Conservation Ecology of Indo-Pacific bottlenose dolphins in Amakusa, western Kyushu, Japan

日本九州西部天草的印度太平洋宽吻海豚的保护生态

• 批准号: 13660182
• 负责人: SHIRAKIHARA Kunio
• 金额: $ 2.3万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13660182/
• 关键词: Indo-Pacific bottlenose dolphin; Tsujishima island; Nagashima island; habitat shift; individual recognition; population estimation; habitat utilization; 個体識別; 個体数推定; 海域利用; ハンドウイルカ; 個体数

A year-round resident population of bottlenose dolphins is known to inhabit the coastal waters of Amakusa, western Kyushu, Japan. We confirmed that most of individuals moved in 2000 from waters near Tsujishima Island in Kumamoto prefecture to Nagashima Island in Kagoshima prefecture. Distance between both islands is 60 km. At the beginning, the objective of this study was to investigate causes of such habitat shift, but they returned to Tsujishima in 2001 and only a portion of individuals has remained near Nagashima. Recent taxonomic re-examinations has shown that botllenose dolphins are separated into two species : Tursiops aduncus and T. truncatus. We needed to identify the species of bottlenose dolphins off Amakusa. The final objectives of this study on bottlenose dolphins in the coastal waters of Amakusa were 1) to identify the species. 2) to estimate the population size and 3) to clarify their habitat utilization.Morphological and genetic examination of specimens showed that the species is T. aduncus (Shirakihara et al. 2003). We estimated that the population size was 218 individuals using techniques of photo-identification and mark-recapture (Shirakihara et al. 2002). Behavioral observation and theodolite tracking showed as follows. In the daytime, this population utilizes shallow waters with depth less than 20 m and tends to move regularly along the coast. We guessed that in the daytime it takes rest and from near sunset it begins to move to the waters suitable for conducting night activities, which are not the open sea facing East China Sea.This population is subject to negative stress from dolphin watching. To evaluate whether the population size will decrease or not is an important work to continue in future.

在日本九州西部的天草（阿马库萨）沿岸沃茨，全年都有瓶鼻海豚的栖息地。2000年，大部分个体从熊本县的筑岛岛附近沃茨迁移到鹿儿岛县的长岛岛。两岛之间的距离为60公里。本研究最初的目的是调查这种栖息地转移的原因，但它们在2001年返回了筑岛，只有一部分个体留在了长岛附近。最近的分类学研究表明，瓶鼻海豚可分为两个种：Tursiops aduncus和T. truncatus)(采自菜豆)。我们需要鉴定阿马库萨海域宽吻海豚的种类。本研究的最后目的是鉴定阿马库萨沿岸沃茨的瓶鼻海豚的种类。2)3）阐明其生境利用情况。aduncus（Shirakihara等人，2003）。我们使用照片鉴定和标记再捕获技术估计种群大小为218只（Shirakihara等人，2002）。性状观测及经纬仪跟踪显示如下。在白天，该种群利用水深小于20米的浅水沃茨，并倾向于沿着海岸有规律地移动。我们推测，它们在白天休息，从接近日落时开始向适合夜间活动的沃茨移动，这些水域不是面向东海的公海，该种群受到观赏海豚的负面压力。对种群规模是否会下降进行评估是今后一个重要的工作。

项目成果

Shirakihara M, Shirakihara K, Tomonaga J, Takatsuki M: "A resident population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Amakusa, western Kyushu, Japan."Marine Mammal Science. 18(1). 30-41 (2002)

Shirakihara M、Shirakihara K、Tomonaga J、Takatsuki M：“日本九州西部天草的印度太平洋宽吻海豚 (Tursiops aduncus) 的常驻种群。”海洋哺乳动物科学。

Shirakihara. M., H. Yoshida and Shirakihara. K.: "Indo-Pacific bottlenose dolphins Tursiops aduncus in Amakusa, western Kyushu, Japan"Fisheries Science. in press.

白木原。

Shirakihara K., Okamura H. & Kasamatsu F.: ""Kaisan honyurui no chousa to hyouka", translated "Marine mammal survey and assessment methods"into Japanese , Special publication"The Institute of Cetacean Research, Tokyo. No.9

白木原 K.、冈村 H.

Shirakihara M, Shirakihara K et al.: "A resident population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Amakusa, western Kyushu, Japan"Marine Mammal Science. 18.1. 30-41 (2002)

白木原 M、白木原 K 等人：“日本九州西部天草的印度太平洋宽吻海豚 (Tursiops aduncus) 的常住种群”海洋哺乳动物科学。

白木原国雄ほか2名(監訳): "海産哺乳類の調査と評価"日本鯨類研究所(鯨研叢書,No.9). 169 (2002)

白木原邦夫等2人（指导翻译）：《海洋哺乳动物的调查与评价》日本鲸类研究所（Chale Research Series，No.9）（2002年）。