首页>
外文期刊>journal of fish biology
>The downstream migration of precociously mature Atlantic salmon,Salmo salarL, parr in autumn; its relation to the spawning migration of mature adult fish
【24h】
The downstream migration of precociously mature Atlantic salmon,Salmo salarL, parr in autumn; its relation to the spawning migration of mature adult fish
展开▼
机译:The downstream migration of precociously mature Atlantic salmon,Salmo salarL, parr in autumn; its relation to the spawning migration of mature adult fish
The autumn emigration of juvenile Atlantic salmon,Sulmo salurL. from the Girnock Burn, Aberdeenshire, is shown to be comprised of two components. Precociously mature males and sexually immature fish differ in their dependence on seasonal and biological cues for the release of migratory behaviour. The emigration of ripe mature male parr is shown to follow the entry of mature adult salmon to the stream; when adult fish are prevented from entering the stream, the emigration is induced by seasonal factors. Spent male parr tend not to participate in the autumn emigration. The emigration is considered to be principally an appetitive phenomenon which maximizes the number of precociously mature males attaining sexual contact with adults.
展开▼