Kiyoaki Ozaki - Academia.edu (original) (raw)

Papers by Kiyoaki Ozaki

Frontiers in Marine Science

Marine protected areas (MPAs), particularly large MPAs, are increasing in number and size around ... more Marine protected areas (MPAs), particularly large MPAs, are increasing in number and size around the globe in part to facilitate the conservation of marine megafauna under the assumption that large-scale MPAs better align with vagile life histories; however, this alignment is not well established. Using a global tracking dataset from 36 species across five taxa, chosen to reflect the span of home range size in highly mobile marine megafauna, we show most MPAs are too small to encompass complete home ranges of most species. Based on size alone, 40% of existing MPAs could encompass the home ranges of the smallest ranged species, while only < 1% of existing MPAs could encompass those of the largest ranged species. Further, where home ranges and MPAs overlapped in real geographic space, MPAs encompassed < 5% of core areas used by all species. Despite most home ranges of mobile marine megafauna being much larger than existing MPAs, we demonstrate how benefits from MPAs are still li...

Marine Biology, 2020

Cyclones are currently increasing in frequency and intensity across the tropical regions, and suc... more Cyclones are currently increasing in frequency and intensity across the tropical regions, and such changes in cyclonic activity can adversely impact tropical marine ecosystems. To examine the potential effects of these changes on marine migrations, we tracked the annual at-sea distribution of black-naped terns from Okinawa Islands, southwest Japan (26.5° N; 127.9° E). Using light-based geolocation loggers, we compared the migration chronology of six terns between 4 years of contrasted conditions regarding cyclones (regionally called typhoons). Shortly after breeding (30 August ± 13.9 days), the birds undertook their migration across the Philippine Sea to coastal regions of Borneo and Sulawesi Islands, and seemed able to avoid or cross the storm systems. The two birds tracked in years of medium–high typhoon activity (2012–2014) seemed to target a stopover area in the northern Philippines several days after a typhoon hit. By contrast, in 2017, no strong typhoon hit in August and the four study birds showed later departure by 23.8 days, but moved significantly quicker, with little or no stopover. Arrival date at the wintering site was similar among years (1 October ± 3.5 days). Terns thus show remarkable variability in their migration chronology, presumably linked with annual storm frequency. However, the limits to this variability are currently unknown. Further, if individuals respond to environmental cues to time their migration to potentially benefit from lagged optimal feeding conditions en route, it is likely that the increase of back-to-back cyclonic events in the region may reduce the benefits of such a strategy for surface-feeding predators.

Ornithological Science, 2018

Japanese Journal of Ornithology, 2013

The Bulletin of the Japanese Bird Banding Association, 2010

1998～2000年に実施された日露共同標識調査の結果から，優占種，日周変化，再捕獲記録，主な種の渡り時期について解析した． ₃ 年間で合計46種5,278羽が標識放鳥され，21種361羽が再... more 1998～2000年に実施された日露共同標識調査の結果から，優占種，日周変化，再捕獲記録，主な種の渡り時期について解析した． ₃ 年間で合計46種5,278羽が標識放鳥され，21種361羽が再捕 montifringilla, migrated late. The data also showed that juveniles of Red-breasted Flycatcher, Rustic Bunting and Reed Bunting, which don＇t molt in the breeding area, migrated earlier than the adults, which molt completely in the breeding area. The juveniles of Common Rosefinch and Arctic Warbler, in contrast were found to migrate later than the adults, which molt in their wintering area. The captures and measurements obtained showed that the timing of body fat increase corresponded with the peak of migration in adults, but was about 10 days later in juveniles. This may account probably for juveniles taking a longer time to complete the migration than adults.

Ornithological Science, 2009

Journal of the Yamashina Institute for Ornithology, 1989

Journal of the Yamashina Institute for Ornithology, 2007

The ectoparasitic louse fly Ornithoica exilis (Diptera: Hippoboscidae) was collected from the Oki... more The ectoparasitic louse fly Ornithoica exilis (Diptera: Hippoboscidae) was collected from the Okinawa Rail Gallirallus okinawae (Gruiformes: Rallidae) in Okinawa Island, Japan. The present finding represents the first record of O. exilis from G. okinawae and from Okinawa Island.

Journal of the Yamashina Institute for Ornithology, 2003

Oryx, 2013

Many endemic species, particularly those on remote islands, have been driven to extinction or nea... more Many endemic species, particularly those on remote islands, have been driven to extinction or near extinction by anthropogenic influences. The short-tailed albatross Phoebastria albatrus once numbered in the millions but was thought to be extinct by the mid 20th century. Albatrosses, of the family Diomedeidae, are among the most threatened birds globally as a result of commercial exploitation, introduced predators, and mortality in commercial fisheries. We applied an experimental approach over 5 years to evaluate the translocation and hand-rearing of albatross chicks by comparing growth, physiological health indices, post-fledging survival, and migration patterns with a control group of naturally reared chicks in the source population. Hand-reared chicks had comparable or superior health and similar rates of immediate post-fledging mortality (15%), with mortality strongly female-biased in both groups. Hand-reared birds had longer post-fledging drift periods before attaining sustaine...

Ibis, 2002

... Mutsuyuki Ueta 1,* ,; David S. Melville 2,† ,; Ying Wang 3 ,; Kiyoaki Ozaki 4 ,; Yutaka Kanai... more ... Mutsuyuki Ueta 1,* ,; David S. Melville 2,† ,; Ying Wang 3 ,; Kiyoaki Ozaki 4 ,; Yutaka Kanai 1 ,; Paul J. Leader 2 ,; Chia-Chi Wang 3 ,; Chen-Yue Kuo 5. Article first published online: 19 APR 2002. ... 34, Alley 119, Lane 30, Yung-chi Road, 110, Taipei, Taiwan. ...

Genes & Genetic Systems, 2010

Ecological Research, 1998

Autumn migration routes of red-crowned cranes, Grus japonensis, from two continental east Asian s... more Autumn migration routes of red-crowned cranes, Grus japonensis, from two continental east Asian sites were documented in detail by satellite tracking. Two routes were identi®ed: a 2200 km western route from Russia's Khingansky Nature Reserve to coastal Jiangsu Province, China; and a 900 km eastern route from Lake Khanka (Russia) to the Korean Peninsula and the Demilitarized Zone. The most important rest-sites were identi®ed as Panjin Marsh (China), coastal mud¯ats southeast of Tangshan City (China), the Yellow River mouth (China), Tumen River mouth (North Korea/China/Russia), Kumya (North Korea) and Cholwon (Korean DMZ). Movements within the wintering range were also recorded, including complex commuting between sites by individual cranes and patterns of daily movements within sites. These data should prove useful for conservation of the¯yway.

Conservation Biology, 1996

Conservation Biology, 2004

Bird Conservation International, 2011

SummaryMany breeding colonies of Procellariiformes have been threatened with extinction. Chick tr... more SummaryMany breeding colonies of Procellariiformes have been threatened with extinction. Chick translocation has been shown to be an effective method for establishing new “safer” colonies of burrow-nesting species, but techniques for surface-nesting species have not been fully developed. The entire breeding population of the threatened Short-tailed Albatross Phoebastoria albatrus is restricted to two sites, Torishima Island and the Senkaku Islands, and neither site is secure due to volcanic activity or political instability. The Short-tailed Albatross Recovery Team has recommended facilitating the recovery of this species by establishing at least one additional colony through the translocation and hand-rearing of chicks at a safe historical breeding site. To evaluate the feasibility of this approach, we hand-reared 10 post-guard phase chicks of two related species in 2006–2007: Laysan Albatross P. immutabilis translocated from Midway Atoll to Kaua’i Island, Hawai’i and Black-footed ...

Biological Conservation, 2007

Deep Sea Research Part II: Topical Studies in Oceanography, 2006

We used satellite telemetry, remotely sensed data (bathymetry, chlorophyll a (chl a), sea-surface... more We used satellite telemetry, remotely sensed data (bathymetry, chlorophyll a (chl a), sea-surface temperature (SST), wind speed) and first-passage time (FPT) analysis to determine the distribution, movement patterns, and habitat associations of short-tailed albatrosses (Phoebastria albatrus) during the non-breeding season, 2002 and 2003. Satellite transmitters were deployed on birds immediately prior to their departure from a breeding colony at Torishima, Japan (n ¼ 11), or at-sea in the Aleutian Islands (n ¼ 3). Tracking durations ranged from 51 to 138 days for a total of 6709 locations after filtering (131-808 per bird). FPT (time required to transit a circle of given radius) revealed the location and spatial scale of arearestricted search (ARS) patterns along flight paths. On average, ARS occurred within 70 km radii. Consequently, the fit of the habitat use models increased at spatial scales beyond a 40 km FPT radius (R 2 ¼ 0:31) and stabilized for scales of 70 km and larger (R 2 ¼ 0.40-0.51). At all scales, wind speed, depth or depth gradient, and chl a or chl a gradient had a significant effect on FPT (i.e., residence time). FPT increased within regions of higher gradients of depth and chl a. In contrast, FPT decreased within regions of greater depth and wind speed, with a significant interaction of wind speed and depth at some scales. Sea-surface temperature or its interactions were only significant at large spatial scales (X160 km FPT radius). Albatrosses engaged in ARS activities primarily over the shelf break and slope, including Kuroshio and Oyashio regions off the western subarctic gyre. Occasionally, birds transited the northern boundary of the Kuroshio Extension while inroute to the Aleutian Islands and Bering Sea, but overall spent little time in the western gyre. In the Aleutian Islands, ARS occurred within straits, particularly along the central and western part of the archipelago. In the Bering Sea, ARS occurred along the northern continental shelf break, the Kamchatka Current region, and east of the Commander Islands. Nonbreeding short-tailed albatross concentrate foraging in oceanic areas characterized by gradients in topography and water column productivity. This study provides an understanding of the foraging ecology for a highly migratory, imperiled