A Report of Brood Parasitism by the Cattle Egret (Bubulcus ibis) in Korea

Yu-Seong Choi,Jin-Young Park,Hyung-Kyu Nam,Young-Min Moon,Kwan-Mok Kim,Gilsang Jeong 한국조류학회II 2013 한국조류학회지 Vol.20 No.2

On June 16, 2013, a nest containing three Intermediate Egret (Egretta intermedia) chicks and one Cattle Egret (Bubulcus ibis) chick was found at a mixed-species heronry (N36°52"15", E127°02"10") in Asan, Chungcheongnam-do, Korea. Based on body size and the development of the primary wing feathers, the three intermediate egret chicks were estimated to be more than 15 days old, and the Cattle Egret chick between 10 and 12 days old. The tree containing the nest was located on the edge of the colony, and contained only this nest. There were no other Cattle Egret nests in the immediate vicinity. This fact precludes the possibility that the Cattle Egret egg dropped from another nest, or that a Cattle Egret chick walked from a neighboring nest. In addition, the Cattle Egret chick had successfully eaten prey with the Intermediate Egret chicks. This means that the Intermediate Egret parents fed the Cattle Egret chick without rejecting it. Based on these observations, we suggest that this is a case of brood parasitism of an Intermediate Egret nest by a Cattle Egret. This is the first report of brood parasitism in a Korean egret population.

번식기동안 백로과 조류의 종별 취식지 이용

이윤경,김동원,장병순,유승화,김창회,강종현,권인기,류지은,서재화,서민환,박진영 한국조류학회II 2012 한국조류학회지 Vol.19 No.2

본 연구는 우리나라에서 집단으로 번식하는 백로과 조류 중 5종(왜가리 Ardea cinerea, 중대백로 A. alba, 쇠백로 Egretta garzetta, 황로 Bubulcus ibis, 중백로 E. intermedia)의 중요한 취식지 유형을 알아보고, 종별 시기에 따른 취식지 이용의 변화를 파악하기 위해 수행되었다. 2011년 번식기(4월-7월)에 관찰한 백로과 조류는 총 5,806개체(왜가리 1,797개체, 중대백로 1,504개체, 쇠백로 680개체, 황로 1,281개체, 중백로 544개체)였으며, 가장 많은 개체수가 이용하는 취식지는 논(59%)으로 나타났고, 다음으로 하천, 갯벌, 저수지 등을 많이 이용하였다. 종별로 선호하는 취식지를 살펴보면, 왜가리는 하천(41%), 중대백로와 쇠백로는 논(53%, 58%)과 하천(33%, 28%), 황로와 중백로는 논(89%, 98%)을 주로 이용하였다. 다양한 서식지를 이용하는 왜가리, 중대백로, 쇠백로는 시기에 따라 논, 하천, 갯벌, 저수지 등의 이용 비율이 다르게 나타났고, 중백로는 시기와 상관없이 번식기간 내내 논을 주로 이용하였다. 본 조사결과에서 논과 하천은 번식기의 백로과 조류에게 중요한 취식지역이었다. 그러나 인간의 활동영역과 겹치는 이들 서식지는 환경이 급격하게 변화하고 있으며, 이러한 변화가 백로과 조류의 번식에 어떤 영향을 끼치는지에 대한 조사가 이루어져야 할 것으로 판단된다. We investigated feeding habitats and seasonal uses of 5 species of colonial herons (Grey Herons Ardea cinerea, Great Egrets A. alba, Little Egrets Egretta garzetta, Cattle Egrets Bubulcus ibis, Intermediate Egrets E. intermedia) during the breeding season. A total of 5,806 individuals was inspected: 1,797 in Grey Herons, 1,504 in Great Egrets, 680 in Little Egrets, 1,281 in Cattle Egrets, and 544 in Intermediate Egrets. These herons foraged for food at rice fields (59%), rivers (26%), tidal flats (8%) or reservoirs (7%). The feeding habitat preference was different among species: rivers for Grey Herons, both rice fields and rivers for Great Egrets and Little Egrets, rice fields for Cattle Egrets and Intermediate Egrets. Grey Herons, Great Egrets, and Little Egrets used various habitats for feeding although the degree of the use of habitats was different according to seasons. On the other hand, Intermediate Egrets consistently used at rice fields for feeding regardless of seasons. Our study showed that the most significant feeding habitat of herons was rice fields and followed by rivers during the breeding season. However, these habitats which overlap with living space for humans have dramatically changed due to pressures for economic development in recent years. We need further long-term studies on the change of breeding populations of colonial herons to the environmental changes of important feeding habitats.

Feeding efficiency of Great Egrets (Ardea alba modesta) in two different habitats, rice fields and a reservoir, during the breeding season

Yu-Seong Choi,Sun-Sook Kim,Jeong-Chil Yoo 한국조류학회II 2014 한국조류학회지 Vol.21 No.1

The foraging efficiency of Great Egrets (Ardea alba modesta) in two different habitats (rice fields and reservoir habitats in Asan City, Chungcheongnam-do, Korea) was compared during the breeding seasons (May to June) of 2006 and 2007. The feeding activities of Great Egrets in both rice fields and reservoir habitats showed similar seasonal patterns. Pecking and capture rates were higher in June than in May, but the prey items captured were larger in May than in June. The feeding activities of Great Egrets also showed significant variation among microhabitat types within a reservoir. For instance, pecking and capture rates were higher in areas with submerged plants, but the capture success rate did not vary according to microhabitat type. In the rice field habitats, Great Egrets had higher pecking rates in the planting stage than in earlier stages (i.e., flooding and plowing stages), and they also walked more to find prey. These results indicate that the feeding efficiency of Great Egrets varies according to the structure and condition of their feeding habitats. However, the feeding activities of Great Egrets were similar between rice fields and reservoir habitats. Therefore, the results of this study suggest that during the breeding season, both rice fields and reservoirs may provide important feeding habitats for Great Egrets.

Feeding activity of cattle egrets and intermediate egrets at different stages of rice culture in Korea

최유성,김선숙,유정칠 한국생태학회 2010 Journal of Ecology and Environment Vol.33 No.2

This study was conducted to investigate the feeding efficiency of the cattle egret (Bubulcus ibis) and the intermediate egret (Ardea intermedia) in relation to the stage of rice culture during two breeding seasons, 2006 and 2007, in Asan city,Chungcheongnam-do, South Korea. Cattle egrets caught mainly small invertebrate prey (insects and spiders, 98.4%)during all stages of rice cultivation, and had a higher prey capture rate in the plowing stage (14.98 prey/min) than in other stages (2.82-3.51 prey/min). Therefore, the biomass intake rate of cattle egrets was highest in the plowing stage. The intermediate egret captured both loaches (43.4%) and small invertebrates (50.6%). The prey capture rates of intermediate egrets increased gradually from the flooding stage (0.38 prey/min) to the planting stage (1.09 prey/min), and decreased in the growing stage (1.04 prey/min). However, intermediate egrets had the highest biomass intake rates in the plowing stage because more loaches were caught in the plowing stage (0.54 loaches/min) than other stages (0.23-0.36loaches/min). Consequently, both intermediate egrets and cattle egrets had high energy intakes in the plowing stage and rice fields provided an important feeding habitat for both species.

Feeding activity of cattle egrets and intermediate egrets at different stages of rice culture in Korea

Choi, Yu-Seong,Kim, Sun-Sook,Yoo, Jeong-Chil The Ecological Society of Korea 2010 Journal of Ecology and Environment Vol.33 No.2

This study was conducted to investigate the feeding efficiency of the cattle egret (Bubulcus ibis) and the intermediate egret (Ardea intermedia) in relation to the stage of rice culture during two breeding seasons, 2006 and 2007, in Asan city, Chungcheongnam-do, South Korea. Cattle egrets caught mainly small invertebrate prey (insects and spiders, 98.4%) during all stages of rice cultivation, and had a higher prey capture rate in the plowing stage (14.98 prey/min) than in other stages (2.82-3.51 prey/min). Therefore, the biomass intake rate of cattle egrets was highest in the plowing stage. The intermediate egret captured both loaches (43.4%) and small invertebrates (50.6%). The prey capture rates of intermediate egrets increased gradually from the flooding stage (0.38 prey/min) to the planting stage (1.09 prey/min), and decreased in the growing stage (1.04 prey/min). However, intermediate egrets had the highest biomass intake rates in the plowing stage because more loaches were caught in the plowing stage (0.54 loaches/min) than other stages (0.23-0.36 loaches/min). Consequently, both intermediate egrets and cattle egrets had high energy intakes in the plowing stage and rice fields provided an important feeding habitat for both species.

Foraging Habitat Preferences of Herons and Egrets

Choi, Yu-Seong,Kwon, In-Ki,Yoo, Jeong-Chil The Ecological Society of Korea 2007 Journal of Ecology and Environment Vol.30 No.3

We investigated the foraging habitat preferences of herons and egrets in an agricultural area in Asan city, Chungcheongnam-do, Korea. In the study area, rice fields were the most abundant habitat type (86.8%) and total suitable feeding habitat was greater in the northern area (59.0%) than the southern area (22.5%) of the colony. Most feeding herons and egrets were located in the northern area of the colony. The number of feeding individuals in a given area was related to the available feeding area (Pearson correlation, r=0.773, p<0.001 for field habitats; r=0.901, p<0.001 for freshwater habitats). Feeding habitat preferences differed among species. Grey herons (Ardea cinerea), great egrets (Egretta alba), and black-crowned night herons (Nycticorax nycticorax) used reservoirs and ditches. However, intermediate egrets (E. intermedia) and cattle egrets (Bubulcus ibis) were dependent on rice fields. The little egret (E. garzetta) was a habitat generalist using all types of habitats. The two largest species, grey herons and great egrets, fed at deeper site than little egrets and foraged in deeper sites in reservoirs than in ditches (${\chi}^2-test,\;{\chi}^2{_3}=26.6$ and p<0.001 for grey herons, ${\chi}^2{_3}=17.5$ and p<0.001 for great egrets). All species displayed seasonal changes in feeding habitat use and these changes were related with changes in availability of feeding habitats.

朝鮮時代 白鷺圖, 그 表象의 변천

고연희 고려대학교 민족문화연구원 한국문학연구소 2003 民族文化硏究 Vol.38 No.-

白鷺는 물가에 내려앉아 물고기를 잡아 먹는 새로, 그 모습이 희고 크며 머리에 흰 장식털이 솟아나 깨끗하고 고결한 이미지로 인식되는 새이다. 백로를 그린 백로도는 고려시대부터 감상화로 그려지기 시작하여 조선시대에 지속적으로 그려졌다. 백로도는 매, 학, 기러기 다음으로 많이 그려진 새그림이며, 대개는 기러기 혹은 학그림과 함께 畵帖이나 屛風으로 그려졌다. 조선시대 백로도는 크게 세 가지의 유형으로 전개되었으며, 화면상의 유형전개에 따라 그림의 뜻이나 기능도 달리 전개되었던 것으로 보인다. 첫 단계는 조선조에서 17세기 부렵까지 정착된 雙笠型 백로도이다. 두 마리의 백로가 가을 연못가 시든 연잎 앞에 서 있는 古典的 화면으로, 섬세한 수묵법으로 표현되었다. 문인들은 이 그림을 보면서 속세에서 벗어난 한적한 정취 혹은 물고기를 잡느라 물가에 서 있는 백로에 대한 자연이해로 흥겨운 감상을 펼쳐냈다. 그 다음으로 17세기 중반기무렵부터 ‘立型’ 백로도가 나타났다. 시든 연과 연밥의 배경이 점차 사라지고 갈대만 있는 쓸쓸한 배경에 한 마리 백로가 서있는 장면이다. 이 유형의 백로도는 거친 필묵법의 소략한 표현으로 자연의 백로보다는 필묵의 멋을 살려낸 그림이다. 또한 그려진 한 마리의 백로는 지극히 정신적인 존재로 보인다. 조선후기에 인기를 누렸던 그림이다. 19세기 이래로 근대로 들기까지 새로 등장한 민화류 그림에서는 쌍립형 백로도도 많이 그려졌지만, 한 마리가 날아오고 한 마리를 서서 보는 一飛一笠型의 새로운 백로도가 또한 큰 병풍도에 잘 그려졌다. 민화류 백로도들은 연꽃을 크고 밝게 백로는 하얗게 채색하여 한적하거나 정신적인 느낌은 사라지고 풍요롭고 화려한 분위기가 넘친다. 대개 화목하기를 바라는 민화적 소망을 담아낸 것으로 보인다. 이 세 단계의 백로도 유형은 중국의 백로도 화풍과 관련을 보여주지만, 문인들의 감상을 누리며 쌍립형이 지속된 점이나 소박한 바람을 담아 간결한 구도의 일비일립형이 유행한 점은 한국 백로도의 특징적 면모들이다. Thank to the all-white and tall appearance, snowy egret has been regarded as a bird of lofty character and choosen as a good object of paintings in East Asia. Egret was painted continuely through Koryo and Choson periods in Korea, too. Most of the painting of Egret was worked in the form of an album or a fooding screen with paintings of wild goose and crane. There seem to be three types in the egret painting of Korea. The first type is the type of ‘two standing’ by the pond of lotus all wilted in late autumn. It was painted with delicate skill of bruch and ink, having a charm of desolate seene. The literati enjoyed the flavour of the scene, the mood of renouncing the world, and the nature of the egret that looks like standing aloft, but setting its eyes on a fish in the other sense. The second type is ‘one standing’. The only one egret is standing in a field of reeds. It was painted with simple bruch work, evoking spiritual mood. The other type is ‘one flying and one standing’. It belongs to folk painting (Minhua) of which function is to express folk’s wishes. The paintings of third type was worked not in ink-washing but in colour like the most of folk painting. As they accedtuate the colour of snowy egret and flowers of lotus, the egrets in the paintings of the third type look like wonderful lovers. So the meaning of the third type seem to be the desire of living in harmony. Although it’s true that the three types show some influence from Chinese paintings, there are features in Korean painting of egret in that the two standing type continued long under the literati’s taste and the one flying one standing type was in vogue in popular simple desire.

A Study of Feeding Methods in Five Species of Herons and Egrets in Korea

최유성,권인기,유정칠 한국생태학회 2008 Journal of Ecology and Environment Vol.31 No.2

Feding methods of five species of herons and egrets were studied in an agricultural landscapein Asan city, Chungcheongnam-do, Korea in 2006. Grey herons primarily hunted while standing, whereas great egrets fed while walking slowly. Two smaller species, little and cattle egrets, were active foragers, feeding both while walking quickly and walking slowly. Little egrets were the only species using the foot stirring method. The medium-sized heron, intermediate egrets, foraged mainly while walking slowly or leaning. For grey herons, great egrets and little egrets, the frequency of use of different feeding methods was different between habitats: these species used the leaning method more frequently in rice fields than in reservoirs and ditches. Also, most herons (all species other than great egrets) showed seasonal changes in their feeding methods that are related to changes in habitat condition.

A Study of Feeding Methods in Five Species of Herons and Egrets in Korea

Choi, Yu-Seong,Kwon, In-Ki,Yoo, Jeong-Chil The Ecological Society of Korea 2008 Journal of Ecology and Environment Vol.31 No.2

Feeding methods of five species of herons and egrets were studied in an agricultural landscape in Asan city, Chungcheongnam-do, Korea in 2006. Grey herons primarily hunted while standing, whereas great egrets fed while walking slowly. Two smaller species, little and cattle egrets, were active foragers, feeding both while walking quickly and walking slowly. Little egrets were the only species using the foot stirring method. The medium-sized heron, intermediate egrets, foraged mainly while walking slowly or leaning. For grey herons, great egrets and little egrets, the frequency of use of different feeding methods was different between habitats: these species used the leaning method more frequently in rice fields than in reservoirs and ditches. Also, most herons (all species other than great egrets) showed seasonal changes in their feeding methods that are related to changes in habitat condition.

낙동강하구에서 백로류(Egretta spp.)의 장기적 도래 현황

홍순복(Soon-Bok Hong),이인섭(In-Sup Lee) 한국조류학회II 2010 한국조류학회지 Vol.17 No.3

본 연구는 1990년 전반기(1989년 5월 ~ 1993년 4월)의 자료와 2000년 중반기(2002년 5월 ~ 2006년 4월)의 자료를 분석하여 주변 환경이 급변하는 낙동강 하구에서 백로류(Egretta spp.)의 장기적 도래 현황을 파악하기 위하여 이루어졌다. 조사기간(1989년 5월 ~ 1993년4월, 2002년 5월 ~ 2003년 4월, 총 8개년도)에 관찰된 백로류(Egretta spp.)는 총 5종 6,686개체이었다. 1990년 전반기(1989년 ~ 1993년)와 2000년 중반기(2002년 ~ 2006년)까지 조사한 백로류(Egretta spp.)들의 월평균 값은 1990년 전반기에는 8월부터 점진적으로 개체수가 증가되어 9월에 가장 많은 개체수가 관찰되었으며, 2000년 중반기에는 7월부터 점진적으로 개체수가 증가되어 8월에 가장 많은 개체수가 관찰되었다. 또한 월별 개체수의 평균에 있어서는 1990년대보다 2000년대에서 약 3 ~ 4배 이상 많이 관찰되었다. 우점종은 1990년대 전반기와 2000년대 중반기 모두 중대백로, 쇠백로, 중백로 순으로 나타났다. 1990년 전반기 조사 결과와 2000년 중반기 조사 결과를 T-검증한 결과, 3월부터 8월까지와 10월의 것은 5% 수준에서 유의한 것으로 나타나 3월부터 8월까지와 10월의 개체수 사이에는 의미 있는 차이가 있는 것으로 나타났다. 또한 2000년대에 조사한 자료를 지역별로 구분하여 종과 개체수의 유사도를 보면, 매년 유사도가 달라지고 있어 이 지역에서 백로류의 서식환경이 빠르게 변화하고 있음을 알 수 있었다. 백로류의 경우 봄 보다는 가을에 상단부인 대마등과 을숙도를 채식지와 휴식지로 이용하는 개체가 많았고, 도래시기에 있어서 2000년대 중반기에서 1990년대 전반기 보다 빨라진 것은, 이전(1990년대)에는 남하하는 도중 잠깐 쉬어가는 기착지역할을 하였으나, 현재(2000년 중반)에는 주변에 백로류의 휴식 및 잠자리로 이용할 수 있는 지역(대마등과 인공섬의 아카시아 군락 등)이 생겼기 때문에 이전 보다 일찍 도래하여 서식하다가 월동지로 남하하는 것으로 판단된다. To know the visitation aspect of Egrets in the long period at Nakdong estuary, Busan, Korea, we compared the data collected during the two periods between May 1989 and April 1993, and between May 2002 and April 2006.Over for the 8 years of field surveys, 6,686 individuals of egrets from 5 species were observed in the Nakdong estuary.In the early 1990s, the average number of species gradually increased from August and the most number of individuals were observed in September. In the middle 2000s, gradually increased and the most number of individuals were observed in August. The average number of individuals recorded in the middle 2000s was 2-3 times higher than that recorded in the early 1990s. Dominant species was ordered Egretta alba modesta, Egretta alba garzetta and Egretta intermedia both in 1990s and in 2000s. Statistical analysis using a t-test indicated that the number of individuals showed significant difference at 5% level between from March to August and October in the early 1990s and the middle 2000s. The similarity of the site was annually changed in the middle 2000s, and this result showed that habitat environment of egrets in the Nakdong estuary was speedy changed annually. More number of egrets seemed to choose Daema-deung and Eulsuk-Do located at upper site of Nakdong estuary as feeding site and resting site especially in autumn than in spring. More number of egrets arrived early at Nakdong estuary in the middle 2000s than in the early 1990s, it was thought that more feeding sites and resting sites were provided for the birds in 2000s than in 1990s at this place.