Tern make up the clutch. Most species feed on fish caught by diving from flight, but the marsh terns are insect-eaters, and some large terns will supplement their diet with small land vertebrates. Many terns are long-distance migrants, and the Arctic tern may see more daylight in a year than any other animal. Terns are long-lived birds and are relatively free from natural predators and parasites; most species are declining in numbers due directly or indirectly to human activities, including habitat loss, pollution, disturbance, and predation by introduced mammals. The Chinese crested tern is in a critical situation and three other
Miller Tern brakes and an optional tail-mounted drag chute. The cantilever wing uses a Wortmann 61 series airfoil. The basic Tern has a wingspan that gives a glide ratio of 34:1 at , while the longer span Tern II, with its wingspan, has a glide ratio several points higher. In March 2011 there were 14 Terns on the Federal Aviation Administration register, including 4 Tern IIs and one Tern 17M. All Terns are registered in the USA as "Experimental - Amateur-built" In March 2011 there were two Terns registered with Transport Canada, both amateur-builts. Miller Tern The Miller Tern is an American