文献一覧: 神田育子 (著者)

7 0 0 0 OA 伊勢湾西岸における2011~2020年のスナメリのストランディングに関する記録

著者: 神田育子古山歩若林郁夫若井嘉人船坂徳子吉岡基 Kanda Ikuko Furuyama Ayumi Wakabayashi Ikuo Wakai Yoshito Funasaka Noriko Yoshioka Motoi
出版者: 三重大学大学院生物資源学研究科
雑誌: 三重大学大学院生物資源学研究科紀要 = The bulletin of the Graduate School of Bioresources Mie University
巻号頁・発行日: vol.47, pp.13-23, 2021-12

In this study, we aimed at clarifying the recent trends in narrow-ridged finless porpoise stranding on the west coast of Ise Bay. We analyzed the annual/monthly change in the number of stranded individuals, the status found, the length and sex of the individuals, and the seasonality of the geographical distribution data from 486 individuals collected along the northern central coast of Mie Prefecture for 10 years from January 2011 to December 2020. The annual number of stranded individuals fluctuated between 2011 and 2015, although it was stably around 60 individuals after 2016 when a local stranding network of universities, aquariums, museums, and local governments were established. As for the status of stranding, 96.5% of the individuals were found alone and they were dead except one. More males were observed among the stranded individuals than females with a sex ratio of 1.4. The body length frequency data showed that 75-85 cm individuals, approximately of birth length, accounted for 51.1% and 39.1% in the male and female groups, respectively, and stranding during the newborn period was overwhelmingly predominant. Several individuals below the birth length were found in April-July while the peak of calving season was considered to be April-June. The monthly number of stranded individuals peaked in May-June every year, and dead newborn calves were major factors in boosting the number of stranded individuals found during this period. The geographical distribution of stranded individuals displayed seasonal changes. Most stranded animals were recorded in the central part of the west coast of Ise Bay in April-June, exhibiting a gradual decrease and becoming scarce by January-March.

2022-02-18 07:06:10
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http://hdl.handle.net/10076/00020215

1 0 0 0 大阪湾におけるスナメリの分布と密度

著者: 近藤茂則神田育子石田義成鍋島靖信
出版者: 日本哺乳類学会
雑誌: 哺乳類科学 (ISSN:0385437X)
巻号頁・発行日: vol.50, no.1, pp.13-20, 2010-06-30
参考文献数: 20

大阪湾におけるスナメリNeophocaena phocaenoidesの分布と密度を把握するために,大阪府環境農林水産総合研究所の海洋調査船「おおさか」によるスナメリ目撃記録の分析を行うと共に,湾中部海域を航行するカー・フェリーを用いてライントランセクト法による目視調査を実施した.海洋調査船「おおさか」は,2004年4月~2007年12月の期間における263日間に,合計25群のスナメリに遭遇していた.同船は大阪湾の広い海域を航行していたが,スナメリは岬町~岸和田市沖の湾東部海域(34°21′~32′N,135°8′~20′E)でのみ目撃されていた.また,カー・フェリーからの目視調査では,2005年10月~2007年1月の期間に,Beaufort風力階級2以下の海況下を4,403 kmにわたって調査し,合計72頭のスナメリを発見した.発見位置は,湾東部海域(34°23′~26′N,135°8′~13′E)に集中していた.スナメリの密度は,3~7月に高い値を示す傾向があった.ピークの4月における密度は,0.238頭/km2と推定された.これらのことから,スナメリは,大阪湾東部の限られた海域に主に分布しており,春~初夏にかけてこの海域に多く来遊すると考えられた.

2021-08-03 17:50:16
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