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Spoonbills are named for their distinctive spatulate bill. |
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Photo © Peter Wallack |
Roseate spoonbills are named for their pink plumage and their distinctive, long spoon-shaped bill. Of the six species of spoonbills, no other spoonbill is so brightly colored.
The roseate spoonbill's plumage is pink with red highlights and orange tail feathers. Like the flamingo, the roseate spoonbill owes much of its pink coloring to pigments imparted by crustaceans it eats. Adult male and female roseate spoonbills are quite similar in appearance, though males are somewhat larger with longer bills. The average adult is 26 to 31 inches tall, with a wingspan of about 50 inches across, and weighs about 3 pounds.
The distinctive spatulate shape of its bill sets the roseate spoonbill apart from other wading birds such as herons and egrets, which use swordlike beaks to stab their prey, and from flamingos, which use their beaks as scoops. Roseate spoonbills hunt by touch instead of sight, a crucial adaptation for a bird that feeds in muddy or vegetation-clogged waters.
To feed, spoonbills wade through water no deeper than knee level, with their bill immersed, mandibles slightly open, sweeping their bill in rapid arcs from side to side to create swirling currents like mini-whirlpools that pull up small prey from the muddy bottom. Sensitive touch receptors along the bill's length detect vibrations and signal the bill to close quickly on the prey swept inside the spoon. Papillae then help move the food back to the throat. This unusual and specialized feeding style is known as "head-swinging."
The roseate spoonbill is the only spoonbill species that lives in the Western Hemisphere and can be found on the coasts of Texas, Louisiana, and southern Florida, as well as in the tropics and in Central and South America. These birds thrive in marshes, tidal ponds, rivers, lagoons and mangrove swamps, where they can find the dense concentrations of prey they need in order to feed effectively. Those that live in the tropics usually don't migrate, but those that live in the southern United States will migrate in response to changing food availability and rainfall patterns.
Roseate spoonbills are social birds, spending much of their time with other spoonbills and water birds, and nesting in colonies alongside ibises, storks, cormorants, herons, and egrets. Spoonbills usually feed in groups, often near herons or other waders. Since spoonbills feed with their heads down, they rely on these vigilant neighbors to provide warning of danger -- otherwise, one of the spoonbills will often serve as sentry.
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The Roseate Spoonbill's plumage brightens during breeding season. |
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Photo © Peter Wallack |
Roseate spoonbills are serially monogamous, keeping the same mate for an entire breeding season but not for life. Their feather colors brighten in breeding season and males try to impress females with ritual courtship displays and by demonstrating their talent in collecting sticks and other suitable nesting material. Once the female has selected a male, she will then use the material he gathers to build a large, deep nest in the lower branches of a tree close to water.
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Spoonbills fly with their neck and legs stretched out. Photo © Peter Wallack |
The female spoonbill lays between one and four white, speckled eggs and the parents alternate sitting on the clutch. The eggs hatch after 22 to 24 days of incubation. Both parents feed the chicks by regurgitation. The young are able to fly by the time they are 4 to 5 weeks old, but they remain near their parents until they are about 8 weeks old and have learned enough to live on their own.
Roseate spoonbills were driven to the brink of extinction by hunters supplying the millinery trade in the late 19th century. The plumes of other wading birds such as snowy and great white egrets were more desirable for use in decorating ladies' hats than those of spoonbills, whose feathers tend to quickly lose their pink color. Even so, spoonbills wings were used as fans. And since spoonbills tend to nest in colonies with egrets and herons and would abandon their nests when disturbed, their population suffered severely as a result of plume hunters. Only a few dozen breeding pairs of roseate spoonbills remained in North American in the early 1900s. Spoonbills received legal protection from hunting in the 1940s and have responded well to extensive restoration efforts.
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Roseate Spoonbills have recovered from near extinction. |
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Photo Texas Parks & Wildlife Dept |
Although they are no longer listed as an endangered species, roseate spoonbills are extremely sensitive to environmental change, and can thus provide insight into the overall health of their habitat. Their populations decline when faced with the broad use of pesticides to control mosquitoes and the draining and pollution of their wetland habitats. Many national wildlife refuges such as J.N. "Ding" Darling NWR in Florida and Anahuac NWR in Texas provide protected habitat for these and other sensitive wading birds.
