Its flight is bouyant and erratic. They are often observed hovering above marshes. When feeding, it circles low over foraging areas with slow, shallow wingbeats and its bill pointed down. The bird may then hover briefly before a sudden drop or swoop to the surface, next it dips its bill into the water or picks an insect off vegetation. These birds have even been recorded chasing minnows cast by fishermen.
Parents are very solicitous when their home is approached.
They dart about screaming and make angry swoops at the head of the intruder, often striking hard with their bills. The young remain well to the south, not migrating north to any considerable extent until fully mature. The preferred summer habitats of the black tern are inland marshes and sloughs with fairly dense cattail or other marsh vegetation and pockets of open water. These wetlands are often shallow in nature. Negative Humans approaching the nest of a black tern may come with a serious headache because these birds have been known to attack humans that come too close.