• Title/Summary/Keyword: Pacific island

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Geochemistry and K-Ar Age of Alkali Basalts from Weno Island, Caroline Islands, Western Pacific (서태평양 캐롤라인군도 웨노섬 알칼리 현무암류의 지구화학 및 K-Ar 연대)

  • Lee, Jong-Ik;Hur, Soon-Do;Park, Byong-Kwon;Han, Sang-Jun
    • Ocean and Polar Research
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    • v.23 no.1
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    • pp.23-34
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    • 2001
  • Geochemical and Sr-Nd isotopic compositions and K-Ar ages are analyzed in volcanic rocks from Weno Island, Caroline Islands. Seven Weno lava samples of alkali basalt and basaltic trachyandesite are aphyric or sparsely phyric comprising olivine, plagioclase, and clinopyroxene phenocrysts. Whole-rock geochemical variation of Weno lavas reflects main fractional crystallization of olivine and Cr-spinel phenocrysts. Newly determined K-Ar ages of Weno lavas range from 6.7 to 11.3 Ma (late Miocene), indicating their formation during primary volcanic stage of Chuuk Islands. Trace element compositions of Weno lavas are very similar to those of typical ocean island basalts (OIBs), suggesting their formation during intra-plate mantle plume activity. The plume composition is isotopically very similar to that of Hawaiian hot spot. However, the age span of Chuuk volcanism is longer than that of the other individual volcanoes in the Pacific.

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Copepods of the family Kelleriidae (Crustacea, Copepoda, Cyclopoida) from tropical waters of the Asia-Pacific

  • Hong, Jae-Sang;Kim, Il-Hoi
    • Journal of Species Research
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    • v.10 no.4
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    • pp.364-386
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    • 2021
  • Six species of the family Kelleriidae, including four new species, are recorded from tropical waters of the Asia-Pacific, two of them from Phuket Island, Thailand, one each from Bohol Island, Philippines and Phu Quoc Island, Vietnam, and two from Kosrae Island, Micronesia. A new genus Kelleriella is proposed to accomodate one of these new species (Kelleriella quadridens n. sp.). There are three diagnostic features of the new genus: the terminal segment of antenna is armed with one strong claw and six setae, the armature of the maxilliped endopod is reduced, and the third exopodal segment of leg 4 is armed with four spines and five setae. The other three new species are Kelleria latipes n. sp., Kelleria phuketensis n. sp., and Kelleria robusta n. sp. As diagnostic features of these new species, their caudal rami are about 2.5, 3.2, and 1.72 times longer than wide, respectively, the exopod of leg 5 of them is smooth, without any process, about 1.9, 3.7, and 2.9 times longer than wide, respectively, and armed with one spine plus one seta in Kelleria latipes and Kelleria phuketensis or with 2 setae in Kelleria robusta. Additionally, Kelleria javaensis Mulyadi, 2009 is synonymized with Kelleria regalis Gurney, 1927 and Kelleria grandisetiger Kim, 2006 is synonymized with Kelleria andamanensis Sewell, 1949, and both species are redescribed.

Decapod Crustaceans of Dokdo Island, Korea

  • Hong Byung-Kyu;Kim Mi-Hyang;Kim Jung-Nyun;Jeon Kyeong-Am
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.39 no.spc1
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    • pp.252-258
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    • 2006
  • Thirteen decapod crustaceans of Dokdo Island were identified and classified based on samples collected around Dokdo Island from May 1999 to November 2004. Of the 13 species, 7 were unrecorded from Dokdo Island: Axiopsis princeps, Pagurus angustus, Pagurus japonicus, Pagurus nigrivittatus, Pagurus spina, Portunus trituberculatus, and Hemigrapsus penicillatus. Of these 7 species, Pagurus nigrivittatus and Pagurus spina were new to the Korean decapod fauna. However, P. spina was only reported as the type series from the Pacific coast of northern Japan. Its geographic range now extends to the East Sea. To date, 25 decapod crustaceans (1 caridean, 1 thalassinidean, 11 anomurans, and 12 brachyurans) have been reported from Dokdo Island.

Distribution Status of Indo-Pacific Bottlenose Dolphin Tursiops aduncus in the Jeju Island Based on Social Media Data (소셜 미디어 정보를 활용한 제주도 남방큰돌고래(Tursiops aduncus)의 분포 현황 파악)

  • Kim, Hyun Woo;Lee, Dasom;Sohn, Hawsun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.51 no.5
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    • pp.600-605
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    • 2018
  • The Indo-Pacific bottlenose dolphins Tursiops aduncus are the only cetacean species that can be observed visually on coastal areas of Jeju Island and regarded as one of valuable tour resources. We attempted to figure out location and timing information of the dolphin sightings collected from two major social media, Naver $Caf{\acute{e}}$ and Instagram. 142 of dolphin sighting information were derived from 2,501 dolphin related postings on Naver $Caf{\acute{e}}$ between 2004 to 2017. 292 informative postings also were found on Instagram through hashtag searching. The number of posts about dolphin sighting was not frequent until 2014. Since 13 posts were found in 2014, dramatic increase of the sighting numbers was accelerated as 38 in 2015, 93 in 2016 and 269 in 2017. 195 (45.7%) from coastal area of Daejeong-eup, south-western part of the Island, were posted. The number of dolphin sightings also high from Gujwa-eup(n=50, 11.7%), Hangyeong-myeon (n=49, 11.5%), Seongsan-eup (n=38, 8.9%) and Seogwipo-si (n=34, 8.0%). Our results show that social media data has a high potential to be used as a data source for study of distribution pattern of the dolphins.

Marine Mollusk Fauna of Kosrae Island, Federated States of Micronesia

  • Lee, Sang-Hwa;Park, Joong-Ki
    • The Korean Journal of Malacology
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    • v.29 no.4
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    • pp.343-376
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    • 2013
  • The Federated States of Micronesia consists of four states of Yap, Chuuk, Pohnpei and Kosrae, which are located in the West Pacific Ocean. In order to investigate molluscan fauna of Kosrae Island, field survey was made twice from 21st to 30th of January, 2011 and from 6th to 17th of January, 2012 for four localities including 10 intertidal and 14 subtidal zones of Kosrae Island. The mollusk samples collected were identified based on their morphological characteristics, comprising a total of 120 species from 30 families through this survey. In this study, we provided species list and illustrations for 120 species identified, and combined these with the previous record, resulting in a total of 208 species from 47 families in Kosrae Island.

A New Record of Smittinid Bryozoa (Gymnolaemata, Cheilostomata) from Manjae Island, Korea (만재도의 한국 미기록 입이끼벌레류(나후강, 순구목) 1종)

  • Seo, Ji-Eun
    • Animal Systematics, Evolution and Diversity
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    • v.18 no.1
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    • pp.135-141
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    • 2002
  • One of bryozoans collected from the subtidal zone of Manjae Island on Aug. 23, 1988 was identified. Parasmittina delicatula (Busk, 1884) turned out to be new to the Korean fauna. Therefore, twelve bryozoan species are reported from Manjae Island so far. Ten species including the present one among them were recorded only from the Pacific Ocean. They consisted of four tropical, three cold temperate and four endemic species to Korea and Japan. It is quite probable that Manjae Island, which is influenced by both warm and cold water currents, seems to be unique and significant area in terms of marine zoogeography.

Population persistence of the perennial kelp Eisenia arborea varies across local spatial scales

  • Gossard, Daniel J.;Steller, Diana L.
    • ALGAE
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    • v.37 no.1
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    • pp.63-74
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    • 2022
  • Perennial stipitate kelps are globally distributed and individual species can inhabit broad latitudinal ranges, expressing notably longevous persistence. Despite the foundational role kelps provide to their communities, little is known about the variability in persistence of the stipitate kelps at local spatial scales. We studied the population persistence of Eisenia arborea, a heat- and wave force-tolerant perennial stipitate kelp with a distributional range extending from British Columbia to south of the range limit of all other northeast Pacific kelps, in Baja California Sur, Mexico. Persistence characteristics for E. arborea among sites were compared and used to test the hypothesis that stand persistence varied at local spatial scales around Isla Natividad, a Pacific island off the Baja California peninsula with documented spatiotemporal environmental heterogeneity. Collected individuals around the island were "aged" using the previously validated age estimation technique of counting annual cortical dark rings. After detecting no significant differences among sites in the covariation between estimated ages for collected individuals and stipe length, we utilized in-situ population-level stipe length measurements to more rapidly predict age structures within six stands around the island. Predicted age structures, and associated stand densities, revealed persistence characteristics and density varied at local scales and a strong positive relationship existed between stand density and stand mean and maximum ages. We speculate that stands responded differently to deterministic influences (e.g., the 2014-2016 marine heatwave and / or competition with Macrocystis) resulting in heterogenous local persistence of this foundation species.

First Reliable Record of Bregmaceros nectabanus (Gadiformes; Bregmacerotidae) from Jeju-do Island of Korea, with a Key to Species of Eight Bregmacerotids from the Northwestern Pacific (한국 제주도에서 날개멸과(대구목) 어류, Bregmaceros nectabanus의 첫 출현 및 북서태평양 날개멸과 8종의 종검색)

  • Jang, Seo-Ha;Kim, Jin-Koo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.3
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    • pp.340-349
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    • 2021
  • Three specimens (33.6-44.8 mm in standard length) of the family Bregmacerotidae, collected from the waters off south-western Jeju-do Island in October 2016, were identified as Bregmaceros nectabanus on the basis of morphological and molecular methods (DNA barcoding). This species is characterized by having 50-52 2nd dorsal fin rays, 52-53 anal fin rays, 13 principal caudal fin rays, an unpigmented abdomen, irregularly distributed dorsal chromatophores, and the origin of a dorsal fin slightly behind the anal fin. This is the first reliable record of B. nectabanus in Korea. According to Yoo et al. (1992), we propose a Korean name "Tae-Pyeong-Yang-Nal-Gae-Myeol" for this species. Also, we suggest key to species of these eight bregmacerotids from the northwestern Pacific.

A Systematic Review of Cervical Cancer Incidence and Mortality in the Pacific Region

  • Obel, J.;Souares, Y.;Hoy, D.;Baravilala, W.;Garland, S.M.;Kjaer, S.K.;Roth, A.
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9433-9437
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    • 2014
  • This study provides the first systematic literature review of cervical cancer incidence and mortality as well as human papillomavirus (HPV) genotype prevalence among women with cervical cancer in the Pacific Island countries and territories. The cervical cancer burden in the Pacific Region is substantial, with age standardized incidence rates ranging from 8.2 to 50.7 and age standardized mortality rate from 2.7 to 23.9 per 100,000 women per year. The HPV genotype distribution suggests that 70-80% of these cancers could be preventable by the currently available bi- or quadrivalent HPV vaccines. There are only few comprehensive studies examining the epidemiology of cervical cancer in this region and no published data have hitherto described the current cervical cancer prevention initiatives in this region.

Development of High-Resolution Pacific Ocean Circulation Model

  • You Sung-Hyup;Yoon Jong-Hwan;Seo Jang-Won;Youn Yong-Hoon
    • 한국전산유체공학회:학술대회논문집
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    • 2006.05a
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    • pp.129-132
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    • 2006
  • A Pacific Ocean circulation model based on the RIAM Ocean Model (RIAMOM) with $1/6^{\circ}C\;and\;1/12^{\circ}C$ horizontal resolution successfully reproduced the peculiar circulation structures of the Pacific Ocean. The volume transports of model agree very well with the results of observations in the northwestern Pacific Ocean. Also our model successfully reproduced the observed structures of the northeastward Ryukyu Current with a subsurface core at $500{\sim}600m$. A Possible mechanism for the subsurface current core of the Ryukyu Current is proposed focusing on the blocking effect of the Ryukyu Island Chain.

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