Utah Winter Gulls

by Dennis Shirley

General Information  | Gull Identification  |  Immature Gulls  |  Key to Adult Fulls  |  Species List  |


     Gull Identification

General Considerations  

1. Immature        v

s         Adult

Mottled brown streaked    

     White Solid Colors

Dark areas in tail    

      Grays Solid Colors
        Black  Solid Colors
        White Tail

            2. Length of Immaturity  (2,3,4 year gulls)


Plumage Year

  vs  Calendar Year   Plumage Variations
Terminology      1st winter 1st year      2 year Gull = 5
  1st Summer       "      3 year gull = 7
  2nd winter 2ndyear      4 year gull = 9
  2nd Summer       "    
  3rd winter 3rd year    
  3rd Summer       "    
  4th winter 4th year    
  Adult       "    

             3. Moulting

   2 molts a year:

                 Partial in spring - head and body feathers  
  Complete in fall - all feathers (wings)  
  Primary wing feather sequence   1-10 wing feathers  

             4. Size

                 Judging can be difficult  
  Side  by side comparisons  
  Size illusions   (birds further away look bigger in a scope).

             5. Gray Tones of Adult Birds

                 Wings and Upper Parts  
  Shade of Gray  
       Sunlight and angle can affect color
       Cloudy best light  
       Side by side comparison  

             6. Sexing

                 Males larger  
  No plumage differences between sexes  
  Side by side comparison

             7. Special Features

  Ear spot  
  Pink Coloration

             8. Standing vs Flying Identification


             9. Gull Topography  (labeled photos)

  Head bill hood  
                 gonys* eye ring or crescents  
                 eye orbital ring  
                 ear spot    

  Standing     leg color, length    
                 folded wings    

  Flying upper wing    
                 under wing    
                 upper parts    
                 under parts    

* gonys or gonydeal angle = the prominent midline ridge along the lower surface of the lower mandible.



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