Winter migration

…In the Northern Hemisphere, migration generally goes from north to south, and spawning grounds are often located at the southern limit of the distribution range. For this reason, it is often difficult to distinguish between wintering migrations to avoid the drop in water temperature and spawning migrations. Feeding migrations go in the opposite direction, from south to north. …

*Some of the terms mentioned in "winter migration" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…また北半球では北から南に向かうのが一般で，分布範囲の南限に産卵場のあることが多い。このため，水温の低下をさける越冬回遊と産卵回遊とは区別しにくい場合が多い。索餌回遊は逆に南から北へ向かう。…

※「越冬回遊」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報