YELLOW-HEADED BLACKBIRD (Xanthocephalus xanthocephalus) 



In springtime, marshes and ponds in Yellowstone and Grand Teton re- 

 sound with a medley of bird calls. Coots, ruddy ducks, diving ducks, 

 rails, yellowthroats, marsh wrens, and blackbirds all join in the annual 

 competition for mates and territory. One of the most striking bird inhabi- 

 tants of this marshland environment is the male yellow-headed blackbird. 

 The yellow head, neck, and chest, and the broad, white wing patch con- 

 trast sharply with the black of the bird's body and tail. The male is most 

 often seen perched in a conspicuous spot along the edge of a pond. From 

 this location he utters a variety of harsh, unmusical notes and flits com- 

 batively through the marsh defending his territory. The female is brownish 

 with a wash of yellow on the breast and with a white throat and streaked 

 lower breast. This species breeds in localized colonies throughout Yel- 

 lowstone and Grand Teton. 



Western Tanager 



Joe Van Wormer 



EVENING GROSBEAK (Hesperiphona vespertina) 



The evening grosbeak is a handsome bird with a richly colored plumage 

 and a powerful beak. The male is yellow with black wings and tail, while 

 the female is gray with black wings and tail. Both sexes have large white 

 wing patches, and the female has a yellowish cast across her back and 

 upper breast and white in her tail. During the breeding season evening 

 grosbeaks feed primarily on conifer seeds and wild berries. When the 

 breeding season has been completed evening grosbeaks congregate in 

 areas where they can feed upon the ripening chokecherries. During the 

 winter flocks of evening grosbeak descend to lower elevations to feed on 

 the seeds of seed-bearing trees such as the box elder. It is at this time that 

 the grosbeaks powerful beak comes into play. The powerful, overlapping 

 mandibles are used for shearing seeds off the trees. Evening grosbeaks 

 are fairly common permanent residents in both parks. 



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