AMERICAN PEREGRINE FALCON Falco peregrinus anatum (Bonaparte) 



Order: FALCONIFORMES Family: FALCONIDAE 



Distinguishing characteristics : Medium-sized hawk with long, pointed wings and long 

 tail. Rapid, shallow wing beats. Adult is slate gray above, wing and tail feathers and 

 flanks barred with black. Moustache marks on side face black. Throat white. Below 

 white and reddish buffy , extensively spotted and barred with black . Legs and feet 

 yellow. Immature brown above, streaked below . Larger, darker, and black markings 

 on face more extensive than Arctic peregrine (F^. £^. tundrius ); paler and more reddish, 

 less grayish below than Peale's peregrine. 



Present distribution : Breeds from non-Arctic portions of Alaska and Canada south to 

 Baja California (except coast of southern Alaska and British Columbia), central Arizona 

 and Mexico (locally); eastern limits presently follow eastern front of the Rocky Mountains 

 in the United States; distribution local in the southern boreal forests of Canada and a few 

 pairs still breed in Labrador. Winters chiefly in breeding range, but more northern 

 birds move to south. Other races occur on Pacific coast of British Columbia and southern 

 Alaska in Arctic North America and other parts of the world. 



Former distribution : Same, but breeding distribution also included Eastern United 

 States south to Georgia; also Ontario, southern Quebec and the Maritime Provinces of 

 Canada . 



Status : Extirpated as a breeding bird east of the Rocky Mountains in the United States , 

 in Ontario, southern Quebec, and the Maritimes . Local declines reported from the western 

 United States also taiga in Yukon Territory, Mackenzie District, and interior Alaska 

 (Cade and Fyfe) . Eggshell thickness reduced 15 to 20 percent since 1947 (Hickey and 

 Anderson, Cade and Fyfe, Cade et al . ) , and taiga eggs average more than 600 ppm DDE 

 (lipid basis); there is a highly significant negative correlation between shell thickness 

 and DDE concentration in eggs (Cade et al^. ) . 



Estimated numbers : Number of known aeries with adults present in 1969-70, but not all 

 producing young: British Columbia , 19 (J. Simonyi); Alberta, 3 (R . Fyfe); southern 

 Labrador, 2 (R. Fyfe); California, 2 (H. L. Leach); Oregon, 2 (D . B. Marshall); western 

 Mexico, 14 (M. Kirven); Arizona, 2 (J. Enderson); New Mexico, 2 (J. Enderson); 

 Utah, (C. M. White); Colorado, 6-8; Wyoming, 1; Montana, 1 (J. Enderson); Texas, 3-5 

 (C. M. White). Recent information lacking for Washington, Idaho, and Nevada but 

 Nelson (in Hickey, 1969) estimated only 10 to 20 percent of pairs remaining in 1965. A 

 few hundred pairs still breed in interior Alaska and taiga of Northwestern Canada princi- 

 pally along major rivers . Status in eastern Canadian boreal forest unclear but evidently 

 not numerous . 



Breeding rate in the wild : 3 or 4 eggs per set. Number of pairs laying eggs and hatching 

 success low in southern part of range (Herman et al.); reproductive rate and number of 

 breeding pairs also decreasing in taiga populations (Cade and Fyfe) . 



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