In the United States the Roseate Spoonbill breeds in only three states: Florida, Louisiana, and Texas. Although Roseate Spoonbills probably never were extremely abundant in Texas, they were virtually extirpated there between 1850 and 1919 because of encroaching civilization and exploitation by the millinery trade (Allen 1942). However, with the advent of laws to protect colonial nesting birds, Roseate Spoonbill numbers have gradually increased; yearly estimates of the number of breeding pairs in coastal Texas during the last two decades vary from about 1,400 to 2,500 (Texas Colonial Waterbird Society 1982, Texas Parks and Wildlife Dept. 1992). Spoonbills also winter in Texas, but usually in fewer numbers, and they may wander irregularly along water courses to more northerly counties after the breeding season (Texas Ornithological Society 1995); some birds have been sighted as far north as Amarillo in autumn (Oberholser 1974).
DISTRIBUTION: The breeding range of the Roseate Spoonbill extends for over 800 km (500 mi) along the Texas coast, from the vicinity of Port Arthur in the north to that of Port Isabel in the south. The TBBAP findings confirmed breeding (76% of total nest records) in all of Texas’s coastal counties and several inland counties. The most inland confirmed TBBAP nest locations were at Addicks Reservoir, quads H-7 and H-8 in latilong 29095, and at Lake Texana, quad F-3 in latilong 29096. The most inland probable nest locale was Somerville Lake, quad C6 in latilong 30096. Although percentages vary among recent years, census summaries indicate that about 50% of the breeding population occurs on the upper coast, 31% on the central coast, and 19% on the lower coast (Texas Colonial Waterbird Society 1982, Texas Parks and Wildlife Dept. 1992). Estimates of spoonbill nests in individual colonies in Texas are sparse, however. White et al. (1982) reported 150-200 nests on dredge-material islands in Nueces Bay at Corpus Christi during 1977-1980, and Oberholser (1974) referred to five large active colonies in the central coastal area in 1941 but did not mention nest estimates.
SEASONAL OCCURRENCE: Adult spoonbills in full breeding plumage begin congregating at colony sites around mid-March each year (White et al. 1982). Birds are not paired at this time and they loaf in large groups in the vicinity of the nesting area. By mid-April, some pairing has occurred and rudimentary nests are present by late April. Egg laying usually begins during early to mid-May. Data from marked eggs in 29 nests confirmed that laying occurred at the rate of one egg every other day; the time in the nest until hatching is 23 days for the first egg and 22 days for the others (White et al. 1982). Incubation begins the day after the first egg is laid, so the incubation period for each egg is 22 days. On the lower coast, earliest dates for nests with young documented by the TBBAP were 29 May, 4 June, and 6 June. Young spoonbills fledge in early July at about six weeks of age and by early August adults and young begin to disperse from the nesting area.
BREEDING HABITAT: Roseate Spoonbills in Texas nest in multi-species colonies in sloughs, marshes, fresh water and brackish lakes, and salt water bays and lagoons (Allen 1942, Oberholser 1974, White et al. 1982). They are among the first to congregate at the colony sites, usually selecting nest sites in or atop low woody vegetation (rarely on the ground). In Nueces Bay, spoonbills nested only on dredge-material islands and constructed their nests of plant material available there or on the nearby shoreline (White et al. 1982). The nest base consisted of large dead twigs of groundsel tree (Baccharis halimifolia), border paloverde (Cercidium macrum), and Jerusalem-thorn (Parkinsonia aculeata) loosely fitted together to form a crude platform. Upon this platform, live and dead stems of sea ox-eye (Borrichia frutescens), groundsel tree, and grasses were intertwined into a coarse lining about 5 cm (2 in) deep. The activities of the birds on the nest eventually formed a wide, shallow depression in which the eggs were laid. Completed nests averaged 57 cm (22 in) wide and 11 cm (4 in) deep. Nest height above ground averaged 24 cm (9 in) atop low vegetation and 71 cm (28 in) in small trees and shrubs. Spoonbills never built nests on platforms remaining from the previous year.
STATUS: According to Allen (1942), Audubon saw thousands of Roseate Spoonbills along the Texas coast in 1837. By 1920, a survey party reported only 179 non-breeding birds in June on the central and lower coast. However, egg collectors took three clutches in 1921, 1923, and 1924 in Victoria and Refugio counties (Welder Wildlife Foundation Egg Collection, pers. obs.). With the decline in plume hunting, spoonbill numbers quickly rebounded. Over 5,000 spoonbills were present on the Texas coast in 1941 (Allen 1942) and the Cooperative Fish-eating Bird Survey reported 4,470 individuals in 1968 (Oberholser 1974). Surveys for the Texas coast over a recent 20-year period (1973-1992) suggest that spoonbill numbers during summer range from about 1,400 to 2,500 breeding pairs (2,800 and 5,000 individuals, respectively). Trend data from the Breeding Bird Survey (Sauer et al. 1997, accessed on 7/13/98) show a slight increase (+1.5%) in spoonbill numbers for the entire Texas coast, but this trend may reflect normal population fluctuations.
Despite high levels of DDE in some Roseate Spoonbills at Nueces Bay, reproduction (fledglings/eggs laid) appeared to be good, averaging about 50% (White et al. 1982). Because of a paucity of comparable reproductive data on this species, it is difficult to assess whether this figure is sufficient to maintain the population. Since present numbers appear to be holding steady at about 2300 breeding pairs (Texas Parks and Wildlife Dept. 1992), nest success probably is adequate and the population is in no immediate danger of serious decline.
Text by Donald H. White (ca. 1998)
Allen, R. P. 1942. The Roseate Spoonbill. National Audubon Society, Res. Rep. No. 2., New York.
Oberholser, H. C. 1974. The bird life of Texas. University of Texas Press, Austin.
Sauer, J. R., J. E. Hines, G. Gough, I. Thomas, and B. G. Peterjohn. 1997. The North American Breeding Bird Survey Results and Analysis. Version 96.4. Patuxent Wildlife Research Center, Laurel, Maryland.
Texas Colonial Waterbird Society. 1982. An atlas and census of Texas waterbird colonies, 1973-1980. Texas Colonial Waterbird Society, Caesar Kleberg Wildl. Res. Inst., Texas A&I University, Kingsville, Texas.
Texas Ornithological Society. 1997. Checklist of the birds of Texas, 3rd ed.n. Capitol Printing, Inc., Austin, Texas.
Texas Parks Wildl. Dept.. 1992. Texas Colonial Waterbird Census Summaries, 1981-1992. Federal Aide Project Nos. W-103-R-10, W-103-R-12, W-103-R-14, W-103-R-16, W-103-R-17, W-103-R-18, W-125-R-1, W-125-R-3, Austin.
White, D. H., C. A. Mitchell, and E. Cromartie. 1982. Nesting ecology of Roseate Spoonbills at Nueces Bay, Texas. Auk 99: 275-284.