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Roseate Spoonbill

Order: Ciconiiformes
Family: Threskiornithidae
Genus/Species: Ajaia ajaja

Description
The Roseate Spoonbill, a large wading bird with pink plumage and a distinctive spatulate bill, is one of the most striking birds found in North America. They stand 85 cm tall and have a 1.3 m wingspan. The bare skin of the adult's head has a greenish tinge with a darker black band around the base of the skull. The eyes and legs are red. The feathers of the neck, chest, and upper back are white. The upper wing coverts are red, the tail feathers are orange-pink, and the rest of the body and wing feathers are pale pink. The unique pale grey bill is long, flattened and spoonlike in appearance. Immature birds are paler in color and have feathered heads.

Distribution and Habitat
Breeding in the United States is restricted to coastal Texas, southwestern Louisiana, and southern Florida. Their breeding range extends south from Florida through the Greater Antilles to Argentina and Chile. They inhabit marshes, swamps, ponds, and rivers within their range, feeding in both fresh and saltwater wetlands. Highly gregarious, Roseate Spoonbills breed and travel in flocks.

Diet
Spoonbills consume a varied diet of small fish, amphibians, aquatic invertebrates, and some plant material. They feed in the early morning and evening hours by wading through shallow water with their bills partially submerged. As a Roseate Spoonbill walks it swings its head back and forth in a sideways motion. When the bird feels a prey item it snaps its bill closed, pulls the prey out of the water, and swallows it.

Reproduction
Most spoonbills do not breed until they enter their third year. Courtship displays include ritualized exchanges of nest material, dancing and bill clapping. Copulation occurs at the nest site. The female builds a strong cup nest of sticks and twigs utilizing materials brought to her by the male. The Florida population prefers to nest in red and black mangroves, sometimes in conjunction with Wood Storks and herons. The Texas and Louisiana populations often nest on the ground in off-shore island mixed colonies with gulls, terns, and herons.

The female lays three cream colored eggs marked with darker brown spots. Incubation takes 22 to 24 days, with both parents sharing the incubation duties. The newly hatched chick appears to be mostly pink skin with a sparse covering of white down and an orange bill, legs and feet. The parents feed the chick by dribbling regurgitated material into their upturned bills. At one month of age the partially feathered chick begins to exercise by clambering about in the branches or foliage surrounding the nest. They fledge at six weeks of age.

Conservation
The lovely pink primaries of the Roseate Spoonbill were highly prized for use in the construction of ladies' fans at the turn of the century. This made Spoonbills one of the favorite targets of the professional plume hunters that decimated so many species of wading birds. By the 1930's the once thriving Florida population had dropped to an historic low of 30 to 40 breeding pairs, nesting only in a few small colonies on the keys of Florida Bay. Once they gained full legal protection from hunting the species began to rebound.

Now over a thousand pairs nest in Florida. The ground nesting colonies in Texas and Louisiana are extremely vulnerable to any predator that can make its way to their off shore islands. Entire colonies have been known to shift locations. As suitable sites become increasingly scarce due to coastal development birds may be forced to continue to nest in vulnerable sites. Some populations show high levels of pesticide levels in their eggs but they do not appear to be significantly impaired by egg shell thinning at this time.

References
Ehrlich, P.R., Dobkin, D.S. and D. Wheye. 1988. The Birder's Handbook. Simon and Schuster, New York.

Farrand, J. Jr. ed. 1983. The Audubon Society Master Guide to Birding Vol. 1. Alfred A. Knopf, Inc. New York.

Netherton, J. 1994. At the Water's Edge: Wading Birds of North America. Voyageur Press, Stillwater, MN.

Photo by Jessie Cohen, NZP


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