Journal of the Yamashina Institute for Ornithology
Online ISSN : 1882-0999
Print ISSN : 1348-5032
Volume 44 , Issue 2
Showing 1-7 articles out of 7 articles from the selected issue
Special Contribution
Original Articles
  • Osamu K. Mikami, Masao Takahashi
    2013 Volume 44 Issue 2 Pages 67-78
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    With the decline in their natural habitat, grassland bird species have become of conservation concern. When a grassland is completely destroyed, the impact on birds can be relatively easily estimated. However, when a grassland is altered qualitatively, the impact cannot be estimated without detailed research, and few studies have investigated this aspect. Here, we report the qualitative change of vegetation between 1998 and 2010 of a wet-grassland, Hotoke-numa, located in Aomori Prefecture, northern Japan, and its impact on the five grassland avian species. During the 12-year interval, the mean height of the reed Phragmites australis decreased by 20 cm, whereas the height and degree of grasses in the lower layer increased. The latter might be a consequence of the increase of light penetration to the lower layer as a result of the decrease in the height of the reed. The numbers of individuals of Locustella pryeri, Emberiza schoeniclus and E. yessoensis increased by 36%, 171% and 94%, respectively, whereas Acrocephalus orientalis decreased by 39% and A. bistrigiceps decreased by 43%. According to previous published studies, the three species which increased preferred the vegetation present after the change, while the two species that decreased preferred the vegetation present before the change. The change in vegetation clearly influenced the number of individuals of the five species. Since the study area has many endangered species, it is urgently necessary to identify precisely which factors are responsible for the change in vegetation.
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  • Takeshi Shirai
    2013 Volume 44 Issue 2 Pages 79-91
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    Site fidelity to the colony and breeding histories of individual Grey Herons Ardea cinerea were examined by intensive and long-term (nine years) observations of 50 fledglings and 19 adult birds banded with colour-patterned rings in a single-species colony in suburban Tokyo. In total, 38 (76.0%) of 50 marked fledglings were never resighted in the natal colony. Of the 12 returning birds, four (33.3%) began to breed at 2-years-old, two (16.7%) at 3-years-old, one (8.3%) at 4-years-old, and five (41.7%) never bred. Two birds survived after 9 years from fledging. In total, 18 (94.7%) of 19 adult birds were resighted in the next breeding season and most of them (15/18) bred there. Birds tend to stay at the same breeding colony once they had returned. Some birds exhibited site fidelity to the breeding nest every year, but others did not. Pair bonds remained stable in four pairs throughout years until one individual in a pair was lost. The number of chicks fledged per nest did not change with the age of the parent. Two broods in the same breeding season were observed in 7 (9.0%) of 78 nests, in which at least one parent was marked. The maximum number of fledglings produced by a single male over the 9 years was 22. Of 23 birds that were resident for more than two years, four birds (all females) continued to stay at the colony site after the breeding season. However, 19 birds (eight males, three females, eight unsexed) left the colony after the late breeding season and were observed in outside locations, particularly at fixed feeding sites. The maximum distance of resighted, marked fledglings was 1,580 km southwest of the colony, 54 days after release.
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Reports
  • Michio Fukuda
    2013 Volume 44 Issue 2 Pages 93-96
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    Black-tailed Gulls Larus crassirostris have a black band on the upper tail. I measured the length from the tip of the tail to the outermost edge of the black band (white fringe on tail edge) of 22 captive individuals in the Ueno Zoological Gardens. The length of the white fringe increased in relation to the age of each individual. Therefore, it was suggested that the age of Black-tailed Gulls can be determined by the length of the white fringe until at least four or five years of age.
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  • Nariko Oka, Yuki Watanabe, Fumio Satoh
    2013 Volume 44 Issue 2 Pages 97-101
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    The causes of death of albatrosses are not well documented, owing to them breeding on remote uninhabited islands. During the chick-rearing season in late February 2004, two sub-adult Black-footed Albatrosses were found dead at Hatsunezaki colony, Torishima, Izu Islands. This locality holds the largest breeding population of this species in the western North Pacific. Leg bands indicated both birds to have been fledged at the same colony on the island in the early 2000s; one was 25 months old and another was 37 months old. The former was found to have a broken humerus and clavicle, and we therefore posit that it had died after crashing to the ground in the strong wind turbulence that had prevailed above the colony during the two days prior to discovery of the corpse. The latter individual was diagnosed with enteritis and ulcers throughout the small intestine, which probably resulted in its death.
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  • Keiko Nitta, Ikuko Hayakawa
    2013 Volume 44 Issue 2 Pages 102-106
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    We observed the behavior of eleven female Mandarin Ducks Aix galericulata during the incubation period. They left nests twice a day, in the early morning and evening. After that, they bathed, preened and foraged hurriedly in a short space of time. They were absent from the nest for a shorter time on the day before fledging and on the morning of fledging day than on other days during the incubation period.
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  • Yozo Tsukamoto, Miyako Tsurumi
    2013 Volume 44 Issue 2 Pages 107-112
    Published: March 30, 2013
    Released: March 30, 2015
    JOURNALS FREE ACCESS
    The Yamashina Institute of Ornithology owns the 11,982 photograph collection of Kenji Shimomura (1903–1967), the pioneer of wildlife photography in Japan. One of the prints in the collection (ID no.: AVSK_PM_1198, Fig.1a) depicts the stomach contents of Crested Ibis Nipponia nippon. When the computer database of the Shimomura collection was made, the photographer of this print was plausibly thought to be Shimomura, but was uncertain. Later we discovered in some publication that this photo was taken by Jicho Ishizawa (1899–1967), an insect and bird researcher at the then Wildlife Research Laboratory of the Ministry of Agriculture. Because the photo showing stomach contents of the endangered wild Crested Ibis is rarely publicized, we are of the opinion that the accurate identification of the photographer is academically important. Based on the memorandum on the backside of the print, handwriting analysis was made by Shimomura's and Ishizawa's relatives. The implications of the rubber stamps on the backside were also considered. These investigations concluded that the photo in question was almost certainly taken by Ishizawa, who also identified the stomach contents. We hope that this example will alert researchers to the possibility of incorrect citation of the photographer in earlier publications already published, and that, when detected, these be corrected in subsequent citations. Comments on related subjects that arose through the process of identifying the photographer are also given.
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