SCIENTIFIC NAME:
Mycteria americana (Linnaeus)
OTHER NAMES:
Flinthead, Ironhead, Pond Gannet, Wood Ibis (Coulter et al. 1999).
STATUS:
Possible breeder. Fairly common in late summer and early fall, but occasional to rare in spring and late fall in Inland Coastal Plain region. Occasional in spring, summer, and fall in other regions. Listed as threatened by the U.S. Fish and Wildlife Service. HIGH CONSERVATION CONCERN.
DESCRIPTION:
The largest (86-115 cm [34-45 in.]) wading bird breeding in the United States (Coulter et al. 1999). Sexes similar in appearance. Head and neck of adults featherless and dark-gray to black; body feathers and most wing coverts white, and primaries, secondaries, and tail feathers black. Grayish feathers cover head and neck of subadults. Tail short and wings long and rounded. Relatively long, stout bill; slender, blunt and decurved at tip; grayish black in adults and yellowish in juveniles. Legs dark, but feet pink (breeding) to salmon (nonbreeding). Usually silent, but on breeding grounds adults will clatter and snap bills, and infrequently will produce a low rasping fizz. Nestlings emit a high-pitched call that becomes lower-pitched with age. No recognized subspecies (Coulter et al. 1999).
DISTRIBUTION:
In North America, a resident of the southeastern United States. Occurs along the Gulf Coast from eastern Texas to Florida and along the Atlantic Coast from Florida to South Carolina. Some individuals, especially juveniles, wander north up the Mississippi Valley to Arkansas and western Tennessee, along the Atlantic Coast to North Carolina, and even occasionally as far north as Canada after breeding (AOU 1998). In Alabama, regular in summer and early fall in western Inland Coastal Plain near Tombigbee River and lakes in Hale, Marengo, and Perry Counties; at ponds near Montgomery; and at Eufaula National Wildlife Refuge (Jackson 2001b). May have bred in Macon County in 1968 (Dusi 1968).
HABITAT:
Primarily freshwater habitats, such as marshes, swamps, lagoons, ponds, and flooded fields and ditches. During extended drought, depressions in marshes and brackish wetlands have increased importance. Nesting colony sites usually freshwater and marine-estuarine forested habitats (Rogers et al. 1996). Nests primarily in upper portions of bald cypress, mangroves, or dead hardwoods over water (Coulter et al. 1999).
LIFE HISTORY AND ECOLOGY:
Colonial, usually nesting in large rookeries and feeding in flocks. Colonies range in size from a few to thousands of pairs. First breed when four years old. Time of nesting can vary with latitude. For example, in southern Florida, lay eggs in October and young fledge in February or March, whereas, in northern Florida, Georgia, and South Carolina, egg-laying occurs from March to late May, with young fledging in July and August. Stick, platform nests typically built in the upper branches of large bald cypress trees or in mangroves on islands. Three white eggs often laid (range two to five), which both parents incubate 28-32 days. Young remain in the nest for 50-55 days, and will return to nest to beg food from both parents, and to roost until 75 days old. Age of independence unknown (Coulter et al. 1999). Often use touch over vision to locate prey; with beak submerged and open, grope side-to-side while walking slowly through water. Major food items include vegetation, fish, crayfish, insects, amphibians, and reptiles (small alligators and snakes) (Coulter et al. 1999). When nesting often travel 24-64 kilometers (15-40 miles) per day to reach feeding areas (Kahl 1964).
BASIS FOR STATUS CLASSIFICATION:
U.S. population has declined precipitously in last 50 years, especially in Florida (Coulter et al. 1999). In 1960, 10,000 pairs nested in Florida, but by 1978, the number of pairs had declined to 2,520. In the Everglades of Florida, the number of pairs has declined from 2,500 in 1969 to just 100 by 1994. However, in central and northern Florida, Georgia, and South Carolina, numbers of breeding pairs have increased, although these new colonies tend to be small and may be more vulnerable to predation during dry years. Causes for decline in southern Florida include habitat degradation due to urban and agricultural expansion, and unnatural water management practices (Coulter et al. 1999). In central Florida, the loss of bald cypress swamps used for nesting has affected populations (Coulter et al. 1999). Wetlands of the Coastal Plain of Alabama provide important foraging habitat for wood storks that disperse from breeding areas in late May and during times of drought and disturbance. Full recovery in the United States will require the protection of breeding areas and important foraging sites (Coulter et al. 1999). Although breeding has not been documented in Alabama, it may breed in remote swamps of the state (Imhof 1976). Listed as endangered by the U.S. Fish and Wildlife Service in 1984. In June of 2014 wood stork status was upgraded to Threatened by the U.S. Fish and Wildlife Service.
Author:
C. Smoot Major