WOOD STORK  Mycteria americanaMycteria americana

The Wood Stork is federally classified as an endangered species and is listed as a threatened species in Texas. Wood Storks have not been reported to nest in Texas since 1960 and the only known breeding colonies north of Mexico occur in Florida (primarily in the Everglades) and coastal Georgia, South Carolina, and, recently (2005-2006), North Carolina (Bill Brooks, [USFWS] pers. comm.). However, there is no evidence colonies outside Florida, at any time prior to 1970, formed on a regular basis or contained large numbers of birds (USFWS 1996).

Wood Storks breeding in the southeastern United States exhibit lengthy inter- .and  intra-regional movements in response to resource availability (Bryan et al. 2007). One type of movement, post-breeding dispersal, has resulted in storks from this southeastern population temporarily moving into the Gulf Coast states of Alabama and eastern Mississippi. Concurrently, other Wood Storks, presumably originating from breeding colonies in Mexico and/or Central America (Coulter et al. 1999), are frequently observed in large numbers in the lower Mississippi River Valley, Louisiana, and Texas during the late-summer/fall months. The proximity of dispersing storks from the two regions might result in population mixing.

Storks from eastern Mexico may move into Texas, Louisiana, and Arkansas and storks from western Mexico may move into California and Arizona (Matthews and Moseley 1990, Hancock et al. 1992). The endangered status of this species is currently linked with the breeding population in Florida; thus, if these post-breeding wandering birds are from Mexico or Central America, they are not afforded protection via the U. S. Endangered Species Act.

Understanding the origins, migratory routes, and chronology of Wood Stork populations is one of the last remaining migratory bird mysteries in North America. Currently, modern satellite telemetry is being applied to this question. Public relations and public outreach activities via an interactive computer web-site program are being implemented. Also, because of the physical uniqueness of this bird, its ties to wetlands, and the high visibility potential of this research, excellent opportunity is being provided for one or more corporate partners to establish a notable environmental involvement (USFWS 1996).

DISTRIBUTION: Wood Storks are seen mainly east of a line from Dallas to San Antonio to Zapata; but during fall migration, as many as 5000 have been reported in a single day flying over the central and upper coasts (Lockwood and Freeman 2004).

Spring/fall movements of two birds, captured in western Mississippi and fitted with transmitters for satellite tracking, have been traced   southward   and  northward along  the   coastal area of Texas (Bryan et al. 2007).

One presumably nested in the eastern state of Veracruz, Mexico, west of the Usumacinta River delta; and, the other presumably nested near the Pacific coast of Guatemala.

SEASONAL OCCURRENCE: Wood Storks are usually seen from late May to mid-October with extreme dates from April 3 to November 30. These storks appear irregularly, and are uncommon to formerly abundant on the upper and central coasts and scarce to formerly common on the lower coast and Rio Grande delta. This species wanders widely inland from July to September, especially in eastern Texas. In winter individuals and small flocks are seen rarely along the coast (Oberholser 1974).

BREEDING HABITAT.  Wood Storks nest in swamps or on islands surrounded by relatively broad expanses of open water. Their nests are typically constructed in short (1 m, [3 ft]) shrubs, especially red mangroves (Rhizophora mangle), to medium or tall trees (31 m, [100 ft]), especially bald cypress (Taxodium disticum; USFWS 1996). In these habitats, they nest within multi-species colonies composed of Anhingas (Anhinga anhinga), Great Blue Herons (Ardea herodias), Great Egrets (A. alba), Snowy Egrets (Egretta thula), Little Blue Herons (E. caerulea), Cattle Egrets (Bubulcus ibis), Black-crowned Night-Herons (Nycticorax nycticorax), White Ibises (Eudocimus albus) and Roseate Spoonbills (Platalea ajaja).

STATUS: In Texas, there are only 3 known nesting records: 1930 in Chambers County, Elm Grove; 1960 in southwestern Jefferson County, Johnny Pipkin’s Big Hill Ranch (about. 50 breeding adults with nests, eggs, and chicks);  and, year unknown in Harris County, San Jacinto River (Oberholser 1974). On June 1, 1998, a pair of adult Wood Storks was observed in a heronry at Birds’ Roost on Caddo Lake in northeast Texas (e-mail note from Gregory McKenna, a graduate student at Louisiana State University to Jim Neal, Wildlife Biologist of the U.S. Fish and Wildlife Service in Nacogdoches, Texas). That date is early for post-breeding dispersal; but, no nest was observed.

Stick-carrying has been observed twice: on the lower coast at Lake Corpus Christi State Park on April 21, 1990 (Lasley and Sexton 1990); and, at Caddo Lake in northeast Texas one bird within a group of 13 was seen carrying a stick  on July 1, 1996 (Lasley et al. 1996).

Text by Raymond C. Telfair II (2007)

Texas Breeding Bird Atlas map

Literature cited.

Bryan, A. L., Jr., W. B. Brooks, J. D. Taylor, D. M. Richardson. C. W. Jeske, and I. L. Brisbin, Jr. 2007. Satellite tracking large-scale movements of Wood Storks captured in the Gulf Coast Region. Waterbirds 30: In press.

Coulter, M. C., J. A. Rodgers, J. C. Ogden, and F. C. Depkin. 1999. Wood Stork (Mycteria americana). In The Birds of North America, No. 409 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Hancock, J. A., J. A. Kushlan, and M. P. Kahl. 1992. Storks, ibises, and spoonbills of the world. Academic Press, New York.

Lasley, G. W. and C. Sexton. 1990. Texas region (spring season). Am. Birds 44: 458-465.

Lasley, G. W., C. Sexton, M. Lockwood, and W. Sekula. 1996. Texas region (summer season). Field Notes 50: 968-973.

Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.

Matthews, J. R. and C. J. Moseley (editors). 1990. The official World Wildlife Fund guide to endangered species of North America. Volume 2. Birds, reptiles, amphibians, fishes, mussels, crustaceans, snails, insects, and arachnids.Beacham Publications, Inc., Washington, D.C.

Oberholser, H. C. 1974. The bird life of Texas, University of Texas Press, Austin.

U.S. Fish and Wildlife Service. 1996. Revised recovery plan for the U.S. breeding population of Wood Storks. U.S. Fish and Wildlife Service, Atlanta, GA.

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