Hybrid Bullock's X Baltimore Oriole (Icterus bullockii X I. gabula), Paradise, Cochise County

This hybrid Bullock's X Baltimore Oriole was identified by Judy Engelmann and photographed by Jackie Lewis on 09 May 2010 at a part-time home behind the George Walker House in Paradise.

Populations of Bullock's and Baltimore Orioles first came into contact following the conversion of the Great Plains to agriculture and the consequent planting of trees which allowed Baltimore's to spread west and Bullock's to spread east.  As often happens when closely related species first come in to contact, hybrids were initially very common.  The caused the two species to be lumped for a while as "Northern Oriole."  However, these hybrids were less fit and birds that tended to hybridize had lower reproductive success and were soon eliminated from the population by natural selection.  Hybrids like these are now much rarer and Bullock's and Baltimore Orioles frequently breed side by side in their zone of overlap without hybridization.  As a result, they were restored to full species status in 1995. 

Note the intermediate pattern of the head and wings.

09 May 2010, photo by Jackie Lewis

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