Turn of the tern, photo by MI photographer

The Michigan DNR says that the common tern (Sterna hirundo) is a small colonial waterbird and one of four breeding species of terns in Michigan (Caspian, black, common, and Forster’s terns):

Common terns are white with a black cap, and pale gray back and wings. Their bill is red orange with a black tip. The tail is deeply forked and dark along the outer edges. Immature common terns and adults in their winter plumage have only a partial black cap. It can be distinguished from its close relative the gull by a smaller body size and longer wings. The common tern’s call is a rolling ter-arr and rapid kip-kip-kip.

Common terns are frequently seen hovering in the air over a school of fish. With a sudden plunge downward into the water, they seize fish with their bills. Sometimes they will dive entirely below the surface of the water. Terns eat small fish such as shiners, chubs, and other minnows. They will also eat crustaceans and occasionally, insects such as dragonfly nymphs.

Their winter migration takes these birds to the Atlantic coastal areas in Florida, the Caribbean, and South America. They return to their nesting sites in early spring.

Arriving on their breeding grounds in May, common terns nest in colonies of 10 to 1,000 breeding pairs. They prefer sandy, well drained areas away from mammalian predators and human disturbances. Currently, common terns are using natural and human made islands in the Great Lakes with a few nesting on inland lakes. Common terns construct their nests by creating a depression in the sand with their feet, smoothing and shaping it by sifting in it and turning their bodies. Egg laying and incubation lasts until late June or early July. Both adults take turns sitting on the nest. The adults defend the eggs and young fiercely, diving at intruders, and even striking them with their bills.

Once numbering over 6,000 breeding pairs in Michigan, common terns were found on every Great Lakes shore. Data from 1992 suggest that the population has decreased to an estimated 1,400 breeding pairs. Several factors have contributed to this decline including loss of habitat, competition with gulls, predation, and effects of contaminants. As a result of these factors, the common tern was officially listed in Michigan as a “threatened species in 1978 and has recently undergone a status assessment by the US Fish and Wildlife Service in the Great Lakes for possible listing as Federally endangered.

You can read on for more including information about the huge breeding colony on Lime Island. Also see the Common Tern Sterna hirundo from the Audobon Society andCommon Tern at All About Birds.

William caught this photo off the coast of Mackinac Island in Lake Huron. Check it out bigger and see more shots of this beautiful bird his Mackinac Island slideshow.

Many more Michigan birds on Michigan in Pictures.