Terns are gull like but slimmer, with pointed wings and beaks. In breeding plumage the black tern has a black head and underparts and gray wings. In Michigan they prefer open or swampy marsh habitat. Nests may be on floating masses of vegetation, or wood debris, or on muskrat houses or small patches of solid ground. They will use man made artificial nesting platforms. (Write to the DNR Nongame Wildlife Fund for nesting platform plans.) The downy young usually stay on the nest for two weeks, but will leave quickly if disturbed, thus human intrusion near nests with very young nestlings can be a serious problem. Black terns feed on insects and small fish, usual ly picking food from the surface rather than diving like other terns. Their numbers have fallen seriously in recent years.