Yellow Grosbeak x Black-headed Grosbeak

Yellow Grosbeak x Black-headed Grosbeak hybrid, Tucson Sonoran Desert Museum (Arizona, USA), December 2010 - copyright Steve Mlodinow

(photo ID: 1485)

This is a captive bird in a museum that specialises in species that are native to the Sonoran Desert.  I gather it mainly stocks Black-headed Grosbeaks but must have had at least one Yellow Grosbeak (a rare vagrant in Arizona) at one point.
 

Yellow Grosbeak x Black-headed Grosbeak hybrid, Tucson Sonoran Desert Museum (Arizona, USA), December 2010 - copyright Steve Mlodinow

(photo ID: 1485)

Yellow Grosbeak Pheucticus chrysopeplus
Black-headed Grosbeak Pheucticus melanocephalus