Based on band-recovery data, the breeding range of the American White Pelican is divided into two distinct east-west segments separated by the Continental Divide (Anderson and Anderson 2005). Most breeding colonies are north of 40º N latitude. However, there are three isolated southern breeding populations within the eastern segment: 1) the Texas breeding population (200-500 pairs in the Laguna Madre) nests most years; and, is well-isolated from the nearest northern breeding population in northern Colorado; 2) a small (10 pairs) sporadically nesting population at Laguna de Satiaguillo, Durango, Mexico; and 3) 100-500 pairs of an infrequently nesting population in the Laguna Madre de Tamaulipas, Tamaulipas, Mexico (Chapman 1988). According to Sloan (1982), the Texas breeding population may be the only non-migratory population in North America. Chapman (1988) hypothesized that this group may have originated from a few birds that did not migrate north to their traditional breeding site. However, one banded and four color-marked birds from a 5-year study in Texas were observed in late summer/fall in northern breeding grounds (the banded bird at Lake Winnipeg, Manitoba, Canada in Sept. 1983 and the color-marked birds at Agassiz National Wildlife Refuge, Minnesota, July 20, 1984 (Mabie 1982-1984).
Four color-marked birds were observed in Laguna Machona, Tabasco, Mexico one color-marked bird was observed in Charleston, South Carolina August 21, 1980; 120 sightings/band recoveries occurred within the entire coastal region of Texas between August 3 and December 21 (1979-1984); and, a single bird was observed just inland of the central coast in Bee County, August 8, 1980. Most (107, 89.2%) of Texas observations and band recoveries occurred on the central coast from San Patricio to Kenedy counties.
DISTRIBUTION: As migrants and summering non-breeding birds, American White Pelicans are found statewide, both coastal and inland (marine, estuaries, lagoons, reservoirs). Breeding occurs only on the central and lower Texas coast. Oberholser (1974) lists scattered breeding records for islands in Mesquite Bay (Calhoun-Aransas county line), Nueces, and Cameron counties, with South Bird Island, Kleberg County as the only regular recent colony. However, almost all breeding records since 1907 have occurred in the upper portion of the Laguna Madre (Chapman 1988). Nesting has occurred on four natural islands (Ward Island in Oso Bay and a small island in West Nueces Bay, Nueces County. North and South Birds Islands, Kleberg County; East Potrero Grande, Kenedy County and on two dredge material (spoil) islands, numbers 55 and 81. An historical record and chronology of nesting from 1907-1987 was reported by Chapman (1988). From 1926 until 1980, nesting occurred on South Bird Island and the population remained relatively stable.
Beginning in 1976, nests were also constructed on Spoil Island 5; in 1981, also on East Potrero Grande; and, in 1982, also on Spoil Island 81 and in West Nueces Bay. Since 1983, all nesting has occurred on Spoil Island 81 which is isolated and located within the Padre Island National Seashore where the pelicans receive protection (Chapman 1988, Texas Colonial Waterbird Database 2007).
SEASONAL OCCURRENCE: Eggs have been recorded in Texas from March 25-July 14 (Oberholser 1974, Chaney et al. 1978, but, most egg-laying is probably in March/April. Dependent young may be present into August (Blacklock 1978, Chaney et al. 1978). Fall migration occurs from late August to mid- November and spring migration occurs from early April to early June. In summer, statewide, non-breeding birds are scarce to fairly common (Oberholser 1974; Lockwood and Freeman 2004). Migratory flocks (some as large as 4,000-11,000) are uncommon to common over the eastern half of the state, decidedly less common in the western half. Winter residents are common in the southern half of the state, especially along the coast and on inland reservoirs in the northern half and Trans-Pecos region (Lockwood and Freeman 2004)
BREEDING HABITAT. Nesting sites include spoil islands: bare ground along the periphery of great leadtrees (Leucaena leucocephala; Chaney et al. 1978). On North Bird Island breeding occurs on halophytic grasses and subshrubs to 0.5 m (1.6 ft), annuals and shrubs to 1 m (3.3 ft), and scattered prickly-pear (Opuntia sp.) to 1 m (3.3 ft). On South Bird Island, nests were placed on loose sand and shell fragments, halophytic grass and subshrubs to 0.5 m (1.6 ft), prickly-pear to 1.0 m (3.3 ft) and yucca (Yucca sp.) to 2.5 m (8.2 ft). On Spoil Island 81, pelicans nest on bare sand, dense baccharis (Baccharis sp.) on higher parts, and dense bushy sea ox-eye (Borrichia frutescens (Texas Colonial Waterbird Society 1982).
STATUS: The general trend of populations in North America has been distinctly upward since the early 1970s when colonies were inadequately protected from disturbance, to which they are extremely sensitive, and, the birds were subjected to reproductive impairment from pesticides (Johnsgard 1993). During the 1970s, as few as 129 pairs were censused along the Texas coast (Texas Colonial Waterbird Society 1982). Generally, the annual breeding population has varied from 200-500 pairs from 1907 to the late 1980s (Chapman 1988). Between 1973-2000, the Texas breeding population has had a very significant increasing trend of about 2.5% annually (McFarlane 2002).
Text by Raymond C. Telfair II (2007)
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Blacklock, G. W. 1978. Birds of Padre and Mustang Islands and adjacent waters. Annotated checklist (unpubl. ms).
Chaney, A. H., B. R. Chapman, J. P. Karges, D. A. Nelson, R. R. Schmidt, and L. C. Thebeau. 1978. Use of dredged material islands by colonial seabirds and wading birds in Texas. U.S. Army Engineer Waterways Exper. Stn., Vicksburg, MS. Tech. Rept. D-78-8.
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Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.
Mabie, D. W. 1982-1984. White Pelican study. Texas Parks and Wildl. Dept. Job 43, Fed. Aid Proj. No. W-103-R-12, 13, 14.
McFarlane, R. W. 2002. Texas colonial waterbird trends (powerpoint resentation). http://www.fws.gov/texascoastalprogram/TCWC.htm.
Oberholser, H. C. 1974. The bird life of Texas, University of Texas Press, Austin.
Sloan, N. F. 1982. Status of breeding colonies of White Pelicans in the United States through 1979. Am. Birds 36: 250-254.
Texas Colonial Waterbird Database. 2007. Texas colonial waterbird database (1973-2003). http://www.fws.gov/texascoastalprogram/TCWC.htm.
Texas Colonial Waterbird Society. 1982. An atlas and census of Texas waterbird colonies, 1973-1980. Caesar Kleberg Wildl. Res. Inst., Texas A&I Univ., Kingsville.