• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.383-390
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• 2004

This study was conducted in three sites, Si-Hwa Lake, Dongman and Seoman island and Janguyeop island, from march, 1999 to september, 2002. The behaviors of pre-breeding season, territorial behaviors, reproductive ecology, foraging sites and behaviors, and the competition of reproduction and foods between intraspecific or interspecific of Eurasian Oystercatcher (Haematopus ostralegus) were observed in each studying sites. The breeding of Eurasian Oystercatcher started on the middle of April in Si-Hwa Lake and on the middle of May in Dongman and Seoman island and Janguyeop island. For intension of pair bond on pre-breeding season, Eurasian Oystercatcher foraged with pair and behaved male-female chasing flight behavior. The pair foraged with male and female before copulation. If other pairs and individuals approached in feeding site of pair, this pair attacked them with piping calling and intruder chasing flight. If continuos serial behaviors were not observed, the discrimination of male-female chasing flight and intruder chasing flight was difficult. Territorial behaviors classified four types; butterfly flight, calling behavior, chasing behavior, fight behavior. The important foraging sites in Si-Hwa Lake are the land place in Daeboo island, tidal flat of Bangameori, tidal flat a front of a stationary net for catching fishes and tidal flat a front of a view station for bird watching. Eurasian Oystercatcher foraged at tidal flat on low water of the tide and foraged at feeding sites near island on flood tide in Dongman and Seoman island. Eurasian Oystercater in Janguyeop island usually foraged feeding sites near island, because water level was not different between low water of the tide and flood tide. Eurasian Oystercatcher competed on foods of intraspecific and interspecific. They chased for taking foods by force in feeding sites and drove out intruders in feeding sites. The foods interspecific competition happened with Black-tailed Gull (Larus crassirostris). Eurasian Oystercatcher was robbed of foods and attacked by Black-tailed Gull. The individual of food competition with Black-tailed Gull was low foods intake rate comparison with other feeding sites and this individual flied out other feeding sites.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.207-216
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• 2005

Spawning behaviors of Squalidus gracilis majimae (Cyprinidae) were observed in the laboratory whose environmental factors such as light (D/L = 16 : 8), temperature ($20\;{\sim}\;24\;＾{\circ}C$), and dissolved oxygen (>8 mg $L^{-1}$) were quite regularly controlled. The behavioral patterns were categorized into three stages ofpre-spawning, spawning, and Post-spawning behaviors. In Particular, the pre-spawning stage was specified by 11 specific behavioral patterns of aggressive mating behaviors. During the spawning stage, the male and female performed four distinct spawning behaviors including sexual temptation, stimulation, egg spawning, and the separation, and randomly laid about 200 ${\sim}$ 300 eggs on the bottom substrates through the night. After finishing spawning, two adults separated toward their refuges and showed 3 types of post-spawning behaviors such as the resting, occasional eggs protecting, and the egg eating. The fish was identified as a partial-parental care species after the spawning.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.1-8
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• 2019

Pintail (Anas acuta) is the major wintering bird in South Korea and known as a major mediator of the highly pathogenic avian influenza (HPAI). Pintail migrates long distances between Russian Siberia and Korea. This species prefers a rice paddy area as their winter habitat. The purpose of this study is to provide the data necessary for the conservation and management of bird habitats in Korea by understanding the wintering home-range and habitat of pintail in Korea. We captured six pintails using a cannon-net in the winter of 2015 and attached the GPS-mobile phone based telemetry (WT-300) on them to study the wintering home-range and wintering habitat. We analyzed the tracking location data using ArcGIS 9.0 Animal Movement Extension and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range in the wintering ground analyzed by MCP was $677.3km^2$ (SD=130.2, n=6) while the maximum and minimum were $847.7km^2$ and $467.5km^2$, respectively. Extents of home-range analyzed by KDE were $194.7km^2$ (KDE 90%), $77.4km^2$ (KDE 70%), and $35.3km^2$ (KDE 50%). The pintails mostly used both sea and paddy field as habitat in the winter season and utilized paddy fields more during the nighttime and than the daytime. We concluded that the home-range and habitat of pintails in the winter could be used as the reference data for the preservation of species, management of habitats, and coping with a breakout of HPAI.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.350-356
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• 2016

The biggest factor in the success of breeding animals is selection of foods, which is determined by quality and quantity of habitats(Newton, 2003), in the case of This high biomass wetlands as an indicator of ecosystem function about Common Kestrel's choice of hunting area is expected to be an important clue of quality and quantity of habitats. For this study, it is divided into four types(Glasslands, Paddy fields, Dry fields, Rparian land) about Common Kestrel's hunting area in Yugu-eup, Gongju-si, Chungcheongnam-do, Recorded the behavior of Common Kestrel for three years during the breeding season from March to June(2014~2016). Result of investigation, hunting area showed a high hunting behavior in riversides and flight-hunting was frequently investigated from may to June. In addition flight-hunting's main food acquisition is mammal(the vole), while perching behavior's main food acquisition is insect according to the fact flight-hunting were mainly done in riversides, perching behavior were highly investigated than flight-hunting at glasslands and paddy fields and dry field. Hunting spot's coverage rate of plants covering the ground showed differences depending on hunting areas, but height of plants were not significant. Height of the plant according to hunting methods of flight-hunting to catch mammal(vole) was analyzed to prefer lower height than perching behavior Based on these results riversides are considered as a very important environmental factors for Common Kestrel's prey selection in breeding session.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.1
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• pp.39-51
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• 2011

Acute toxicity test and behavioral change analysis of seawater acclimated Japanese medaka were conducted to identify the brine effects on fish by seawater desalination. 7 day acute toxicity test of brine revealed linear concentration-response relationship from 40.0~80.0 psu treatment groups. There was no significant brine effect for 30-40 psu groups and mass mortality was observed from >50 psu exposure (7-day $LC_{50}$=51.4 psu). Images from the real time camera system were analyzed to observe the changes in behavioral patterns of medaka exposed to various salinity. 40.0 and 50.0 psu exposed groups were stabilized in behavioral patterns after 3.1 and 4.6 hours, respectively and 60.0 psu group showed sharp increase in activity during first 12 hours and 50% mortality thereafter. Similar patterns were observed to 70 and 80 psu groups and both experimental groups showed 100% mortality within 12 hours. Acute toxicity test and behavioral patterns showed very similar toxicity results which revealed the increases in mortality and behavioral activities from 50.0 psu. This critical salinity for fish impacts must be implemented to brine discharge strategy by seawater desalination into the coastal area. Also, we recommend that real time camera monitoring system must be a useful tool for early warning of fish toxicity for other applications. This research was funded by Ministry of Land, Transport and Maritime Affairs, Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.4
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• pp.337-346
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• 1992

Hydroacoustic surveys were conducted in the East China Sea, in the summers of 1990-1991 to investigate the distribution and migration behavior of fish, such as the diel changes in the distributions of fish, the thermoselection behavior of fish, and the fish reactions to a surveying vessel. The hydroacoustic observations were taken with a scientific echo sounder operating at 50kHz and a microcomputer-based echo processor. Fish samples were collected by bottom trawling and temperature was measured with a DBT system. The patterns of fish distributions were compared with the vertical profiles of water temperature. The results obtained can be summarized as follows: 1. The time series of hydroacoustic observations on the downward migration at dawn in the central region of East China Sea showed that the migration rate was 0.24 m/min. In this region, most of the fish collected by bottom trawling during the surveys were squid (Photologio edulis f. budo) and horse mackeral (Trachurus japonicus). 2. The hydroacoustic observations, which together associated with temperature data, indicated that squid and horse mackeral concentrated nocturally in a narrow vertical band of thermocline, particularly in summer when the survey region was strongly stratified. This result suggest that the nocturnal vertical distribution of these species evidently is controlled by temperature. 3. When the survey vessel, that is running at a speed of 11 knots, has suddenly stopped, the fish which concentrated beneath the transducer showed a strong avoidance reaction in the form of rapid downward migration. After a few minutes, the descending reaction disappeared and the fish slowly began the upward migration toward their original swimming positions. Trawl data suggest that the fish, which showed the avoidance reaction, was Liparis tessellatus.

• Korean small business review
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• v.42 no.1
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• pp.135-165
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• 2020

This study aimed to examine relationships between founders' entrepreneurial leadership, team learning behavior, team boundary spanning, and perceived performance in early-stage startups. The following results were recorded: (i) the indirect effects of entrepreneurial leadership on perceived performance via team learning behavior were statistically significant (β=.309, p<.05). (ii) relationships between team learning behavior and perceived performance were strengthened by team boundary spanning behavior (β=.259, p<.05). In this study, three practical implications are provided as follows: (i) startups need to seek team learning readiness and external learning stimulus to facilitate generative and transformative team learning; (ii) accelerators need to develop an entrepreneurial leadership program for founders; and (iii) startups need to explore external information by interacting with investors, R&D institutions, and other startups to strengthen the impact of team learning behavior on performance. Furthermore, two directions for future research are suggested as follows: (i) future researchers need to test causal relationships between entrepreneurial leadership and team learning behavior based on a newly designed time-series measurement plan; (ii) the actual effects of entrepreneurial leadership, team learning behavior and team boundary spanning on financial performance need to be tested two or three years later when the financial performance of early-stage startups usually becomes evident.

• 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.

• Journal of the Korean Geographical Society
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• v.33 no.spc
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• pp.697-707
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• 1998

인간과 환경과의 관계의 역사적 변천을 인구변화와 자원관리의 측면에서 분석하는 기존 관점은 인구기초이론, 기술기초이론, 시장기초이론 등으로 분류된다. 이러한 관점은 어느 한가지 변수를 독립 변수로 가정하는 입장을 취하므로 흔히 '단일요소이론'이라고 불리며, 제각기 장점이 있기는 하지만 현실 세계의 복합성을 단지 부분적으로 설명하는데 그치는 문제점을 내포하고 있다. 현실세계의 모든 사건은 개방된 체계 속에서 발생하기 때문에, 모든 사건은 단선적인 인과관계로 파악될 수 없을 만큼 서로 복합하게 얽혀 있다. 이에 대하여 문화생태이론은 단일요소이론의 그러한 한계를 극복하고 현실세계의 복합성을 분석할 수 있는 개념과 방법을 제시하고 있다. 문화생태이론은 실로 인간과 환경과의 관계가 역사적으로 변천해 온 과정을 탐구하는데 적합한 개념과 방법을 장점으로 내세우는 새로운 관점이라 할 수 있다. 문화생태이온은 인구, 기술, 시장, 제도 등 요소의 중요성이 시간과 장소에 따라 다를 수 있다는 가정 하에서 어떠한 요소라도 어느 한 장소와 시점에서 인간과 환경과의 관계의 변화를 주도할 수 있다고 기대한다. 한국 농촌의 인간과 환경과의 관계를 탐구함에 있어서 활성되어야 할 문화생태이론의 기초적인 개념은 '지역인간생태계'와 '문화적 적응'이다. 한국 농촌의 지역인간생태계는 그 특성상 인구, 농업, 시장, 제도로 구성되어 있다고 볼 수 있다. 문화적 적응이란 변화하는 환경 속에서 사회구성원들의 환경에 대한 적응도를 높일 수 있는 행동양식을 새로이 선택하는 행위를 일컫는다. 한국 농촌에서는 적응전략이란 농업의 집약화와 상업화 또는 산아제한과 인구이동이라는 측면에서 분석될 수 있을 것이다. 생존, 기술, 취락형태, 토지이용, 무역이나 교역 등은 적응전략을 분석하는데 간접적인 자료를 제공해 줄 것이다.

• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.595-605
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• 2017

This study was intended to investigate the effects of after-school forest healing programs on the pro-social behavior and self-efficacy of young children using the attributes of forest and the forest healing factors. The children attending a kindergarten located in ${\bigcirc}{\bigcirc}$ - dong, Cheongju city were divided into a test group which participated in the forest healing program activities and a control group which participated in the regular programs of the kindergarten but not in the forest healing program. Each group consisted of 20 boys and girls aged 3 to 5 years. The forest healing program was conducted once a week from 10 April to 10 July in 2017 for a total of 12 sessions, and each session lasted one hour (60 minutes). The pro-sociality behavior and self-efficacy test of the children was conducted before and after the forest healing program, and the data were analyzed using SPSS 18.0 program. The result showed that the pro-social behaviors that indicated the ability to execute the positive action and the self-efficacy that indicated the self-confidence were statistically significant (p<0.05). The young children who participated in the forest healing program improved their self-esteem through positive thoughts from being with their peer in nature. Moreover, they increased not only ecological knowledge but also consideration for others and cooperative spirit. They also greatly improved the ability to control personal emotion and the ability to form the personal relationship which are the sub-factors of pro-sociality, the ability to adapt to the early childhood education institution, and the physical efficacy which is the sub-factor of self-efficacy. It was concluded that the after-school forest healing program had a positive impact on pro-social behavior and self-efficacy.