Only tern in far n. Coastal islands to ME. Rare inland and on offshore migration. ID: Very similar appearance and behavior to COTE. ID should be based largely on size and shape. Sitting birds look slightly smaller, ‘neckless’ with more rounded head and very short legs. The disproportionately short neck and long tail is sometimes obvious in flight and gives a front-loaded feel. Ad br: similar to COTE with short, red bill, paler flight feathers, tail projects past wing-tip. Primaries all translucent. Nonbr/1st-s: best differentiated by shape, but paler primaries and small carpal bar create paler appearance. In flight, structural differences, paler primaries (translucent from below) with narrow well-defined black trailing edge. Juv: white secondaries that are striking in flight (compare to dark bar in COTE).