Courtesy Kenn Kaufman
After a large range expansion northward from the 1930s through the 1970s, the Glossy Ibis breeds irregularly along the Atlantic Coast from southern Maine to Florida, across the Florida peninsula, and along the Gulf Coast into Texas. Breeding colonies are most concentrated in Florida and southwestern Louisiana. This ibis winters largely from the Carolinas south through Florida and just into Texas. Significant numbers also breed and winter through the Caribbean and most of Central America. The Glossy Ibis also occurs in southeastern Europe, most of Africa south of the Sahara, the Near East, Southeast Asia, and most of Australia east of the outback.
A legend for the range map to the right can be found here
During breeding season, the Glossy Ibis usually inhabits wooded wetlands close to the coast. Foraging birds wade in moist to submerged marshes, lagoons, and mudflats. This ibis is also found on flooded and dry fields, sewage ponds, and estuaries. Its wintering habitat appears to be similar.
Often feeding in small, close flocks, the Glossy Ibis walks slowly through marshes, feeling for prey with its long, curved bill by probing into mud and submerged vegetation. This dark ibis may also hold its bill open in shallow water, swing its bill through water, and peck items from various surfaces. The bird’s omnivorous diet includes water beetles, dragonflies, flies, earth and marine worms, leeches, mussels, clams, frogs, small snakes, small fish, and various seeds. Glossy Ibis often associate with other wading birds; some herons, like the Snowy Egret, appear to find prey disturbed by the ibis.
In North America, the breeding biology of the Glossy Ibis has not been fully studied. Glossy Ibis probably form monogamous pairs for the breeding season, and maintain bonds with mutual preening, bowing, and bill touching. Both sexes build a tight, bulky, bowl-shaped, unlined nest in a tree, shrub, or dense ground vegetation, and add material, including twigs, reeds, rushes, and course grasses, until the chicks hatch. The female lays three to four greenish-blue to dark blue eggs, which both sexes incubate for about three weeks.
The fairly helpless chicks are cared for by both sexes and are fed regurgitated food from their parents’ open bills. Different hatching times create a hierarchy based on size among the young; in clutches with four hatchlings, the smallest ibis rarely survives. Within two to three weeks, the young climb into surrounding branches, returning to the nest only for feeding. Young Glossy Ibis fledge in about four weeks, accompany their parents to foraging sites after about six weeks, and are independent in less than two months.
Migrating day or night in small flocks, often in V-shaped formations, Glossy Ibis arrive in late March through April along the Atlantic coast north of the Carolinas. After breeding, this ibis is well known for dispersing far and wide across the continent, a habit that probably led to its colonization of the Americas. Fall migrants begin to disperse in mid-July and move through America’s southern coasts and the Caribbean. A few linger in the Carolinas and Florida.