California Colonies 



Catalog Total 



5,187 bir ds 

 = colony sites 



77% 



Percent of California 

 Breeding Population. 



Breeding Chronology 



Northern California 



Clutch- 1 



Incubation Period * 42 days 



Nestling Period - 76 days 



Not Bonding 



Numbers In parentheses correspond to the 

 references from trhlch we obtained the data. 



Farallon lilandi 



playing I . 



hatching 



fledging 



adults prasent 



Channel Islands 



egg laying 



7 ;? 7 



hatching 



(28,19) 

 7 7 7 



dging 



7 7 7 



adults prasent 



Jan. | Feb. | Mar. | Apr. I May | June | July | Aug. | Sep. | Oct. | Nov. | DecT 



of non-breeding birds and some small undiscovered 

 colonies. 



Preserve. The remainder of the Channel Islands 

 have recently been designated a National Park. 



HISTORICAL STATUS AND VULNERABILITY 



Populations of Ashy Storm-Petrels along the 

 California coast have probably changed little in 

 size over the years, although little information on 

 their historical status exists. Ainley and Lewis 

 (1974) discuss the history of Ashy Storm-Petrels 

 on the Farallon Islands where observations of 

 storm-petrels were made as early as 1 862. Relevant 

 historical material for the Channel Islands is 

 summarized by Hunt et al. (1979). 



Ashy Storm-Petrel colonies can be affected 

 by disturbance by humans and terrestrial pred- 

 ators. Adults are vulnerable to surface oil slicks, 

 but fortunately they disperse widely along the 

 coast, a habit which reduces the chances that a 

 large percentage of the population will contact a 

 particular pollutant. However, during the fall 

 large numbers of Ashy Storm-Petrels are known to 

 concentrate in Monterey Bay (Ainley 1976). 



The small world population of Ashy Storm- 

 Petrels has restricted breeding and wintering 

 ranges. Each known area of concentration, both 

 during breeding and non-breeding seasons, is 

 valuable to the species. Fortunately, the most 

 important nesting sites in California are protected, 

 the Farallon Islands as a National Wildlife Refuge 

 and Santa Cruz Island as a Nature Conservancy 



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