Fork-tailed Storm-Petrel
At a Glance
             A small, silvery seabird of cold waters off the Pacific Coast, most common off southern Alaska. Flutters low over the waves offshore, sometimes in flocks. Its center of distribution is much farther north than those of other storm-petrels in Pacific; it is able to fly well even in serious winter storms, zigzagging through wave troughs. 
          
          
             All bird guide text and rangemaps adapted from Lives of North American Birds by Kenn Kaufman© 1996, used by permission of Houghton Mifflin Harcourt Publishing Company. All rights reserved. 
          
        
        Category      
      
        Gull-like Birds, Storm-Petrels
      
    
        IUCN Status      
      
        Least Concern
      
    
        Habitat      
      
        Coasts and Shorelines, Open Ocean
      
    
        Region      
      
        Alaska and The North, California, Northwest
      
    
        Behavior      
      
        Erratic, Flap/Glide, Rapid Wingbeats, Swimming
      
    
        Population      
      
        4.000.000
      
    Range & Identification
Migration & Range Maps
     Not strongly migratory, with most remaining in far northern waters all year. In some winters, fair numbers move south to central California, rarely farther. 
  
  
Description
     8-9" (20-23 cm). Gray, with blackish on wings and around eye. Compare to Ashy Storm-Petrel (can look pale), also phalaropes. 
  
  
        Size      
      
        About the size of a Robin
      
    
        Color      
      
        Gray
      
    
        Wing Shape      
      
        Broad, Pointed, Tapered
      
    
        Tail Shape      
      
        Forked, Notched
      
    Songs and Calls
     Twittering and squeaking notes given near nest. 
  
  
        Call Pattern      
      
        Flat
      
    
        Call Type      
      
        Rattle, Raucous, Scream
      
    Habitat
     Open ocean. Favors cold waters, foraging over continental shelf and farther out to sea, sometimes fairly close to land. Extends north into Bering Sea, and may even occur around edges of floating ice. Nests on islands, mostly hilly islands with good cover of grass or shrubs. 
  
  
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    Behavior
Eggs
     One. Dull white, with fine dark dots around larger end. Incubation is by both sexes. Incubation period averages about 50 days, ranges from 37-68 days. 
  
  
Young
     Both parents feed young. At first young is fed orange oily substance regurgitated by adults, later semi-digested fish. Young fledges about 60 days after hatching, goes out to sea. 
  
  
Feeding Behavior
     Takes food from surface of water. Forages mostly by hovering and picking at surface with bill, also by dropping into water and then resuming flight, sometimes by picking at items while swimming. 
  
  
Diet
     Includes fish, crustaceans. Feeds mostly on small fish, crustaceans, and floating natural oils. Skims oily fat (from dead or wounded animals) from surface of water. Also may feed on carrion or floating refuse. 
  
  
Nesting
     Nests on islands, commonly in large colonies. Active around nesting sites only at night. Nest:  Excavates burrow in soil or uses natural rock crevices, openings in rock piles, or old burrows of other species (such as puffins). Sometimes two or more pairs have nests in side tunnels branching off from single entrance. Nest chamber usually with little or no lining added, sometimes small amount of grass. 
  
  
Conservation
Conservation Status
     Still abundant in the North Pacific, although some island colonies may have been affected by introduced rat populations.