著者
Annette L. Fayet Masaki Shirai Sakiko Matsumoto Aimee Van Tatenhove Ken Yoda Akiko Shoji
出版者
The Ornithological Society of Japan
雑誌
ORNITHOLOGICAL SCIENCE (ISSN:13470558)
巻号頁・発行日
vol.18, no.2, pp.189-195, 2019 (Released:2019-07-29)
参考文献数
37
被引用文献数
1

To identify drivers of local variation in breeding success in colonial seabirds, we studied the role of breeding phenology and parental quality on the breeding performance of two neighbouring subcolonies of Streaked Shearwaters Calonectris leucomelas, with similar habitat but different success. Egg dimension and parental quality during incubation, but not phenology, predicted hatching success. Birds at the low-success colony laid smaller eggs, reared smaller chicks and neglected eggs more frequently, leaving them vulnerable to predation. Our findings suggest that local variation in breeding performance in this species arises from differences in breeding quality, perhaps driven by age or experience.
著者
Miho SAKAO Tomoko HAMABATA Katsufumi SATO Shinichi WATANABE Ken YODA Kozue SHIOMI
出版者
The Ornithological Society of Japan
雑誌
ORNITHOLOGICAL SCIENCE (ISSN:13470558)
巻号頁・発行日
vol.22, no.2, pp.111-121, 2023 (Released:2023-08-01)
参考文献数
66
被引用文献数
1

The genetic structure of Streaked Shearwater Calonectris leucomelas, a seabird breeding on islands around Japan, was investigated using nuclear microsatellite markers at four breeding colonies located in three geographically distinct areas (Pacific Ocean, Sea of Japan, and Seto Inland Sea). To investigate independently natal and breeding dispersal patterns, we analyzed records of recoveries of birds banded around Japan over a 30-year period from 1971 to 2020. The genetic marker analysis showed little differentiation among the breeding sites and a lack of population structure. In contrast, banding data presented few examples of natal and breeding dispersal and a much greater number of natal/breeding philopatry cases. Although further research is needed to understand the discrepancy between the genetic properties and recapture patterns of banded birds, some possible reasons are suggested: actual dispersal events may not have been fully detected by the banding research, thus, underestimating dispersal frequency; rare dispersal events may have functioned to reduce the genetic structure; and/or breeding colonies of this species might have been established recently, thus genetic markers may not be indicative of current dispersal patterns. In conclusion, our results indicate ongoing gene flow and/or strong historical association in this species.
著者
Takashi Yamamoto Hiroyoshi Kohno Akira Mizutani Hanako Sato Hiroki Yamagishi Yutaka Fujii Miku Murakoshi Ken Yoda
出版者
The Ornithological Society of Japan
雑誌
ORNITHOLOGICAL SCIENCE (ISSN:13470558)
巻号頁・発行日
vol.16, no.1, pp.17-22, 2017 (Released:2017-03-01)
参考文献数
42
被引用文献数
14

There is increasing evidence showing that wind velocity affects the flight and foraging behavior of seabirds; however, few studies have examined these effects on seabirds inhabiting tropical oceans where lighter wind conditions usually prevail. The Brown Booby Sula leucogaster is an example of a tropical seabird with relatively low wing loading; strong wind conditions may be expected to impede the stability of their flight. We examined how different wind conditions affected the duration and flying behavior of Brown Booby fledglings during foraging trips by means of direct observation of nest attendance and by attaching video loggers to birds. The duration of foraging trips by fledglings decreased with increasing wind speed, and during flight, the body rotation of fledglings became greater with increasing wind speed. As expected, fledglings were buffeted by strong winds due to their relative inexperience in flight combined with their low wing loading. Fledglings were probably forced to flap against strong winds in order to adjust the stability of their bodies, offsetting the efficient use of wind for gliding. Furthermore, the height at which fledglings flew fluctuated more at higher wind velocities, which may have constrained their detection and capture of prey. In conclusion, our results indicate that the aerodynamic performance of Brown Booby fledglings is impaired by strong wind conditions, leading to poor flight stability and potentially reduced prey detection.