EASTERN BROWN PELICAN Pelecanus occidentalis carolinensis (Gmelin) 



Order: PELECANIFORMES Family: PELECANIDAE 



Distinguishing characteristics : A large dark gray-brown water bird with white about the 

 head and neck in the adults. Immatures are gray -brown above and on neck, with white 

 underparts . Flies with its head hunched back on its shoulders and its large pouched bill 

 resting on its breast . It feeds by plunging head first into the water to capture fish . 



Present distribution : Breeds on the Atlantic Coast, North Carolina to Florida, Gulf Coast 

 of Florida, remanent breeding population on south coast of Texas and northern coast of 

 Mexico, Central and South America to Venezuela and Pacific Coast from Guatemala to 

 Panama, also Bahamas and Cuba. Winters more extensively on waters surrounding breeding 

 areas . 



Former distribution : Same as above, except formerly was common breeding bird on the 

 coast of Louisiana where it is now extirpated, and more common on the coast of Texas 

 and northeastern coast of Mexico . 



Status : North Gulf Coast population extirpated from Mississippi Delta to Aransas Bay . 

 Atlantic Coast population has greatly reduced reproduction resulting from thinning and 

 collapsing of eggshells . This condition is most acute at northern end of range and decreases 

 southward in eastern United States . Condition in extensive breeding range south of the 

 border largely unknown but indication of eggshell thinning in Panama. 



Estimated numbers : 8,500 breeding pairs in the United States. No estimate south of 

 border . 



Breeding rate in the wild : Usually 3 eggs, 1 to 3 young per nest. High mortality rate 

 among preflight young . 



Reasons for decline : Almost certainly caused by collapse of thin-shelled eggs or other 

 impairment of reproductive success . Thin eggshells have been shown to be associated 

 with excessive amounts of DDE in the food fishes, the contents of pelican eggs, and the 

 tissues of these birds . Dieldrin is also probably associated with lack of reproductive 

 success . 



Protective measures already taken : Protected by most States . Many colonies protected 

 by Federal and State refuges or the National Audubon Society sanctuaries. State, Federal, 

 and private cooperative research has been directed toward analysis of the thin eggshell 

 condition . 



Measures proposed : Continue present research on effects of environmental pollution and 

 of the life history and ecology of this species, but keep visits to nests to a minimum. 

 Encourage strict regulation of use of persistent chemical pesticides and the discharge 

 of wastes from plants which manufacture these products . 



Number in captivity : Several hundred. 



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