Jehl scale analysis of today American Oystercatcher


Stan Walens
 

I received some more pictures of the bird from Aaron Gyllenhaal which show the tail and tail coverts better as well as the upperwing wing stripe.
It keys out conservatively to 34, well within the range of American Oystercatcher.

CHARACTER                             CHARACTER STATE AND SCORE

Upper tail coverts             3       white, a few black mottlings

Tail                           3       basal half of rectrices white

Edge on upper breast           3       black chest band bordered by ragged

Belly                          6       entirely white, as in palliatus

Under tail coverts             3       mainly white

Thighs                         4       entirely white, as in palliatus

Greater secondary coverts      3       6-15 mm

   (width of white edging     

   in folded wing)            

Extent of white wing stripe    2       white markings extend to outer secondaries, but not onto primaries

Underwing coverts              3       mainly white

Axillars                       4       white, as in palliatus

 


Stan Walens, San Diego
Aug. 30, 2019; 4:40 pm

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