• Title/Summary/Keyword: steller's sea eagle

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Moult Patterns of Tail Feathers of Immature Steller's Sea Eagle(Haliaeetus pelagicus)raised in Captivity (사육상태에서 참수리(Haliaeetus pelagicus) 미성조 꼬리깃의 깃갈이 방식)

  • Kang, Seung-Gu;Lee, In-Sup
    • Korean Journal of Environment and Ecology
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    • v.22 no.4
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    • pp.435-441
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    • 2008
  • This study conducted a survey on the moulting sequence subsequent to age of Haliaeetus pelagicus raised in captivity at the Ornithology Laboratory attached to Kyungsung University for about six years from November, 2000 until July, 2006. The survey indicated that the moult of rectrices usually began in July and continued until April of the next year and most of the rectrices were replaced by one-time moult. Usually, about two thirds of the tail feathers were replaced while the rest were replaced no later than April of the next year, and the moult also continued during the wintertime. The total number of rectrices was 14, and the moult progressed alternately on a systematic basis. The progress of the moult for female & male was made on four stages and three stages respectively and the characteristic shown on every stage of the moult was that the left & right tail feathers progressed symmetrically and not until one stage of progress almost completed did the next stage began. The color of the juvenile steller's sea-eagle was dotted with black spots on its original white color and there existed regular black belt on its feather's fringes; however, it was difficult to identify its age by tail feathers only because there was almost no difference in color between feathers ranging from the first to the third generation(1st-3rd summer feathers). In addition, this research took the different amounts of black-speckled pattern appearing by individual into consideration. There existed slight black speckles in white color feathers of the fourth generation(the 4th summer feathers) while showing a big difference compared to the 3rd generation feathers. The 5th generation feathers[the 5th summer feathers]were found to be equipped with perfect tail feathers having virgin white of a steller's sea-eagle after completing its 4th molt. When observing a steller's sea-eagle in the open air, it is necessary for an observer to have a deliberate examination in judging its age belonging to the 1st-3rd generation feathers, and it is considered that the changes of other parts of feathers should be also observed besides tail feathers.

Molting Patterns of Flight Feathers of Immature Steller's Sea Eagle(Haliaeetus pelagicus) Raised in Captivity (사육상태에서 자란 참수리(Haliaeetus pelagicus) 미성조 날개깃의 깃갈이 방식)

  • Kang, Seung-Gu;Lee, In-Sup
    • Journal of Life Science
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    • v.19 no.1
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    • pp.58-64
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    • 2009
  • This study was conducted to know the molting sequence and the aging points of flight feathers of steller's sea eagles (Haliaeetus pelagicus). For this study, two captive immature steller's sea eagles raised at the Ornithology Laboratory attached to Kyungsung University were surveyed for five years from Nov. 2000 to Nov. 2005. The survey indicated that the first molting began in July of the second year, and the primaries of P1-3, the secondaries of S18-19 (female), S17-18 (male), and S1 and S4 were replaced by one-time with second generation feathers. Generally molting stopped during the winter period, but a few feathers continued to molt during the winter. The two secondaries of S18-19 (female) and S17-18 (male) always molted every year but some of the juvenile secondaries (male: S10, S11, etc) retained for 2 or 3 years. In the molting order of primaries, the first molting started at P1 and it proceeded to P10 of outside. In the secondaries, the first molting started at S17(male) and S19(female), and it proceeded to outside. After that molting it started at S1 and proceeded to inside. In the other secondaries, the pattern of molting which proceeded in the mid-part of the secondaries was usually beginning in several different points at the same time. The molting seemed as if it depends on both the conditions of the individuals and the environment, so it was very difficult to explain the molting pattern in the mid-part of the secondaries. The longer quills (P7, P8) required for more than 68 days to develop. In the comparison of the length in the remiges between the first and the second generation feathers, the first generation feathers were the larger than that of the second. And the reduction of the length between the second and the third generation feathers was a few. The reduction of the length between the third and the fourth generation feathers was slight. The juvenile primaries were dark brown with a whitish base, which could be observed until the second or the third generation feathers (in their third or fourth winter plumage).

Distribution Status of Natural Monument Birds in Nakdong River Estuary (낙동강하구에 서식하는 천연기념물 조류의 분포 현황)

  • Yu, Jae Pyoung;Kang, Jung Hoon;Jin, Seon Deok;Paik, In Hwan;Hahm, Kyu Hwang;Paek, Woon Kee
    • Korean Journal of Heritage: History & Science
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    • v.43 no.1
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    • pp.86-99
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    • 2010
  • Among Natural monument birds, a total of 11 species and 2,209 individuals were found in Nakdong river estuary from March 2007 to February 2008 including Eurasian Oystereacher (Haematopus ostralegus; No. 326), Mandarin Duck (Aix galericulata; No.327), Tundra Swan (Cygnus columbianus; No.201-1), Whooper Swan (Cygnus cygnus; No.201-2), Black-faced Spoonbilll (Platalea minor; No.205-1), Eurasian Spoonbill (Platalea leucorodia ; No.205-2), Steller's Sea Eagle (Haliaeetus pelagicus; No.243-3), White-tailed Sea Eagle (Haliaeetus albicilla ; No.243-4), Hen Harrier (Circus cyaneus; No.323-6), Common Kestrel (Falco tinnunculus; No.323-8) and Swan Goose (Anser cygnoides; No.325-1). Among the habitats for migratory birds in Korea, the Nakdong river estuary is the only place where more than 2,000 individuals of Whooper Swan(Cygnus cygnus) spend winter. Eulsukdo, Myeongji Flat and neighboring tidal flats (Myeonggeummeori, Baikhapdeung, Doyodeung, Jangjado, etc.) are major habitats for natural monument birds such as Eurasian Spoonbill(Platalea leucorodia ), Whooper Swan(Cygnus cygnus) and Swan Goose(Anser cygnoides). A colony of aquatic plants such as Common Bulrush(Scirpus triqueter) and Common Reed(Phragmites communis) serves as a feeding and resting place for birds in the Anatidae family including ducks, swans and geese. Plans for management and conservation of the habitats and the natural monument birds in Nakdong river estuary are as follows: minimization of water contamination, construction and management of aquatic plants habitats, protection of sandbanks, security of stable habitats, and consistent monitoring.