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Baltimore Orioles
Icterus galbula
Canada |
The familiar and very vocal Baltimore Oriole Icterus galbula breeds commonly across North America eastward of the Rocky Mountains (from Alberta to Newfoundland, the Dakotas to Maine, southward to eastern Texas, Louisiana, and Georgia) and winters in Florida, the Caribbean, central Mexico and Central America to northern South America.
In the 1980s the eastern Baltimore Oriole was lumped with the western Bullock's Oriole Icterus bullockii as a single species, the Northern Oriole . Historically separated, populations of the two taxa were able to meet when trees were planted on the Great Plains allowing them to extend their ranges towards each other. Despite some differences in their appearance it was found that they interbred, and that most birds in the central plains were hybrids. Further study has shown though that in some places the birds are choosing mates assortatively (ie of their own type), and that they are not particularly closely related on a genetic level: in the mid 1990s the decision to lump the forms was reversed and they were considered as separate species again.
Male Baltimore Oriole, Point Pelee, Ontario. May 2005
Male Baltimore Orioles, Toronto, Ontario. May 2006
All photos copyright Charlie Moores
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