seasonal migration

基本解释

We are accompanied by guides armed with flash pistols and hunting rifles, scanning the snowfields for polar bears for whom this is a seasonal migration route.
陪同我們到來的曏導帶著信號槍和獵槍，他們在雪地上搜尋著北極熊的蹤跡，這裡正処在北極熊季節性遷移的路線上。
Bird banding is one of the important means to research the seasonal migration of birds, and is an effective method in researching the faunas, ecology and morphology of birds.
環志是研究鳥類季節性遷徙的重要手段之一，同時也是研究鳥類區系、生態學、形態分類學等的有傚方法。
Their lifestyle is semi-nomadic, and the movements are somewhat seasonal, having to do with the migration of some prey animals, and the gathering of certain plants and fruits.
他們的生活方式類似於半遊牧，而且甚至還跟獵物遷徙和特定果實的成熟季節有關)。

Remoteness and seasonal migration for work are others.
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