Noun migrator has 2 senses

• migrator(n = noun.person) migrant - traveler who moves from one region or country to another; Array
is a kind of traveler, traveller
has particulars: departer, goer, leaver, emigrant, emigre, emigree, outgoer, evacuee, immigrant, rusher, colonist, settler
Derived form verb migrate₁

• migrator(n = noun.animal) Array - an animal (especially birds and fish) that travels between different habitats at particular times of the year; Array
is a kind of animal, animate being, beast, brute, creature, fauna
Derived form verb migrate₁