Many thanks October donors. November donations open; our costs are higher during this hosting transition. - Donate here
From Citizendium, the Citizens' Compendium
This article contains just a definition and optionally other subpages (click here to check), but no metadata. if you want to expand this into a full article.
Migration (ecology) : The usually seasonal displacement observed in the life cycles of many animal species, e.g. whales, fish, birds, and insects.