Cousin to the glossy ibis of the Southeastern U.S., the white-faced ibis winters along the Gulf Coast (from Louisiana to Texas), in valley wetlands of central and southern California and in Mexico. While some are permanent residents in these areas, most migrate through the central and western U.S. to breed on freshwater wetlands of the Northern Plains and Intermountain West.
Since wetland conditions tend to vary across the dry country of the Western U.S., these nomadic migrants are opportunistic, choosing their colonial nest sites based on the conditions that they find; for this reason, their numbers in any given area varies widely from year to year. Preferring broad, shallow wetlands with islands of vegetation, white-faced ibis nest in marsh grasses or in low trees along the shore. Both parents incubate the 3-4 eggs and participate in feeding regurgitated insects, worms, amphibians and small fish to the nestlings; the young are fledged within a month and are self sufficient by August.
Known to wander widely in late summer, small flocks of white-faced ibis turn up in the eastern U.S. on occasion but generally return to their traditional wintering grounds by mid autumn. Peak spring migrations across the Great Plains generally occur from mid April to early May and it is then that most of us encounter these attractive birds, stopping to rest and feed on shallow lakes, braided rivers or flooded fields.
