Each year, field workers travel from the southwestern United States to eastern Washington to harvest apples. This movement is an example of __________.

The workers travel to eastern Washington for apple harvest each year, then return elsewhere afterward. This is periodic movement: a repeated, temporary migration tied to a seasonal activity. Permanent migration would mean settling in a new place, while transhumance is the seasonal movement of livestock and herders; commuting is regular travel between home and work.

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