White Ibis

The white plumage and pink facial skin of adult American white ibises are distinctive. Adults have black wingtips that are usually only visible in flight. In non-breeding condition the long downcurved bill and long legs are bright red-orange. During the first ten days of the breeding season, the skin darkens to a deep pink on the bill and an almost purple-tinted red on the legs. It then fades to a paler pink, and the tip of the bill becomes blackish. It is difficult to determine the sex of an adult American white ibis from its external appearance, since the sexes have similar plumage. However, there is sexual dimorphism in size and proportion as males are significantly larger and heavier than females and have longer and stouter bills. This species is moderately large for an ibis but is relatively short legged, compact and bulky for a large wading bird. A study of the American white ibis in southern Florida yielded weight ranges of 872.9 to 1,261 g (1.924 to 2.780 lb) for males and 592.7 to 861.3 g (1.307 to 1.899 lb) for females, with average weights of 1,036.4 g (2.285 lb) for males and 764.5 g (1.685 lb) for females. The length of adult female and male birds ranges from 53 to 70 cm (21 to 28 in) with a 90 to 105 cm (35 to 41 in) wingspan. …

The American white ibis is most common in Florida, where over 30,000 have been counted in a single breeding colony. It also occurs throughout the Caribbean, on both coasts of Mexico (from Baja California southwards) and Central America, and as far south as Colombia and Venezuela. The non-breeding range extends further inland, reaching north to Virginia, and west to eastern Texas. The species is known to wander, and has been sighted, sometimes in small flocks, in states far out of its usual range. In North America, breeding takes place along the Atlantic coast, from southern New Jersey south to Florida and thence west along the Gulf Coast. (It nested in New Jersey for the first time in 2020, having appeared there rarely before then.) Laguna Cuyutlán is an isolated and regionally important wetland in the state of Colima on México's west coast where a breeding colony has been recorded. American white ibises are not faithful to the sites where they breed, and large breeding colonies composed of ten thousand birds or more can congregate and disband in one or two breeding seasons. Breeding populations across its range have fluctuated greatly with wholesale movement between states. Until the 1940s, the species bred only in large numbers in Florida, mostly within the Everglades. …

A field study late in the Florida nesting season revealed that on an average day, adult American white ibis spent 10.25 hours looking for food, 0.75 hours flying, 13 hours resting, roosting, and attending to their nests. Much of the time roosting is spent preening, biting and working their feathers with their long bills, as well as rubbing the oil glands on the sides of their heads on back plumage. American white ibis generally only preen themselves, not engaging in allopreening unless part of courtship behavior. Bathing often takes place before preening; ibis squat in water 5–20 cm (2.0–7.9 in) deep and flick water over themselves with each wing in succession. Hundreds of birds may bathe together around the time of courtship. The American white ibis is territorial, defending the nesting and display sites against intruders. Agonistic or threat displays include lunging forward with the bill in a horizontal posture, and standing upright and snapping the bill opposite another bird engaging in the same display. Birds also lunge and bite, often holding onto an opponent's head or wings.

Breeding and lifespan. The American white ibis pairs up in spring and breeds in huge colonies, often with other waterbird species. Nesting begins as soon as suitable foraging and nesting habitat is available. …

Native American folklore held that the bird was the last to seek shelter before a hurricane, and the first to emerge afterwards. The bird was thus a symbol for danger and optimism. For this reason, the University of Miami adopted the American white ibis as its official athletics mascot in 1926, and the yearbook was known as The Ibis from that year. The mascot was initially known as Ibis before adopting the name Sebastian in 1957. It was named after San Sebastian Hall, a residence hall on campus, which sponsored an Ibis entry in the college's homecoming celebration. Similar to the University of Miami, South Georgia Tormenta FC uses the ibis as its mascot and nickname, incorporating the bird into the team's crest.