タイトル |
瀬戸内海燧灘におけるヒラメ着底仔稚魚の餌料環境と摂餌生態 |
担当機関 |
香川県水産試験場 |
研究期間 |
2001~2004 |
研究担当者 |
山本昌幸 香川県水産試験場
|
発行年度 |
2004 |
背景・ねらい |
瀬戸内海において400万尾以上の種苗が放流され、約1000tが毎年漁獲されている重要資源であるヒラメの着底場所の餌料環境および着底初期の摂餌生態を解明する。
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成果の内容・特徴 |
日本海や太平洋に比べて知見の乏しい瀬戸内海のヒラメの着底場所の餌料環境および着底初期の摂餌生態を1999~2001年に調べた。
- 瀬戸内海燧灘では、日本海や太平洋に比べてアミ類の密度が低い一方、エビジャコ(Crangon spp.)の密度は非常に高かった。(表1)
- エビジャコの密度は高いものの、ほとんどが小型のエビジャコ(体長18mm以下)であり、ヒラメ着底仔魚を捕食する可能性のある体長25mm以上のエビジャコの密度は非常に低かった。(図1)
- ヒラメ着底仔稚魚の胃内容物組成(重量%)をみると、着底直後はアミ類、ヨコエビ類の割合が高かったが、成長に伴いヨコエビ類の割合が減り、一方エビジャコの割合が増加した。そして、全長50mm以上になるとハゼ類、ネズッポ類などの魚類が出現した。(図2)
- 本海域においてエビジャコはヒラメの捕食者でなく、被食者として重要であった。
- ヒラメ稚魚は、エビジャコや潜砂性のアミ(Iiella oshimai)より、表在性のアミ(Nipponmysis ornata、Anisomysis ijimai)を好んで摂餌していた。(表2)
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成果の活用面・留意点 |
- 瀬戸内海のヒラメ稚魚にとってエビジャコは、アミ類に次ぐ重要な餌生物であることから、小型のエビジャコの密度がヒラメ稚魚の生残に大きく関与する。
- 砂浜域の生態系解明の基礎知見として活用される。
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図表1 |
![229557-1.png](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/229557-1.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECsaDmFwLW5vcnRoZWFzdC0xIkcwRQIhAPqlCKiamRxLtyKfyXcjrH6FPZN9b4qXmfZkK%2BSZ5WMlAiAYHPMqY7crChF7xnk3PMJrKDAluFGRrcwdY0Ops%2FkhwiqZBAjV%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAIaDDUzMjMzMTA3MjA0MSIM7VG%2FtaSAIoR6Fa3aKu0DJObNvPirEZpfYkFZTByRJ%2BlLX1g8Y%2F9S15gDPGRfrEY2mm2a24TUMn4TcAMOOo%2Fk%2BQal309owhqz2PkQXUFR0GWXpb8M84yVYf2bJoyoWDz%2FVSTWCBBoEIWlJK9v8tFLaZX5Qw1L00l9bFx0tEIpxAW6Be7Yr72hxORlSRWcealo41wpK%2BEU6NwtYBZGWt1EsUSVc2MCgsqDMGaHhrlM95gCqAjizkI2tY5dUD0dYVPcga9dvD5ROfpmQD0uGAEkNSyRPdpc4tW%2BUi7RI9BMYhB6vN%2Bo4Z%2FnQKdzT9krpwxsrQiw0yydh45cch3gDL2qe8dgcqHdpS1GdeSpON%2BkZFlP6vY%2FkuWtH8F4DEClKr1QXeIQ4VPYj58jyfcBoSgyAMMgL97jdx%2FBAaAXscn73FQ8wD8ts9HRMQ%2FpR4ypxUvZZLh%2FI1J%2F1OcGKSL1%2Fh2p6PZK5TF7zvby370M1YXqsd4xoXzwcP8dPPCJJlDMD76xSfm4UjwD%2FImRjYlhnqIeykti2nuqKzKJuPFAoV%2BFDlQNXXtpBbGjddPg5XFCC1brUNEuHXIiapMlWHwdADvq%2FBPozgyCOJCEN%2BoJzXBNk1ctcHxr2DBZfEC01Jdui9jF46mWJJS957JHQ3oVERwefgcIpWJRH3ZcaHfhcDCN9u%2BzBjqmAYsCLszALtdlfvJbXxtRTsN3P1KnSpu%2BxHyZ4rdOX3VK7kIoXOse8vDhTc8A2LdIaAVUMvoAt1JLbuBLhdKJd%2FpVraYL8phd5Wb1PT9wo%2BjAE7pe4rtgTkHzLU8Ql70CscQILZVWpDD8Moe12XoXSKb%2F%2FqcnQqIiFXnrb2tSna3zr6NWV6kUnHNBKEiiKhqtHtFSXj6s61POpjWlTy7gWmtoTHyxigQ%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIU62WQFX7A%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T113946Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=41c3a05cd18913f08f08a43f3beb3665f42a06e6b59f0a46f0a53fbd7e6a3f59) |
図表2 |
![229557-2.png](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/229557-2.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECsaDmFwLW5vcnRoZWFzdC0xIkcwRQIhAPqlCKiamRxLtyKfyXcjrH6FPZN9b4qXmfZkK%2BSZ5WMlAiAYHPMqY7crChF7xnk3PMJrKDAluFGRrcwdY0Ops%2FkhwiqZBAjV%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAIaDDUzMjMzMTA3MjA0MSIM7VG%2FtaSAIoR6Fa3aKu0DJObNvPirEZpfYkFZTByRJ%2BlLX1g8Y%2F9S15gDPGRfrEY2mm2a24TUMn4TcAMOOo%2Fk%2BQal309owhqz2PkQXUFR0GWXpb8M84yVYf2bJoyoWDz%2FVSTWCBBoEIWlJK9v8tFLaZX5Qw1L00l9bFx0tEIpxAW6Be7Yr72hxORlSRWcealo41wpK%2BEU6NwtYBZGWt1EsUSVc2MCgsqDMGaHhrlM95gCqAjizkI2tY5dUD0dYVPcga9dvD5ROfpmQD0uGAEkNSyRPdpc4tW%2BUi7RI9BMYhB6vN%2Bo4Z%2FnQKdzT9krpwxsrQiw0yydh45cch3gDL2qe8dgcqHdpS1GdeSpON%2BkZFlP6vY%2FkuWtH8F4DEClKr1QXeIQ4VPYj58jyfcBoSgyAMMgL97jdx%2FBAaAXscn73FQ8wD8ts9HRMQ%2FpR4ypxUvZZLh%2FI1J%2F1OcGKSL1%2Fh2p6PZK5TF7zvby370M1YXqsd4xoXzwcP8dPPCJJlDMD76xSfm4UjwD%2FImRjYlhnqIeykti2nuqKzKJuPFAoV%2BFDlQNXXtpBbGjddPg5XFCC1brUNEuHXIiapMlWHwdADvq%2FBPozgyCOJCEN%2BoJzXBNk1ctcHxr2DBZfEC01Jdui9jF46mWJJS957JHQ3oVERwefgcIpWJRH3ZcaHfhcDCN9u%2BzBjqmAYsCLszALtdlfvJbXxtRTsN3P1KnSpu%2BxHyZ4rdOX3VK7kIoXOse8vDhTc8A2LdIaAVUMvoAt1JLbuBLhdKJd%2FpVraYL8phd5Wb1PT9wo%2BjAE7pe4rtgTkHzLU8Ql70CscQILZVWpDD8Moe12XoXSKb%2F%2FqcnQqIiFXnrb2tSna3zr6NWV6kUnHNBKEiiKhqtHtFSXj6s61POpjWlTy7gWmtoTHyxigQ%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIU62WQFX7A%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T113946Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=433797b7bd79d2eaaa2f93d43ef152f8700f6782bd798fa47c5dcb0d61df27f0) |
図表3 |
![229557-3.png](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/229557-3.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECsaDmFwLW5vcnRoZWFzdC0xIkcwRQIhAPqlCKiamRxLtyKfyXcjrH6FPZN9b4qXmfZkK%2BSZ5WMlAiAYHPMqY7crChF7xnk3PMJrKDAluFGRrcwdY0Ops%2FkhwiqZBAjV%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAIaDDUzMjMzMTA3MjA0MSIM7VG%2FtaSAIoR6Fa3aKu0DJObNvPirEZpfYkFZTByRJ%2BlLX1g8Y%2F9S15gDPGRfrEY2mm2a24TUMn4TcAMOOo%2Fk%2BQal309owhqz2PkQXUFR0GWXpb8M84yVYf2bJoyoWDz%2FVSTWCBBoEIWlJK9v8tFLaZX5Qw1L00l9bFx0tEIpxAW6Be7Yr72hxORlSRWcealo41wpK%2BEU6NwtYBZGWt1EsUSVc2MCgsqDMGaHhrlM95gCqAjizkI2tY5dUD0dYVPcga9dvD5ROfpmQD0uGAEkNSyRPdpc4tW%2BUi7RI9BMYhB6vN%2Bo4Z%2FnQKdzT9krpwxsrQiw0yydh45cch3gDL2qe8dgcqHdpS1GdeSpON%2BkZFlP6vY%2FkuWtH8F4DEClKr1QXeIQ4VPYj58jyfcBoSgyAMMgL97jdx%2FBAaAXscn73FQ8wD8ts9HRMQ%2FpR4ypxUvZZLh%2FI1J%2F1OcGKSL1%2Fh2p6PZK5TF7zvby370M1YXqsd4xoXzwcP8dPPCJJlDMD76xSfm4UjwD%2FImRjYlhnqIeykti2nuqKzKJuPFAoV%2BFDlQNXXtpBbGjddPg5XFCC1brUNEuHXIiapMlWHwdADvq%2FBPozgyCOJCEN%2BoJzXBNk1ctcHxr2DBZfEC01Jdui9jF46mWJJS957JHQ3oVERwefgcIpWJRH3ZcaHfhcDCN9u%2BzBjqmAYsCLszALtdlfvJbXxtRTsN3P1KnSpu%2BxHyZ4rdOX3VK7kIoXOse8vDhTc8A2LdIaAVUMvoAt1JLbuBLhdKJd%2FpVraYL8phd5Wb1PT9wo%2BjAE7pe4rtgTkHzLU8Ql70CscQILZVWpDD8Moe12XoXSKb%2F%2FqcnQqIiFXnrb2tSna3zr6NWV6kUnHNBKEiiKhqtHtFSXj6s61POpjWlTy7gWmtoTHyxigQ%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIU62WQFX7A%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T113946Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=91b3179002c1c4c40d77e98368aadd9be0cf1841ce024d0b7bba684e4d2ff813) |
図表4 |
![229557-4.png](https://s3-agre-content.s3.ap-northeast-1.amazonaws.com/assets/images/seika_chart/229557-4.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Security-Token=IQoJb3JpZ2luX2VjECsaDmFwLW5vcnRoZWFzdC0xIkcwRQIhAPqlCKiamRxLtyKfyXcjrH6FPZN9b4qXmfZkK%2BSZ5WMlAiAYHPMqY7crChF7xnk3PMJrKDAluFGRrcwdY0Ops%2FkhwiqZBAjV%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F8BEAIaDDUzMjMzMTA3MjA0MSIM7VG%2FtaSAIoR6Fa3aKu0DJObNvPirEZpfYkFZTByRJ%2BlLX1g8Y%2F9S15gDPGRfrEY2mm2a24TUMn4TcAMOOo%2Fk%2BQal309owhqz2PkQXUFR0GWXpb8M84yVYf2bJoyoWDz%2FVSTWCBBoEIWlJK9v8tFLaZX5Qw1L00l9bFx0tEIpxAW6Be7Yr72hxORlSRWcealo41wpK%2BEU6NwtYBZGWt1EsUSVc2MCgsqDMGaHhrlM95gCqAjizkI2tY5dUD0dYVPcga9dvD5ROfpmQD0uGAEkNSyRPdpc4tW%2BUi7RI9BMYhB6vN%2Bo4Z%2FnQKdzT9krpwxsrQiw0yydh45cch3gDL2qe8dgcqHdpS1GdeSpON%2BkZFlP6vY%2FkuWtH8F4DEClKr1QXeIQ4VPYj58jyfcBoSgyAMMgL97jdx%2FBAaAXscn73FQ8wD8ts9HRMQ%2FpR4ypxUvZZLh%2FI1J%2F1OcGKSL1%2Fh2p6PZK5TF7zvby370M1YXqsd4xoXzwcP8dPPCJJlDMD76xSfm4UjwD%2FImRjYlhnqIeykti2nuqKzKJuPFAoV%2BFDlQNXXtpBbGjddPg5XFCC1brUNEuHXIiapMlWHwdADvq%2FBPozgyCOJCEN%2BoJzXBNk1ctcHxr2DBZfEC01Jdui9jF46mWJJS957JHQ3oVERwefgcIpWJRH3ZcaHfhcDCN9u%2BzBjqmAYsCLszALtdlfvJbXxtRTsN3P1KnSpu%2BxHyZ4rdOX3VK7kIoXOse8vDhTc8A2LdIaAVUMvoAt1JLbuBLhdKJd%2FpVraYL8phd5Wb1PT9wo%2BjAE7pe4rtgTkHzLU8Ql70CscQILZVWpDD8Moe12XoXSKb%2F%2FqcnQqIiFXnrb2tSna3zr6NWV6kUnHNBKEiiKhqtHtFSXj6s61POpjWlTy7gWmtoTHyxigQ%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAXX4LHRIU62WQFX7A%2F20240626%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T113946Z&X-Amz-SignedHeaders=host&X-Amz-Expires=1800&X-Amz-Signature=592bee3d9097bfd94619c83ad9f590aed688f08b4b2f5abed0b5db977848ac34) |
カテゴリ |
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