奄美大島の役勝川におけるリュウキュウアユの遡上生態

• 岸野 底

• 四宮 明彦

書誌事項

タイトル別名

• Upstream migration of Ryukyu-ayu Plecoglossus altivelis ryukyuensis in the Yakugachi River, Amami-oshima Island, Japan
• アマミ オオシマ ノ ヤクガチガワ ニ オケル リュウキュウアユ ノ ソジョウ セイタイ

抄録

The Ryukyu-ayu Plecoglossus altivelis ryukyuensis, whose population is steadily declining, inhabits only limited areas of the Ryukyu Islands in southern Japan. The period, body size, age and developmental stage at upstream migration of larvae and juveniles of Ryukyu-ayu were investigated in the Yakugachi River in Amami-oshima Island in 1994 and 1996. The upstream migration lasted for four months from late January to late May. The range of standard length was 24.4-46.7 mm (average±SD=35.2±3.36), and the range of ages 54-128 days (83.7±15.4). Developmental stages were composed of seven steps from the "whitebait" larvae stage to juvenile stage having comb-like teeth in the jaws. Usptream migrating Ryukyu-ayu were characterized by a smaller size, a younger age and an earlier developmental stage, compared with ayu Plecoglossus altivelis altivelis. Those charactersistics seemd attributable to a shorter period of coastal life befor upstream migration.

収録刊行物

• 日本水産学会誌

  日本水産学会誌 69 (4), 624-631, 2003

  公益社団法人 日本水産学会

キーワード

• リュウキュウアユ
• 遡上時期
• 体長
• 日齢
• 発育段階
• 奄美大島
• 緯度的傾斜

詳細情報

• CRID: 1390001206415016192
• NII論文ID: 110003145561
• NII書誌ID: AN00193422
• DOI: 10.2331/suisan.69.624
• ISSN: 1349998X
• ISSN: 00215392
• ISSN: http://id.crossref.org/issn/00215392
• NDL書誌ID: 6652786
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6652786
• Web Site: http://dl.ndl.go.jp/info:ndljp/pid/11076496
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • NDL-Digital
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可