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
Elegant tern a characteristic loud grating noise like a Sandwich tern. This bird could be confused with the royal tern or Forster's tern, but the royal tern is larger and thicker-billed and shows more white on the forehead in winter. Out of range, it can also be easily confused with the lesser crested tern. See also orange-billed tern, and the external link below. This species is marginally paler above than the lesser crested tern with a white (not grey) rump, with a slightly longer, more slender bill with a different curve. The black of the crest that comes down from the crown