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
Numerology games, players may employ "lucky numbers" to find what they think will help them. There is no evidence that any such "numerological strategy" yields a better outcome than pure chance, but the methods are sometimes encouraged, e.g. by casino owners. Numerology is a popular plot device in fiction. Sometimes it is a casual element used for comic effect, such as in an episode titled "The Séance" of the 1950s TV sitcom "I Love Lucy", where Lucy dabbles in numerology. Sometimes it is a central motif of the storyline, such as the movie "π", in which the protagonist meets a numerologist