ORNITHOLOGICAL SCIENCE
Print ISSN : 1347-0558
最新号
選択された号の論文の13件中1~13を表示しています
EDITORIAL
ORIGINAL ARTICLE
  • Giorgia CASPANI, Tomoko G. FUJII, Tomoko MIZUHARA, R. Tucker GILMAN, K ...
    原稿種別: ORIGINAL ARTICLE
    2020 年 19 巻 1 号 p. 3-14
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル 認証あり

    Peak shift in mate preference learning can be a driver of rapid repeated speciation. Therefore, clades that have undergone recent adaptive radiations are predicted to show biased learning of signals from the opposite sex. The estrildid finches are one such clade. In species including the Zebra Finch Taeniopygia guttata and the Bengalese Finch Lonchura striata var. domestica, females choose mates in part based on their songs. Consistent with theory, female Zebra Finches show peak shift in their learned response to male song characteristics. We used operant conditioning to train female Bengalese Finches to respond to songs with trills of one length and to ignore songs with trills of another length. Then, we exposed those females to songs with a range of trill lengths, and we observed their responses. We found that at least some Bengalese Finches also show behaviour consistent with peak shift in their response to male songs. Moreover, females evaluated songs relative to other songs they had recently heard. Our results suggest that females respond to male sexual signals with bias in multiple species in the rapidly speciating estrildid clade.

  • Victor G. DEGTYAREV
    原稿種別: ORIGINAL ARTICLE
    2020 年 19 巻 1 号 p. 15-27
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル 認証あり

    The Hooded Crane Grus monacha remains the least known crane species in terms of its breeding range. Since 1985, typical wetlands meeting the characteristics of the typical Hooded Crane habitat have been surveyed between 56° and 66°N and between 108° and 136°E. Within the Lena River Basin, well-defined extensive breeding grounds of the Hooded Crane have been observed in the middle Aldan River Basin. Surveys of representative swampy headwaters, river reaches, and large watershed depressions, have revealed no other similar breeding grounds within the rest of the Lena River Basin, including areas attributed to the only known breeding grounds outside Manchuria. Within the extent of occurrence in the Lena River Basin and adjoining areas of the Olenyek, Khatanga and Yenisei river basins, breeding Hooded Cranes are presumably highly scattered. Solitary pairs are likely to breed hundreds of kilometers apart. Based on the distribution of wetlands, breeding grounds comparable to the middle Aldan River may occur in the basins of the upper Vilyui and the adjoining Moero and Kotui rivers. Evidence suggests that reports from local people are mostly plausible and consistent with maps and satellite images showing wetland habitat similar to that used by the Hooded Crane. Therefore, in the absence of direct data, the reports of the occurrence/nesting of Hooded Cranes beyond the Arctic Circle, particularly in the Olenyek River Basin quoted by Andreev (1974), should be given credence when delineating the breeding range. The region, including the Lena River Basin is too vast and difficult of access for aerial surveys to be practical. Tracking, based on navigation satellite systems, rather than stepwise ground surveys, is the only practical method for obtaining significant information over a short period of time.

  • R. Todd ENGSTROM, Lars EDENIUS, Tej B. THAPA, Basu BIDARI, Anil GURUNG ...
    原稿種別: ORIGINAL ARTICLE
    2020 年 19 巻 1 号 p. 29-40
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル 認証あり

    Maintaining biological diversity is an important objective at Chitwan National Park (CNP), the most visited national park in Nepal. Given human uses and manipulations of forests both in and around CNP, developing forest management guidelines that can both support human use of trees and sustain the biological diversity of the forests is a high priority. In February 2009 we measured bird communities with point counts, woodpecker abundance with playback, and collected vegetation data in Sal Shorea robusta and riverine forests in CHP and a nearby community forest to provide basic data on bird-habitat associations with an emphasis on woodpeckers. Riverine forest had over twice the density of trees per ha (many small trees), higher tree species richness, and greater basal area than Sal forest. Sal forest had more large trees than riverine forest. We detected 71 bird species during the point counts in the study forests, 18 more during playback sessions, and an additional 12 species that were more associated with adjacent habitats (e.g., wetlands or flying overhead) for a total of 101 species. Among resident species, 31% were primary or secondary tree-cavity nesters. On average for point counts, we detected 29.5 bird species (2.2 woodpeckers) on transects located in riverine forest and 23.3 bird species (1.8 woodpeckers) in Sal forests, but the difference was not statistically significant. While riverine forest had several commonly occurring species not detected in Sal forest, the opposite was not the case. The regression of woodpecker species richness against large tree density in both Sal and riverine forests was positive, but not statistically significant. As a method of sampling woodpeckers, playback resulted in approximately twice the number of individuals and species compared to detection from point counts.

  • Alima DORZHIEVA, Makoto NAKATA, Keisuke TAKANO, Youki FUJIHIKO, Yasuo ...
    原稿種別: ORIGINAL ARTICLE
    2020 年 19 巻 1 号 p. 41-53
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル フリー

    Changes in the timing of bird migration in spring and autumn in a coastal forest near the city of Niigata, central Honshu, Japan, were analyzed based on 27 years of bird-banding records. Half of the bird species studied, including all migratory types except residents, arrived or departed significantly earlier in spring due to an increase in spring temperatures. The rate of change we observed in spring migration timing due to changes in temperature was identical to or slightly greater than those reported in studies from other countries. The spring arrival of the Narcissus Flycatcher Ficedula narcissina and the Japanese Thrush Turdus cardis, both long-distance summer migrants to the nearby mountains, became earlier (advanced), however, for reasons that remained unclear. Median capture date in autumn was significantly associated with year for five species. Of these, the median capture date of the Japanese White-eye Zosterops japonicus, a resident and wandering bird, and the Black-faced Bunting Emberiza spodocephala, a wandering bird, advanced annually, while for the Japanese Robin Luscinia akahige and two other species (all long-distance migrants), it was delayed. We hypothesize that forest succession from a simple pine forest to a mixed forest with well-developed sub-canopy and shrub layers may have strongly influenced the Japanese White-eye and the Black-faced Bunting due to changes in population structure in the study area, resulting in an earlier median autumn capture date. Forest succession may also have influenced the Japanese Robin's food resources, enabling it to stay longer in the study area and resulting in a delay in autumn departure date. Thus, changes in bird migration timing differ according to different environmental factors in spring and autumn.

  • Shakeel AHMAD, Ejaz Ur REHMAN, Muhammad KABIR, Fathul BARI
    原稿種別: ORIGINAL ARTICLE
    2020 年 19 巻 1 号 p. 55-61
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル 認証あり

    White-rumped Vulture Gyps bengalensis colonies are expanding in some areas of their range after a catastrophic decline, yet in other areas population status and ecology remain poorly known. In the current study, we documented the first-ever monitoring of population size and nesting activity of the White-rumped Vulture using the road transect method in Kotli District, in Azad Jammu and Kashmir. Covering a 9.09 km road transect we found nine colonies, six of which had a total of 52 active nests (a mean of 5.8±5.6 nests per colony). The nine colonies contained a population of 191 vultures (a minimum of n=7, to a maximum of n=50 with a mean of 21.2±15 individuals per colony). Nests were on Chir Pine trees Pinus roxburghii at an average height of 20.8±1.6 meters from the ground. Most of the nests were near running water sources and roads. Vultures were found at waste from slaughterhouses, livestock carcasses, road-killed wildlife and street dogs, which appear to be their main sources of food. Forest fire could be detrimental to the species' population. Monitoring on an annual basis is needed in order to understand the population trend of the White-rumped Vultures in the area.

SHORT COMMUNICATION
TECHNICAL NOTES
  • Ivana NOVCIC
    原稿種別: TECHNICAL NOTES
    2020 年 19 巻 1 号 p. 107-113
    発行日: 2020年
    公開日: 2020/01/30
    ジャーナル 認証あり

    An important property of a foraging group is its density, particularly measured as nearest-neighbor distance. This study examined whether distance to the nearest neighbor changes over short time intervals in two fast-moving foragers, Dunlin Calidris alpina and Semipalmated Sandpiper C. pusilla, while at a spring stopover site in Delaware Bay, USA. For 181 focal individuals, nearest-neighbor distance was recorded in 5-s intervals for 60 seconds. For each focal individual, measured values were compared with those recorded at the beginning and end of observations, with the mean of values recorded at the beginning and end of observations, and with the mean of values recorded at the beginning, middle and end of observations. The results of this study indicate that single-point estimates of nearest-neighbor distance may not be appropriate in fast-moving foragers such as sandpipers.

feedback
Top