The common tern migrates from as far south as Brazil to as far north as Nova Scotia, often returning to the same site to breed. Pairs will commonly mate for life, and the two will share responsibilities including incubation, feeding and guarding of the nest.
“The dedication of these terns to their nests is inspiring, and not less so because of their unconscious dependence on the weather. They pivot on its power and forbearance. A tern sitting on its nest centers the year.”
–John Hay, The Bird of Light