,047개체이다. 2. 조사지역은 뻬레왈마을과 주변의 습지, 비낀강, 알찬강, 끄라스늬 야르, 한까호 및 까라뜨지나 자연보호지구 등지이다. 3. 뻬레호늬 뻬레왈 마을지역에서는 총 49종 296개체를 관찰하였으며, 우점종은 북방쇠찌르레기(Sturnus sturninus), 귀제비(Hirundo daurica) 및 바늘꼬리칼새(Chaetura caudacuta)등이다. 뻬레호늬 뻬레왈 습지지역에서는 총 32종 151개체를 관찰하였으며, 우점종은 붉은뺨멧새(Emberiza fucata), 큰부리까마귀(Corvus macrorhynchos) 및 검은딱새(Saxicola torquata) 등이다. 알찬강 지역에서는 총 31종 158개체를 관찰하였으며, 우점종은 청둥오리(Anas platyrhynchos), 깝작도요(Tringa hypoleucos) 및 큰부리까마귀(Corvus macrorhynchos) 등이다. 끄라스늬 야르지역에서는 총 28종 162개체를 관찰하였으며, 우점종은 북방쇠찌르레기(Sturnus sturninus)와 큰부리까마귀(Corvus macrorhynchos)등이다. 비낀강 지역에서는 총 33종 198개체를 관찰하였으며, 우점종은 호사비오리(Mergus squamatus), 찌르레기(Sturunus cineraceus) 및 파랑새(Eurystomus orientalis) 등이다. 한까호지역에서 관찰된 조류는 총 31종 951개체였으며, 우점종은 붉은부리갈매기(Larus ridibundus)와 흰죽지갈매기(Sterna leucoptera)이다. 까라뜨지나 자연보호지구에서는 총 12종 22,038개체를 관찰하였으며, 우점종은 팽이갈매기(Larus crassirostris)와 바다오리(Uria aalge)이다. 4. 비낀강 주변의 습지지역은 절종위기에 처한 조류의 번식지로서 매우 중요한 지역이며 국제적으로도 중요성을 지니는 지역이다. 따라서, 이 지역은 하루 속히 자연보호지구로 지정하여 영구보존관리토록 노력하여야 할 것이다. A birding trip to Primorskii region, Russia, was made from June 9 to July 3, 1991. The results of the birding trip are as follows: 1. A total of 24,047 individuals of 106 species was recorded. 2. The survey covered 7 major areas-Perebnui Pereval Village, Perebnui Pereval Wetland, Bikin River, Alchan River, Krasnii Yar, Khanka Lake and Karatzina National Reserve. 3. In Perebnui Pereval Village, a total of 296 individuals of 49 species was sighted, among which dominant species were Sturnus sturninus, Hirundo daurica and Chaetura caudacuta. In Perebnui Pereval Wetland, a total of 151 individuals of 32 species was sighted, among which dominant species were Emberiza fucata, Corvus macrorhynchos and Saxicola torquata. On the Alchan River, a total of 158 individuals of 31 species was sighted, among which dominant species were Anas platyrhynchos, Tringa hypoleucos and Corvus macrorhynchos. In Krasnii Yar, a total of 162 individuals of 28 species was sighted, among which dominant species were Sturnus sturninus and Corvus macrorhynchos. On the Bikin River, a total of 198 individuals of 33 species was sighted, among which dominant species were Mergus squamatus, Sturunus cineraceus and Eurystomus orientalis. On the Khanka Lake, a total of 951 individuals of 31 species was sighted, among which dominant species were Larus ridibundus and Sterna leucoptera. In Karatzina National Reserve, a total of 22,038 individuals of 12 species was sighted, among which dominant species were Larus crassirostris and Uria aalge. 4. The marsh areas around the Bikin River are internationally important wetlands supporting many endangered, species such as Mergus squamatus, Ciconia boyciana, Grus monacha, Porzana paykullii, Porzana pusilla, Turnix tanki, etc. Therefore, this area should be designated as a nature reserve and preserved for effective, continuous protection and management.

洛東江河口의 鳥類 : 河口堰과 土地埋立事業의 生態學的 影響評價 Essessment of Ecological Impact of Nakdong Estuary Barrage and Land Reclamation Project

元炳旿 慶熙大學校 1983 論文集 Vol.12 No.-

The Nakdong estuary is important wetland where some twenty species of waterfowl yearly visit for transit of migrate for wintering - including twelve species of wanders which are dominant, thirteen species of surface-water of inland-water ducks, geese and swans, three species of diving ducks and two species of seawater ducks. Among gulls, dominant are one transient species and two wintering species. Two species of cormorants also visit this estuary for wintering. Dominant among the important breeding species of waterbrids are a species of spot-billed ducks and another species of little terns. The estuary has now become the last and only remaining estuary for waterbirds in Korea and one the most important transit and wintering grounds in Northeast Asia for large groups of various waterbirds. The wetland on the estuary, which has his capacity for more than 20,000 waders and 30,000 waterbirds (about 75% of the entire species known in Korea) and which is located in their migrating route, is considered essential for their surviving. As we Know, the accepted ornithological criteria for assigning international importance to wetlands as propounded by the International Wetlands Conferences in Ramsar, Iran(1972) and Heiligenhafen, West Germany (1974) are: (ⅰ) the wetland should support at least 1% of the pupulation of one or more species of waders of waterfowl in an international flyway, In the present context this constitutes Europe and North Africa; or (ⅱ) the wetland should support totals of 20,000 or more wader and or more than 10,000 wildfowl of species. However, the number of the waterfowl and waders visiting the Nakdong estuary every year far exceeds the figures suggested above for wetland criteria in Europe or North Africa. Thus, the Nakdong estuary is regarded very much important both domestically and internationally. The decrease in the past twenty years in the number of waterfowl and waders migration to this estuary is largely due to the water pollution caused by industrial sewage and insecticides flowing into the Nakdong River and to the development of agricultural and resident areas within the estuary, which have encroached and impoverished habitats. For minimizing negative ecological impacts on wildfowl from the factors mentioned above and from the Nakdong estuary barrage and land reclamation projects, conservation efforts should be made for effective supervision and rational administration for nature conservation through scientific surveys and researches.

巨濟島 沿岸의 冬季鳥類調査

元炳旿,尹茂夫 慶熙大學校 1974 論文集 Vol.8 No.-

1. Four winter sea bird censuses were made along the off-shore coast of Geoje island, on the southeastern coast of the Korean peninsula, during 1971∼1974. 2. Relative abundance and dominance were culculated to make indices for relative density and abundance of each species. 3. Three census routes and the number of species were recorded, and crude density by number of birds per kilometer and hour were as fallows: 1) Gohyun-Sungpo-Sobyongtaedo-Changseungpo 1971 census……21.73/㎞, 188.90/h(1,587 individuals of 20 species) 1974 ceusus……42.01/㎞, 466.10/h(3,067 individuals of 22 species) 2) Gohyun-Sungpo-Sobyongtaedo 14.28/㎞, 123.12/h(543 individuals of 18 speices) 3) Gohyun-Changseungpo-Sobyongtaedo 12.96/㎞, 131.04/h(1,141 individuals of 16 species) 4. Of 6,120 birds of 48 species recorded, Black-throated Diver, Gavia arcticus, Black-tailed Gull, Larus crassirostris, Ancient Murrelet, Synthliboramphus antiquus, Black-necked Grebe. Podiceps caspicus, Velvet Scoter, Melanitta fusca. Red-breasted Merganser, Mergus serrator and Spot-billed Duck, Anas poecilorhyncha were recorded to be dominant species. 5. The unspoiled off-shore coast of Geoje island should be preserved for the wintering of sea birds.

새만금 유역에 도래하는 철새 현황과 서식지조성방안

원병오 한국농공학회 2005 韓國農工學會誌 : 전원과 자원 Vol.47 No.2

標識放鳥에 依한 韓國産 철새 集團의 季節的 分布와 그의 生態(Ⅰ)

元炳旿,禹漢貞,咸奎晃,田美子,尹茂夫 慶熙大學校 1967 論文集 Vol.5 No.-

實驗材料로 토기, 마우스 및 가물치를 使用하여서 致死至近量의 物理的 環境要因 (溫度, 重力, 電擊, 電離放射線 및 非電離放射線), 化學的 環境要因(無機이온) 및 生物學的 環境要因(媒質의 渗透壓)等에 依한 處理가 血液蛋白質의 電氣泳動像을 비롯하여 赤血球, 白血球, 헤마토크리트比, 血色素量, 赤血球脆弱性, 肝臟器官의 組織像 그리고 肝臟 및 腎臟器官重量等에 미치는 效果를 硏究調査하였다. 前記 致死至近量의 環境要因의 處理로 一般的으로 蛋白質代謝, 血液像, 肝臟器官의 組織像 및 肝臟器官重量等에 顯著한 變化를 招來함을 알 수 있었다. 總血淸蛋白質量의 顯著한 變化 및 알부민―굴로부린比의 變化等은 血液內의 渗透效果의 變化를 招來함을 示唆하여 준다. 血淸電氣泳動像의 變化는 前記 環境要因에 依한 處理로 因하여 蛋白質代謝의 異常 卽 肝臟機能의 異常을 招來함을 알 수 있다. 以上의 結果로 미루어 보아 致死至近量이 內的 및 外的의 物理的, 化學的및 生物學的 環境要因에 依한 處理로 因하여 血液蛋白質, 血液像 및 肝臟器官 等의 異常은 生體에 큰 損傷을 가져오며 아울러 生體의 生理的平衡에 有意性的인 變化를 招來한다고 思料된다. Seasonal distribution and ecology of migrant bird populations were studied by mist-netting and banding primarily in the ares of Kyunggido, 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, 11623 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 resident 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 Wagtaill 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 mat 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 and 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 Korea from the middle of April through the middle of May and from the meddle of September through October. Emberiza tristrami migrates southward through Korea the first half of May and during October. The sex ratio is 100 female to 140 males(392 ♀, 551 ♂). Emberiza aureola oruata megrates through Korea during May nd 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 mules (13,450 ♀, 25,687 ♂). Emberiza yessoensis continentals 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 meddle of February. Emberiza cioidos 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 f. fucata is a summer resident, arrives to Korea the middle of April and most of them migrate southward in September. Emberiza chrysophtys migrates southward through Korea in May and from September to October. Emberiza pusilla is a not uncommon transient during spring and autumn and some of it wanders during winter in Korea. Emberiza leucocephala leucocephala Known as a straggler based on the sex specimens but a rare winter visitor. It migrates southward through Korea and some of it wanders around the end of January to the middle of March. 4. Noteworthy records of 21 species observed by the authors and some new species in Korea are given, each with notes on banding and collection records-See text for each species. Observations were made on the feeding habits of nestlings of ten species, Lanius tigrinus, Butorides striatus amurensis, Fhnberiza f. fucata, Motazilla alba leucopsis, Oriolus chinensis diffusns. Accipiter nisus nisosimilis, Mierascelis amaurotis henssent. Garrulus glandarins brandtii, Accipiter solecnsis and Cyanopica eyamts Koreensis. The investigation was made in Kwangnung experimental forest, Kyunggido and the nearby open field by using collar method. Accipiter nisus nisosimiles, Microscelis amaurotis hensoni, Garrulus glandarius brandtii and Cyanopiea cyanus Koreenses are permanent residents and the other six species are common summer residents. The following is the food that these nestlings consumed. 1. Lanius tigrinus The food they consumed was animal matter Composes of; insect larvae-41.5%, insect adults-49.4%, spiders-7.69%, frogs-1.53%. The cicada, Gampsocleis ussuricnsis made up 33.8% of the insect larvae. The cricket, Platyplenra kacmpferi made up 35.4% of the adult insects. Only one species of spiders, Clubiona jucunda was seen, 7.69% of the food. 2. Butorides striatus amurensis The food was animal matters composed of; small freshwater fishes-18.57%, Ranidae-45.71%, others-5.71%. Twenty percent of the small freshwater fishes was Zacco platypus while Hemibarbus logirostris made up 14.28%. Among Amphibians, Rana n. nigromaculata included 22.8%. 3. Emberiza f. fucata The food was amimal matter; insect larvae-63.3%, adult insects-25.64%, others-12.78%, Since 48.1% of the food items was larvae of Pieris rapae, it is most useful for agriculture. 4. Motacilla alba larcopsis The food during their nestling period was animal matter compsed of; insect larvae-30.5%, adult insects-55.4%, spiders-13.9%. The commonest insect larvae were Odonata indet.-22.2%. The commonest adult insects were Syrphidae indet.-16.6%. Of the spiders Lyecsa sp. made up 12.1% and Lycosa astrigera-2.8%. 5. Oriolus chinensis diffusus The food was animal matter composed of; insect larvae-62.36%, adult insects-20.17%, others017.42%. It should be noted that from the initial time of its feeding until leaving it consumed Dendrolimus spectabilis, a noxious forest insect which made up 45.08% of the diet. Thus it is very useful birds eliminating noxious forest insects. 6. Accipiter nisus nisosimilis The food was animal matter composed of; small passerine birds-87.5%, Ranidac-12.05%. It consumed such forest birds as Paridae. 7. Microscelis amauretis hensani The food was primarily insect adults-79.65%, Mollusca-12.15%, vegetable matter-4.05%, insect larvae-2.70%. Araneina-1.35%. Homoptera was 43.35% of adult insects. 8. Garrulus glaudarins brandtii The food during its nestling pcriod was solely animal matter; insect larvae-38.80%, adult insects-28.90%, Araneina-24.87%, adult Amphibia-15.49%. Right afrer hatehing and until leaving its nest, Dendrolimus spectabilis-35.08%, Arancina-24.87%, Clubiona jueunda-6.43% were fed. Therefor 73.48% of the total food was noxious forestry insects. 9. Accipiter soloensis The food during the whole feeding period was primarily Rana n. nigroma-culata 89.09%, but small quantity of Platypleura Kaempferi 8.26%, was also fed. 10. Cyanopica cyanus koreensis The food was composed of; insect larvae-6.11%, adult insects-60.55%, Hyla arborea japonica 12.22%, vegetable matter-1.11%. Gampsocleis ussuriensis-23.39%, Platypleura knempferi-15.55%, and Hyla arborea japoniea-12.22% were the prefered food supplied during the whole feeding period.

흰눈섭황금새(Muscica narcissina zanthopygia HAY)의 생태-특히 번식경과와 육령기의 식습성

원병오,이경조,WON, Pyong-Oh,RHEE, Kyung-Jho 한국통합생물학회 1965 동물학회지 Vol.8 No.2

1. This report is on the outcome of observation made up the breeding process of Narcissus flycatcher, Muscicapa narcissina zanthopygia, using 15 ness-boxes at Seoul and Kwang Nung Experimental forest in 1964, and the relevant feeding habit was studied by the collar method of wrapping the necks of thenestlings for 50-60 minutes or more in some cases from 1963 to 1964. 2. The Narcissus flycatcheris a common summer resident throughout Korea arriving at the end of April. The earliest data of arrival of this species in Seoul, is April 26, 1964. They migrate southward from the later part of September to early part of October. 3. In a week after their arrival , they start to build nest after a brief courtship. Male and female prepare their nest ina nestboxes in 4 or 5 days. Nests are usually found in the moss, which provide definite frame-work. The inner side of the nest is usually composed of roots of Gramineae or leaves of pine, oak or other broad leave tree. 4. The laying period is generally from the later part of April to the middle of June : and the number of eggs laid is from 3 to 8 , therefore 5 in average : eggs are pink with traces of milky yellow blending of light auburn and orange red spots and chicken-egg-like in shape. 5.The incubation takes place for 7-12 days from the middle part of May to the middle of June, in the order of male and female . The hatching rate tends to increase in proportion to clutch size. 6. The feeding period usually lasts 15 days in average from the early part of June to the middle of July and the feeding urge tends to increase in proportion to brood size. 7. The animals invading into their nest-boxes are red ants, chipmunks, bees , barkbeetles and philippine red-tailed shirkes, etc. 8. On the basis of analysis covering 714 birds in 31 nests, the food they consumed during the nesting period of nestlings were mostly of animal matters composing of : insect larvae form-39. 88% insect adult form 36.26%, insect pupae-0.19%, spider-17.75% and other animal matters 5.92% , Besides a small amount of plant pieces were found . As to the insect larvae, Lepidoptera was the largest in the content followed by Hymenoptera , Orthoptera and Coleoptera. As to the insect adult, Diptera was the largest in the content followed by Coleoptera, and Hymenoptera. In view of forest protection, noxious insect was of 69.38%, useful insect 4.39%, and spider 17.75%. 9. The rich assortment of its food, the ability of acquiring various insect (adults as well as larvae), its destruction of great numbers of harmful insects , and its quick assimilation artificial nesting with the nest-boxes of 2.5-3cm entrance hole employed, allow us to conclude that the flycatcher may be successfully employed in the elimination of fores pests. The above results are only that part obtained near Seoul in the middle of Korea, however, if we would extend the scheme to other broad areas using similar techniques, the nest-boxes could not only be well used by the birds, but also it would help to prevent the increase of harmful. insects.

청딱다구리 Picus canus friseoviridis (Clark)의 繁殖經過

元炳旿,具太會 경희대학교 한국조류연구소 1986 연구보고 Vol.1 No.-

1973年 5月 19日부터 6月 30日까지 京畿道 楊州郡 榛接面 光陵林에서 청딱다구리 Picus canus griseoviridis의 繁殖經過를 調査하였다. (1) 孵化까지 7日間의 抱卵觀察에서 암수 어미의 둥우리 出入回數는 1日平均 3回였다. (2) 그러나 抱卵率은 1日平均 암컷이 45.88%, 수컷이 54.12%로서 수컷이 암컷보다 抱卵率이 높았다. (3) 孵化에서 離巢까지의 育雛期間은 24日이었고, 먹이를 물고 둥지를 出入한 回數는 1日平均 13回였다. (4) 育雛期의 어미의 在巢時間은 1日 平均 암컷은 47.98%, 수컷은 52.02%로서 수컷이 약간 많았다. (5) 育雛期의 成長率은 1日平均 全長이 6.98㎜, 翼長 4.23㎜, 尾長 2.92㎜, 體重 4.53㎜ 였다. (6) 育雛期의 食餌物은 개미의 卵이 大部分이었다. 개미類의 卵 95.32%와 成蟲이 2.08%였고 그밖에 昆蟲의 幼蟲 0.17%, 거미類 0.14%가 있었다. (7) 採餌地는 主로 70~80年生 老松들이 있는 곳이었으나 일부 混淆林 草地에서도 採餌했다. 抱卵期에서 家族期까지 같은 場所에서 採食하였다. (8) 勢力圈은 둥우리를 中心으로한 約 40m×25m 範圍의 西쪽 숲이었고 採食地는 勢力圈 밖에 있었다. (9) 勢力圈內 外敵이 侵入한 鳥類는 12種이었으며, 抱卵期 45.08%와 育雛期 54.92%로서 共히 侵入한 種에 對해서 防禦하였다. The reproductive success of the Grey-headed Green Woodpecker, Picus canus griseoviridis (Clark). The breeding biology of the Grey-headed Green Woodpecker, Picus canus griseoviridis was studied in Kwang-n??ng Forest, Chinch??b-my??n, Yangju-gun, Kyonggi-do, during the period of 19 May-30 June, 1973. 1. Until hatching there is a seven days period of incubation observed, and the pair of parents enter their nest an average of three times a day. 2. The incubation rate on an average day for a female is 45.88% while it is 54.12% for a male, and this fact indicates the incubation rate for a male is higher than for a female. 3. The period from hatching till leaving the nest (during the feeding period) is 24 days, and the percentage of parent's entering their nest is an average of 13 times a day for feeding purpose. 4. During the feeding period the female stays at the nest 47.98% of the time, and the male stays 52.02% of the time, so the male stays more time than the female. 5. The growth rate of the feeding period on a one day average shows that the total length is 6.98㎜; the wing length is 4.23㎜; the tail length is 2.92㎜; the weight is 4.53g. 6. The food items of the feeding period are mostly animal matters, and these items consist of 95.30% of Formicidae egg, 2.08% of Formicidae adult, 0.17% of Insect larvae, 0.14% of Spider, 0.04% of Snail, 2.10% of cherry and 0.16% of pine seeds. From this study, and eggs are found as their main foods. 7. The feeding ground in the majority of nest is found in a dead pine woods, which had from 70 to 80 years old, and also in the grassfield, and from incubation until fledgling periods it feeds at the same place. 8. The territory of the woodpecker had a 25×40m, with the nesting tree at center.

북한지역의 동불분포현황

원병오 북한연구소 1977 北韓 Vol.- No.64

九窟島 바다제비 Oceanodroma monorhis (Swinhoe)의 繁殖經過

元炳旿,李漢洙 慶熙大學校 1986 論文集 Vol.15 No.-

The reproductive success of Swinhoe's fork-tailed Petrel Oceanodroma monorhis(Swinhoe) was studied from late March to late September 1986 on Kugul Islet, natural monument No 341. an ocean bird-breeding site in Sinan-kun. Oho˘lla South Province (34˚04'N. 125˚7'E). 1. Kugl Islet in 135,200㎡, in which the area having Carer boottiana is 31,000㎡, the scrubland is 8,600㎡, the area having Artemisia scoparia and Miscanthus sinensis is 3,500㎡, and the rest is covered with rocks exposed. 2. The breeding density per quardrat (4m×5m)of Swinhoe's fork-tailed Petrel in the area having Carex boottiana was average 60.8±11.0 pairs (n=5) and in the rest of the areas of scrubland and Artemisia scoparia and Miscanthus sinensis was average 30.1±5.2 pairs (n=8). Thus, the area having Carer boottiana had average 30.7 pairs of Swinhoe's fork-tailed Petrel per quardrat more than the rest of the areas of scrubland and Artemisia scoparia and Miscanthus sinensis, and the density was significantly high in the former area (P<0.005) 3. The total number of Swinhoe's fork-tailed Petrel was estimated to be 112,600±15,030 pairs in 95% confidence limits. 4. The average measurements of Swinhoe's fork-tailed Petrel breeding on Kugul Islet were bill length 14.38±0.58㎜ (n=94), tarsus length 24.18±0.86㎜(n=94), wing length 156.8±4.67㎜(n=94), tail length 78.21±3.82㎜(n=94), and body weight 48.5±4.31g(n=93). 5. When incubating, male and female Swinhoe's fork-tailed Petrel parents regularly took turns, and the length of their incubation at a time was averaged 4.17±0.86 days(n=18). 6. The measurements of the egg were length 32.56±0.93㎜(n=17), width 24.52±0.58㎜(n=17) and weight 10.23±0.64g(n=16). 7. The food of Swinhoe's fork-tailed Petrel nestling was composed of fishes 52.6%, squids 31.5% and shrimps 10.1%. 8. Through sonogram analysis three different calls were distinguished; the call of warning, the call made when mating and flying, and the call made while taking rest. The formant frequency of the first two calls was 4 K㎐, and that of the third call was 2 K㎐. Each of the three calls was below 6 K㎐. 9. As for the daily activity of Swinhoe's fork-tailed Petrel, there was no difference in July between moonlight hours and dark hours, but in August their activity after the moonset considerably increased. However, their activity immediately after the storm on the 19th of August was remarkably decreased.