CALIFORNIA BROWN PELICAN Pelecanus occidentalis californicus (Ridgway) 



Order: PELECANIFORMES Family: PELECANIDAE 



Distinguishing characteristics : A large, dark gray-brown water bird with bare skin pouch 

 on underside of long bill. Much white on head and neck of adults. Immatures have dark 

 heads. Soaring flight with head folded back, bill resting on chest. Differs from eastern 

 brown pelican in larger size and in having brown color of back of neck darker, almost 

 black, and skin sac under bill reddish instead of greenish during the breeding season. 



Present distribution : Breeds locally on islands along the Pacific Coast from Anacapa 

 Island, Ventura County, California; Los Coronados, San Martin, and San Benito Islands 

 off the coast of Baja California; islands in the Gulf of California; and south to Tres Marias 

 Islands off Nayarit. Postbreeding movement of birds northward along the Pacific Coast 

 in late summer and fall . 



Former distribution : Same. Historically nested on Santa Cruz, San Miguel Islands, 

 Santa Barbara County and Monterey County, California. 



Status : Much reduced from former numbers in breeding colonies and as non-breeding birds 

 off the coasts of California and Baja California. Reproduction on Anacapa Island, California, 

 and Los Coronados and San Martin Islands, Baja California, was almost entirely unsuccessful 

 from 1969 to 1972. Reproduction on San Benito Island, Baja California, 400 miles south of 

 United States border, and remote islands in the Gulf of California varies. Success on 

 islands farther south is more satisfactory . 



Estimated numbers : Declining about 1,000 to 1,500 adults local to California in 1972. 

 Declining 14 to 18 percent per year in California. Minimum population for Mexico and 

 California over 100,000. 



Breeding rate in the wild : Two or three eggs per set. 



Reasons for decline : Poor reproductive success due to collapsed eggs because of thin 

 shells, suspected to result from food contamination with DDE and/or other pollutants. 

 Tourist disturbance to some Mexican colonies . 



Protective measures already taken : State, Federal, and private cooperative research has 

 been directed toward analysis of the thin eggshell condition and resulting reproductive 

 success. Waste discharges from plants being corrected. Population surveys being made 

 by Bureau of Sport Fisheries and Wildlife. 



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

 life history and reproductive biology, 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 . Encourage sanctuary status for nesting colonies . 



Number in captivity : Unknown , 



Breeding potential in captivity : Probably slight . 



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