RECENT HISTORY AND STATUS OF THE EASTERN BROWN PELICAN
1994
The near catastrophic population decline of the eastern brown pelican (Pelecanus occidentalis carolinensis) in the United States during the 1960's and early 1970's has been well documented. A population of 5,000 brown pelicans in Texas declined to about 50 birds by 1964 and nesting pairs ranged from 6-53 during 1973-1980 (Texas Colonial Waterbird Society 1982). Estimates of the Louisiana population (1918-1933) ranged from 12,00085,000 (Lowery 1955, King et al. 1977a). The species was last seen nesting there in 1961 (Van Tets 1965) and was extirpated from Louisiana by 1963 (James 1963). Direct toxicity of endrin was the probable cause of the extirpation (Blus et al. 1979a). Breeding populations of eastern brown pelicans persisted in the United States only in Florida, North Carolina, and South Carolina during the 1960's and 1970's (Williams and Martin 1970, Schreiber and Risebrough 1972). Beckett reported a decline of brown pelicans in South Carolina in the early 1960's (Beckett 1966a). In South Carolina, the population declined from >5,000 breeding pairs in the early 1960's (Beckett 1966b) to 1,116 pairs in 1970 as a result of exposure to DDT which metabolized to DDE, which thins eggshells and lowers reproductive success (Blus et al. 1979b). Brown pelican numbers were low at the northern edge of the breeding range in North Carolina during the early 1960's, with '100 nests in 1 colony each year (Parnell and Soots 1976). There are no data regarding pesticide loads from North Carolina for this period. After the brown pelican was listed as endangered in the United States in 1970, an Eastern Brown Pelican Recovery Team was appointed in 1975 which produced an approved recovery plan in July 1979 (U.S. Fish and Wildl. Serv. 1980). This plan provided an organized format for progress toward the recovery goals formulated in the early 1970's (U.S. Fish and Wildl. Serv. 1980). Between the late 1960's and the early 1980's, considerable attention was directed toward population monitoring (Williams and Martin 1968, 1970; Mendenhall and Prouty 1978; Blus et al. 1979b; Wilkinson 1982), understanding the effect of organochlorine residues in brown pelican eggs on reproductive success (Blus 1982), and reintroduction of pelicans from a stable Florida population to Louisiana (McNease et al. 1984). By the late 1980's, brown pelicans had increased to record numbers in Florida, South Carolina, and North Carolina and recovered substantially in Louisiana primarily due to the reintroduction of birds from Florida (McNease et al. 1992). Based on attainment of survival and reproductive performance specified in the recovery plan, on 6 March 1985 the species was removed from the Federal Endangered Species List in Alabama, Florida, Georgia, South Carolina, North Carolina, and points north along the Atlantic Coast (U.S. Fish and
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