• 한국항공운항학회지
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• 제14권4호
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• pp.87-93
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• 2006

The black-tailed gull chicks, Larus crassirostris, recognize various adult voice signal base on the simple patterns. We investigated behavior change in black-tailed gull chicks through physical manipulation of mew call. They were playback in four situations differing in physical character: 1) frequency manipulation only, 2) duration manipulation only, 3) call intensity(dB) manipulation only, and 4) call interval manipulation only. We observed occurrence of different response of the chicks, which were categorized into two behaviors(hidden and return behavior). The manipulated frequency, duration, and intensity were directly correlated. The chicks exposed to only manipulated call interval(0.5, 1sec) made significantly more hidden and return behavior. Adult black-tailed gull only increased flight time on manipulated call interval. The results suggest that black-tailed gulls use short call interval for alarm signal. The analysis of alarm signal provides an important on basic study of bird strike.

• Animal cells and systems
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• 제1권4호
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• pp.565-569
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• 1997

Vocal repertoires of the B1ack-tailed gull (Larus crassirostris) were studied at established reproductive colonies. The Black-tailed gull has eleven different vocal signals which can be grouped into three different call classes according to behavioral functions: contact call, alarm call (attention call), and aggressive call. The contact call or mew call is the most frequently used and functions as means of recognition among individuals, particularly between parents and youngs. Our results show that each call plays .an important role in particular social relationships in a high- density breeding colony.

• 한국조류학회지
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• 제25권2호
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• pp.106-111
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• 2018

괭이갈매기는 동북아시아에서 가장 흔한 갈매기류 중 하나이며, IUCN에 의하면 LC(Least Concern)로 분류되어 있다. 인간의 활동이 해양환경에 영향을 미친 이래 괭이갈매기는 해양 환경오염과 서식지 교란의 중요한 지표종이 되었다. 본 연구에서 괭이갈매기가 6개의 미토콘드리아 CO1 하플로타입(haplotype)이 있고, 이중 일부 희귀 haplotype은 지리적으로 제한되어 나타난다는 사실을 확인하였으며, 이러한 현상은 본 종이 멀리 분산하지 않음을 암시한다. 본 논문은 한국에서 괭이갈매기를 대상으로 한 첫번째 개체군 유전적 연구결과이며, 환경지표종으로서 모니터링과 유전학적 연구의 기초자료가 될 것이다.

• Animal cells and systems
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• 제6권3호
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• pp.221-225
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• 2002

This study was conducted to find out how young black-tailed gulls (Larus crassirostris) recognize adult voice signals after hatching. For the experiment, adult voice recorded in the natural environment was played back at controlled intervals and intensity (dB) to 15 young gulls that were artificially hatched in the laboratory. The chirirah call frequency of young gulls increased as the intensity of the mew call increased. The chirirah response of the control group was highest to the mew call at intervals of 1.8s. The adult long ca11 and alarm call also showed similar results to the mew call when the interval and intensity were manipulated similar to the mew call. Based on the results of this experiment, it is assumed that the young black-tailed gulls recognize adult voice signals based on the simple structure of adult voice signals, that is, the interval and intensity of the voice.

• 한국임상수의학회지
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• 제31권4호
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• pp.354-356
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• 2014

Clinostomum (C.) complanatum is one of the trematode helminthes in birds and causes incidental infection in human. A black-tailed gull (Larus crassirostris) was referred to the Jeju wildlife rescue center. Because of the death of bird after two weeks treatment, necropsy was performed to the bird. Grossly, many living worms adhered to the oral mucosa including pharynx and esophagus were observed. The worms removed were identified as C. complanatum after morphological observation. The linguiform adult worms were $5.19{\pm}0.48mm$ long and $1.80{\pm}0.18mm$ wide. Histopathologically, severe necrosis and surrounding inflammation were observed at the infection sites of adult worm in pharynx and esophagus. This is the first report for C. complanatum infection in wild black-tailed gull in Korea.

• Ocean and Polar Research
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• 제28권2호
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• pp.201-207
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• 2006

We studied variation in clutch size, hatching, fledging and breeding success of the Black-tailed Gull (larus crassirostris) at Hongdo Island, which supported the largest breeding colony of the species, in South Korea in 1997 and 2000 to 2003. Cluck size was recorded in 1,388 nests and breeding success was estimated in 83 nests. Mean clutch size was 1.89 t 0.65. A total of 63.9% of the eggs hatched and 53.5% of the chicks survived until fledged. Breeding success was 34.2%. Causes of breeding failure were eggs missing (14.9%), rotten eggs (15.5%) and predation (2.4%) during the incubation period and chicks missing(35.8%), starvation (7.4%) and pecked chicks (3.2%) during the chick rearing period. In 2002, the main causes of breeding failure were eggs missing (17.2%) and rotten eggs (6.9%) during the incubation period and missing chicks (15.5%), starvation (3.5%) and pecked chicks (6.9%) during the chick rearing period. Most chick mortality occurred within three days after hatching.

• 한국환경과학회지
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• 제27권12호
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• pp.1279-1290
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• 2018

Sea gulls are high trophic level consumers in the coastal environment, and thus, which have been widely used to monitor contamination biomagnified through a food web. However, such monitoring studies using sea gulls have been rare in the Korean literature. The National Environmental Specimen Bank chose eggs of a black-tailed gulls (Larus crassirostris) to serve as an environmental specimen for the long-term monitoring of the coastal ecosystem affected by terrestrial pollutants. Black-tailed gull eggs were collected from Baengnyeongdo, Hongdo and Uleungdo, and their DDTs and total mercury content were determined. The highest concentration of ${\Sigma}DDTs$ was $231.6{\pm}106.1{\mu}g/kg$ wet in Baengnyeongdo, followed by $230.0{\pm}123.8{\mu}g/kg$ wet in Ulleungdo, and $117.7{\pm}18.3{\mu}g/kg$ wet in Hongdo. In addition, total mercury was detected at $414.5{\pm}97.6{\mu}g/kg$ wet in Ulleungdo, $363.9{\pm}123.6{\mu}g/kg$ wet in Hongdo, and $237.5{\pm}42.3{\mu}g/kg$ wet in Baengnyeongdo. Relatively high concentrations of the target pollutants were recorded in specimens from Ulleungdo. Additional comprehensive and prolonged studies are required to elucidate spatial and temporal patterns of contamination in black-tailed gull eggs with regard to monitoring contaminant trends in eggs and prey.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.69-73
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• 2008

We studied the functional roles of two types of calls, mew calls and mobbing calls, of the black-tailed gull (Larus crassirostris) by examining responses of mixed flocks of gulls to the playback calls. Playback experiments were conducted on four days between 11 May and 5 June 2007 at 16 sites in Sinjindo-ri and Dowhang-ri, Taean-gun, Chungnam province and Imjado, Sinan-gun, Jeonnam province, South Korea. We examined the anti-predator responses of the gulls to the playback trials. We found that gull flocks initially responded to mew call playbacks by mobbing in less than half of playback trials (6/14) while all trials involving playbacks of the mobbing call and control (group mobbing) call evoked mobbing. When trials in which no response was recorded were excluded, we found that the gulls' responses to mobbing and group mobbing call playbacks was more intense than their response to mew call playbacks, in that gulls mobbed longer, more gulls responded, and gulls took flight after a shorter time interval. However, the intensity of the gulls' response did not differ in mobbing call and group mobbing call playbacks. The results of this study suggest that the mixed-species flocks of gulls discriminate between the mew calls and the mobbing calls.

• Ocean and Polar Research
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• 제41권2호
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• pp.99-105
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• 2019

Black-tailed gulls, Larus crassirostris, have been known as resident birds in Korea, but their wintering and breeding habitat ranges were little known about. We investigated the habitat ranges of Blacktailed gulls breeding on Dokdo Island - which is the eastern end of their breeding colonies in Korea. Three adult Black-tailed gulls were fitted with Global Positioning System data loggers in May 2018 and their positions were tracked for 9 days, 245 days and 365 days each respectively. Black-tailed gulls stayed on Dokdo Island until June for breeding purposes and moved down to the southern part of Japan for wintering. The following year, a Black-tailed gull started to move northward in February and returned to Dokdo Island in April. They traveled a total of $207,334-229,507km^2$ (MCP) throughout a whole year. Based on location density categories accounting for 50% of locations, they used 3,618 to $3,803km^2$ in area. Black-tailed gulls breeding on Dokdo Island used smaller habitat ranges during the wintering period than the other periods. This is the first report on the habitat ranges of Black-tailed gulls breeding on Dokdo Island.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.157.1-157
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• 1998

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