Distribution

Figure 1. Normal breeding and nonbreeding range of the White Ibis.

The Americas

Breeding Range

Nomadic tendencies and shifting populations year to year make accurate depiction of breeding range a moving target. In general, however, primarily coastal from Virginia through Louisiana and Texas, with centers of abundance in the Carolinas, Florida, Louisiana and Texas; also inland from the coast in S. Carolina through Florida; local in the Caribbean, and along both coasts of Mexico and Central America south to coastal n. South America; rare and local along Pacific coast in Ecuador and Peru (Fig. 1).

For details on distribution of US populations since 2000, see Demography and Populations: population status.

In Mexico and n. Central America, sea level to 150 m from Baja California Sur, Sonora and Tamaulipas south along both coasts to Chiapas (possibly El Salvador) and n. Honduras (Bay Islands) (Howell and Webb 1995). In Costa Rica, locally common resident in lowlands of both slopes, with centers of abundance in Golfo de Nicoya, Tempisque basin, and Rio Tempisque; occasionally common in Rio Frio region and locally farther south (Stiles and Skutch 1989). In Panama, primarily Pacific slope with nesting recorded on islands in Panama Bay and on Azuero Peninsula in Herrera and Los Santos (Ridgely and Gwynne 1989). Common breeder on Cuba, especially coastal regions (Isle of Pines; northern cays; Garrido and Kirkconnell 2000), and on Hispaniola, but rare and local on Jamaica and not known to breed elsewhere on Caribbean islands (e.g., Bahamas, Puerto Rico, Windward Isles) (Raffaele et al. 1998), nor on Trinidad or Tobago (ffrench 1991).

In Colombia, possible breeder but no clear records (Hilty and Brown 1986). Known to breed in Venezuela along north coast, but rare; local inland in south (llanos), where mixed colonies (Scarlet and White, and hybrids) are found, with Scarlets predominating (Hilty 2003). Along Pacific coast of n. South America, in Ecuador, rare and local breeder: "... Numbers … highest in the Ri'o Guayas estuary ... where the species is resident and almost certainly breeds. .. small nesting colony also seen in mangroves near Puerto Pitahaya in El Oro in Apr 1993…. Presumably the species breeds locally in Manabi' and Esmeraldas as well, as there is no evidence of any surge in numbers when migrants would be expected to be arriving from the north" (Ridgely and Greenfield 2001). In Peru, may breed in small numbers along the northwest coast, but confirmation lacking (T. Schulenberg).

Through n. and e. South America, Scarlet Ibis predominates. However, scarlet birds often documented in the range of white birds and almost certainly were natural visitors to Florida historically (Simpson 1988). Some Scarlet Ibis introduced into Florida in the 1950s, others have escaped from captivity more recently. Today, individual scarlet birds nest in the wild in Florida, including Florida Bay (1 May 1980, Kushlan and Frohring unpubl. data). Pink hybrid individuals also nest in the wild in Florida and occur occasionally as far north as coastal S. Carolina (Belser 1989).

Winter Range

In winter, coastal Carolinas south over rest of breeding range. Normal non-breeding range is wider because of post-breeding dispersal, often northward in late summer and fall – e.g., regular as far north as Delaware (Hess et al. 2000) and se. NY State (Long I., Levine 1998; Fig. 1).

Historical Changes In Distribution

Extension of breeding range north of Georgia occurred mainly in 20th century (Wayne 1922, Sprunt 1944, Stephens 1950, Frohring and Beck 1978). Large increases in population 1980-2005 in Texas, Louisiana, South Carolina, and N. Carolina, decreases in s. Florida (Frederick et al. 1996; see Demography and Populations: status and trends). Northward dispersal post-breeding accelerated in 1970’s and 80’s, perhaps with expansion of breeding range into Virginia during that period (e.g., Delaware: Hess et al. 2000; NY State: Levine 1998).