Medium-sized tern with thick black bill. Very pale overall with black cap in breeding plumage. Legs black. Nonbreeding plumage shows dark cheek patch. Found in marshier habitats than most other terns, in the Americas usually near the coast but not on the ocean (though also occasionally seen on beaches and mudflats); in Europe and Asia can also be found in wetlands well away from the coast. Rarely seen in flocks with other terns; often single or in pairs. Feeds on invertebrates and crabs in mud and marshes; often patrols the edges of ponds but does not grab fish from the water like other terns.