migrator vs traveller

migrator and traveller both are nouns.

Word	Noun	Adjective	Verb	Adverb
migrator	Yes	No	No	No
traveller	Yes	No	No	No

As nouns, traveller is a hypernym of migrator; that is, traveller is a word with a broader meaning than migrator:

Other hypernyms of migrator include traveler.

migrator (noun)	traveller (noun)
an animal (especially birds and fish) that travels between different habitats at particular times of the year	a person who changes location
traveler who moves from one region or country to another