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Breeding Population and Habitat of Black-tailed Gulls (Larus crassirostris) on Nando Island, Natural Monument (천연기념물 난도에서 번식하는 괭이갈매기 개체군 및 서식 환경)

  • Kim, Miran;Kwon, Young-Soo;Nam, Ki-baek;Lee, Ho;Myeong, Hyeon-Ho;Noh, Hyung Soo
    • Korean Journal of Environmental Biology
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    • v.35 no.2
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    • pp.134-142
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    • 2017
  • Nando Island is reported as one of the biggest breeding colonies of seabirds in South Korea, and is protected as a Natural Monument. This study was conducted between July to November 2015, to investigate the breeding population of Black-tailed gulls and their habitat on Nando Island. We estimated the breeding population of Black-tailed gulls (Larus crassirostris) using nest density. The mean nest density of Black-tailed gulls was $0.51\;per\;1m^2$ ($0.51m^{-2}$), and the breeding population was approximately 26,760 individuals. The dominant vegetation was Echinochloa crusgalli and Agropyron tsukushiense var. transiens, which served as shelter and nest sites to Black-tailed gulls. The diet of Black-tailed gulls was mainly the fish, Japanese Anchovy Engraulis japonicas (48%). Other species which were found to breed on Nando Island were Streaked Sheawater (Calonectris leucomelas), Temminck's Cormorant (Phalacrocorax capillatus), and Swinhoe's storm petrels(Oceanodroma monorhis).

Population genetic structure and regional fragmentation of rare CO1 haplotypes of Black-tailed Gulls (Larus crassirostris: Laridae) in Korean Peninsula (한반도 괭이갈매기의 개체군 유전 구조와 희귀 CO1 유전자형의 지리적 파편화)

  • Jeong, Gilsang;Hwang, Bo-Yeon;Kwon, Young Soo;Jin, Seon Deok;Choi, Sunghoon;Kim, Miran;Choi, Hansu;Park, Jin Young
    • Korean Journal of Ornithology
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    • v.25 no.2
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    • pp.106-111
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    • 2018
  • The Black-tailed gull (Larus crassirostris) is one of the most common gull species in the Northeast Asia and classified as LC (least concern) in the IUCN Red List. The bird has become a useful indicator for marine environmental pollution and habitat disruption, since the human activities impacted marine environments. Here we show that the black-tailed Gull has 6 haplotypes and some rare haplotypes are locally limited implying that the bird may not disperse far. This study may be the first report on population genetic study of Black-tailed Gull in Korea and could be used as the baseline data for monitoring and genetic study on the bird as an environmental indicator.

Egg Retrieval as a Source of Nests with Supernormal and Mixed Egg Clutch in Little Terns Sterna albifrons (쇠제비갈매기 Sterna albifrons의 과산란 및 이종 알 혼합 둥지 생성 원인으로서 알 회수 행동)

  • Kim, Jeong-Hoon;Nam Hyung-Kyu;Fulton Graham R.;Yoo Jeong-Chil
    • Journal of Ecology and Environment
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    • v.29 no.6
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    • pp.545-550
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    • 2006
  • Ten supernormal clutches of little terns Sterna albifrons and seven clutches having mixed eggs by little terns and kentish plovers Charadrius alexandrinus were recorded during the breeding seasons of 2003$\sim$2005 at Ganwol lake, Hongsung-gun, Chungcheongnam-do, Korea. The frequency of egg retrieval by Little Terns was higher after the second egg laying regardless of the clutch size and incubation stage. The frequency of egg retrieval was high at all incubation stage. When experimental eggs were placed within 15 cm from the nests, the percentage of egg retrieval was highest (almost 100%). However the percentage dropped rapidly over 35$\sim$55 cm range and finally to zero at 60 cm distance. Little terns retrieved all kinds of eggs set near their nests regardless of its kind or size. This study suggests that egg retrieval by little terns may be a source of the nest with supernormal and mixed egg clutch observed in this species.

Studies on Plant Succession of Sand Bars at the Nagdong River Estuary I. Vegetation and Soil Environment (낙동강 하구 사주식생의 천이에 관한 연구)

  • Mun, Hyeong-Tae;Kim, Joon-Ho
    • Journal of Plant Biology
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    • v.28 no.1
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    • pp.79-93
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    • 1985
  • Plant succession and subsequent changes of soil properties were studied in sand bars at the Nagdong River estuary in Korea. By old maps, ages of sand bars such as Namusitdeung, Galmaegideung, Baeghapdeung and Ogryudeung were estimated about 10, 15, 25 and 60 years old, respectively. The dominance-diversity curves and plant species diversity indices among the sand bars showed increasing trend of stability from Galmaegideung toward Ogryudeung. The soil acidity, contents of organic matter and total nitrogen of soil increased significantly from Galmaegideung toward Ogryudeung. The order of successional degree among the sand bars on the basis of the number of plant species, the results of vegetation analysis and changes of soil properties almost coincide with the order of age among the sand bars. However, the order of successional degree between Namusitdeung and Galmaegideung was more or less obscured because of cyclic succession driven by allogenic processes.

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Designing Pavement Marking for Hi-pass Lane Based on Kansei Engineering (이용자 감성분석을 통한 하이패스 차로 노면표시 설계 기법)

  • Hong, Sung-Min;Oh, Cheol;Jang, Ji-Yong;Kim, Gwang-Ho;Park, June-Young;Chang, Myung-Soon
    • International Journal of Highway Engineering
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    • v.14 no.1
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    • pp.73-83
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    • 2012
  • Effective use of traffic marking can lead to driver's safer driving by speed management and visibility enhancement. One of the critical factors in designing traffic marking is how to incorporate human factor issues into the design process. This study presented a methodology for evaluating the effectiveness of Hi-pass marking on Korean freeways based on kansei engineering. Hi-pass marking scenarios made by a virtual reality tool were used to evaluate the user's perceptions. Various combination of chevron angles and peripheral transverse(PT) bars were used for the evaluation. The results show that the most effective scenario is a combination of 60 degree chevron angle and an askew parallelogramshaped PT bar shaped. It is expected that the proposed method and outcome will be useful for making safer driving maneuvers.

A non-invasive sexing method reveals the patterns of sex-specific incubation behavior in Saunders's Gulls (Saundersilarus saundersi) (비침습적 성감별 방법에 의한 검은머리갈매기(Saundersilarus saundersi)의 암수 포란행동)

  • Joo, Eun-Jin;Ha, Mi-Ra;Jeong, Gilsang;Yoon, Jongmin
    • Korean Journal of Ornithology
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    • v.25 no.2
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    • pp.69-76
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    • 2018
  • Sexual dimorphism in birds refers to male-female differences in body size, plumage, color and/or behavior. In general, many seabirds, including the family of Laridae, are monomorphic in plumage-color, which makes the determination of sex difficult in the field because both parents also tend to share a great portion of parental care. The development of an inexpensive sexing tool facilitates understanding the degree of sex-specific parental care in the evolution of the life history. Here, we developed a non-invasive method for the determination of sex using the bill-head morphometric of known captive pairs and applied this tool to wild pairs to document factors underlying male-female parental care during the incubation period of Saunders's gulls (Saundersilarus saundersi). Males exhibited relatively larger bill-head ratios than their mates within naturally formed pairs in captivity, resulting in the determination of sex in12 wild pairs at the nest during the incubation period. Males and females equally shared the incubation role during the daytime, attending the nest at a high rate of 95%. However, the male's proportion of nest attentiveness greatly increased with time towards sunset, presumably reflecting the male duty for nighttime incubation. The present study provides a non-invasive method for the determination of sex in a monomorphic seagull species and highlights how male-female incubation behavior is associated with time of the day, rather than other ecological conditions.