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Changes of the Breeding State of Little Tern (Sterna albifrons) in the Nakdong Estuary, Busan, Republic of Korea (낙동강하구에서 쇠제비갈매기의 번식 상황의 변화)

  • Lee, In-Sup;Hong, Soon-Bok
    • Journal of Life Science
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    • v.19 no.11
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    • pp.1611-1616
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    • 2009
  • This study was conducted to determine the characteristics in breeding of the little tern Sterna albifrons in Shinja-do and Doyo-Deung in Nakdong estuary. The data was obtained in the middle and late 1990's and in the mid 2000's, which were analysed for the breeding information of the little tern. In Shinja-Do, a total of 638 nests were observed in 1995, and the average numbers of eggs laid per nest were 2.48. In 2004 and 2005, 94 and 456 nests were observed, and the average number of eggs laid per nest was 2.16 and 2.53, respectively. There was a significant difference between the average numbers of eggs laid per nest for the 3 respective years. In Doyo-Deung, a total of 269 nests were observed in 1998, and the average number of eggs laid per nest was 2.16. In 2004 and 2005, 1,023 and 1,123 nests were observed, and the average numbers of eggs laid per nest were 2.33 and 2.52, respectively. There was a significant difference (p<0.001) between the average number of eggs laid per nest as well. Hatching success rate by nesting site in Shinja-Do was calculated in 1995. Type A nest (nest located on dry sand land) showed a 56.8% success rate, and type B nest (nest located on the land with dwarf grass), type C nest (nest located on moist land) and type D nest (nest located on the land with shells) showed 55.3%, 36.6% and 59.3% success rates, respectively. The average hatching success rate in Shinja-Do was 54.5%. The most crucial factor for hatching failure was flood, especially, for the type C nests. The hatching success rate by the nesting site in Doyo-Deung showed an average of 73.2%. It was high in type D nest (83.8%) and type A nest (75.9%), and low in type C nest (59.7%). Again, the most crucial factor for hatching failure was flood, especially, for the type C nests. Nakdong estuary has been through many changes over time, particularly in recent. Therefore, continuous efforts to keep it a breeding place for the little tern are urgently required, including overall management of land, protection of reef and sand, etc.

Ecological Notes on Narcissus Flycatcher, Musciapa narcissina zanthopygia HAY - With special reference to the breeding process and feeding habits of nestlings during their nesting period- (흰눈섭황금새(Muscica narcissina zanthopygia HAY)의 생태-특히 번식경과와 육령기의 식습성)

  • WON, Pyong-Oh;RHEE, Kyung-Jho
    • The Korean Journal of Zoology
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    • v.8 no.2
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    • pp.89-127
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    • 1965
  • 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.

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Statistical Analysis of Clustered Interval-Censored Data with Informative Cluster Size (정보적군집 크기를 가진 군집화된 구간 중도절단자료 분석을 위한결합모형의 적용)

  • Kim, Yang-Jin;Yoo, Han-Na
    • Communications for Statistical Applications and Methods
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    • v.17 no.5
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    • pp.689-696
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    • 2010
  • Interval-censored data are commonly found in studies of diseases that progress without symptoms, which require clinical evaluation for detection. Several techniques have been suggested with independent assumption. However, the assumption will not be valid if observations come from clusters. Furthermore, when the cluster size relates to response variables, commonly used methods can bring biased results. For example, in a study on lymphatic filariasis, a parasitic disease where worms make several nests in the infected person's lymphatic vessels and reside until adulthood, the response variable of interest is the nest-extinction times. Since the extinction times of nests are checked by repeated ultrasound examinations, exact extinction times are not observed. Instead, data are composed of two examination points: the last examination time with living worms and the first examination time with dead worms. Furthermore, as Williamson et al. (2008) pointed out, larger nests show a tendency for low clearance rates. This association has been denoted as an informative cluster size. To analyze the relationship between the numbers of nests and interval-censored nest-extinction times, this study proposes a joint model for the relationship between cluster size and clustered interval-censored failure data.

Composition of the insect diet in feces of yellow-throated marten, Martes flavigula, in Jirisan National Park, South Korea

  • Choi, Moon Bo;Woo, Donggul;Choi, Tae Young
    • Journal of Ecology and Environment
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    • v.38 no.3
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    • pp.389-395
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    • 2015
  • The composition of the Martes flavigula diet has been extensively studied, but little is known about its insect component. This study characterized the insect diet and insect nest materials in the feces of M. flavigula. A total of 952 fecal samples were collected in Jirisan National Park from January 2009 to November 2011, and 1379 species or taxonomic groups were identified. M. flavigula fed on insects (8.7%) and bee wax (5.0%), which comprised 2.9% and 4.4% of the dry weight of M. flavigula feces, respectively. A total of 12 insect species belonging to 8 families in 3 orders were identified. The most frequently found insects were Hymenoptera (frequency of occurrence, FO, 89.1), including Vespa simillima simillima (FO, 37.3) and Vespula koreensis koreensis (FO, 20.0). The Vespidae constituted the majority of the insect diet in autumn when the diversity of marten's prey was strongly reduced, probably because the numbers of social insects were sufficient for M. flavigula. In addition, the data suggest that M. flavigula attacks the nests of social wasps in late autumn when males do not have a venomous sting and new queens are less aggressive than workers. Bee wax appeared in all seasons and the highest rate was from spring to early summer. However, the remains of honeybees were not found in feces; thus, M. flavigula presumably eats honey but not honeybees.

The Effects of the Breeding site of the Egrets and Herons by Road Construction, Palhyun-ri, Daegu, Korea (대구광역시 팔현리 지역 도로공사가 백로류 번식지에 미치는 영향)

  • Cha, Jae-Seok;Kim, Jae-Woong;Park, Hee-Cheon
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.152-158
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    • 2008
  • This survey was conducted to analyze the effect of road construction near the group breeding places of the egrets and herons located at Palhyun-ri, Daegu, on their breeding during four years from 2003 to 2006. With the number of the individuals of the whole egrets and herons have been decreased due to the three-year road construction work(2003-2005). When the road construction was temporally stopped in 2006, the number of individuals of egrets and herons except Cattle egret Bubulcus ibis increased and partocilarly, the Gray heron Ardea cinerea was found to have been influenced the most by this construction in comparison with other egrets and herons. The number od individuals of large egrets, little egrets and herons was found to decrease during the construction period. After cutting off the nest trees and removing some parts of the breeding site, the herons and egrets tended to move their nesting place from roadsides to the inside of the breeding area. Trees for the nests decreased due to the increase in fellen trees caused by bird nests per tree increased gradually. As for the formation ratio of trees for the nests, the ratio of pine trees lowered yearly while that of acacia and oak trees was increasing during the survey.

A Survey on the Family Ardeidae Habitat for the Selection of the Alternative Breeding Sites at the Urban Forest in Korea (도시숲 백로류의 잠재번식지 선정을 위한 서식환경 조사 - 군산 백로류 집단번식지를 중심으로 -)

  • Kim, Jung-so;Kim, Sang-Wook
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.20 no.2
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    • pp.1-12
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    • 2017
  • This study aims to provide the basic habitat data for the alternative breeding sites of Family Ardeidae including Ardea cinerea, Egretta alba modesta, Egretta intermedia, Egretta garzetta, Bubulcus ibis and Nycticorax nyciticorax. Species numbers, flight directions for detecting foraging grounds and current vegetation structure were investigated nesting at Gunsan urban forest area. Data were collected over a period of 10 weeks, from 15 June - 31 August 2014. The total nest and population of Family Ardeida were 684 and 1,712 respectively. Percentage of birds observed flying in 8 major compass directions were as follows. 57.27% of all birds were observed flying northwest, 22.09% were observed flying south and 13.40% were flying north. For possible foraging areas, to the northwest, there are Geumgang river tidal flats, and to the south, paddy fields and streams within 2km. Flying directions by species (${\chi}^2=287.18$, P<.001, Cramer's V=0.12) and by seasons(${\chi}^2=839.94$, P<.001, Cramer's V=0.19) showed significant difference statistically. In relation between species and directions, 60.31% and 24.05% of Bubulcus ibis and 59.40% and 23.00% of Ardea cinerea were observed flying northwest and south respectively. Vegetation in the sites consist of an overstory of 3 to 7 species. At site 1, Pinus thunbergii was the dominant species and site 2, Chamaecyparis obtusa. Understory vegetation is composed of shrubs, saplings and small trees of Chamaecyparis obtusa, Quercus acutissima, Smilax china and Platycarya strobilacea. Egrets and herons usually nested at the dense population and canopy overlayed forest, and especially branches and leaves of smallwood with less than 10cm of breast height diameter were relatively severely damaged due to the nesting and excreta.

Elderly response to alteration of existing house function in housing improvement area (주거지 재생지역의 기존주택 기능전환에 대한 노인의 반응연구)

  • Lim, Soo-Hyun;Lee, Yeun-Sook
    • KIEAE Journal
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    • v.10 no.2
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    • pp.9-18
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    • 2010
  • As an aging population has increased vastly and nuclear families have been a dominating family type in modern Korean society, the numbers of the elderly who suffer Empty Nest Syndrome and LID (Loss Isolation Depression) syndrome have been accelerated. These syndromes involve psychological instability, melancholy, and lethargy. To make the elderly get out of this phenomenon and live actively, the scheme of converting their existing house into shared housing was set as a hypothetical solution in this study. This study sets out to find out responses of the elderly to alter their own house's function in housing improvement area. A Small Workshop Panel method was used and the elderly aged 55 years upwards took part and they own a detached house in a housing improvement area that is relatively large for the elderly or the elderly couple to live alone. Through the workshop, problems that the elderly have been experiencing within their houses were looked into and responses of the elderly on altering their house to shared housing by introducing developed schematic plans. Although, the first response was negative, positive responses from the house owners were carried out when a visual support i.e. developed shared housing plan was provided. The positive response was based on the fact that subsidies from the government on house renovation and tenants matching programs are supported as shared housing could provide home owners economical support with rents and help them to feel less lonely. This is a way of relieving the elderly from being neglected and supporting them to live and age actively in their later lives. Furthermore, by providing a visual media to the elder residents in housing improvement area, their greater understandings on the development and addressing their opinions were possible. Therefore, more tools that promote elder residents' participation are needed for future housing improvement projects and an aging society.

Home owners' response on conversion of existing detached house to shared house (다가구 공동주택으로서의 전환에 대한 기존주택 소유자 반응 연구)

  • Lim, Soo-Hyun;Hwang, Geun-Young;Lee, Yea-Koo;Yang, Byoung-Ok;Lee, Yeun-Sook
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.11a
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    • pp.131-134
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    • 2008
  • The numbers of the elderly who suffer Empty Nest Syndrome have been accelerated as an aging population has increased vastly and nuclear families have been a dominating family type in modern Korean society. To make the elderly get out of this phenomenon and live actively, the scheme of converting their existing houses into shared houses was set as a hypothetical solution in this study, and finding out the responses of the elderly who owns their own houses is the purpose of the study. A small workshop panel method was used and the elderly aged 55 years upwards took part and they own a detached house that is relatively large for the elderly or the elderly couple to live alone. The workshop was consisted of 3 stages: 1. a survey 2. an interview 3. a site visit. Through this, problems that the elderly have been experiencing within their houses were looked into and the responses of the elderly on converting their houses to shared houses by introducing developed schematic plans. As a result, positive responses from the house owners were carried out based on the fact that subsidies from the government on house renovation and tenants matching programs are supported. Shared houses could provide home owners economical support with rents and help them to feel less lonely. This is one way of supporting the elderly to live and age actively in their later lives. Therefore, this idea should be established in connection with preparing aging, aged, and super-aged society.

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