From the time they arrive in May until they leave in early August, Bullock’s orioles (Icterus bullockii) use the hummingbird feeder outside my kitchen window with nary a hummingbird to be seen. Their bright orange and yellow plumage add color to the landscape. About the time the orioles migrate, hordes of hummingbirds, mostly rufous hummingbirds (Selasphorus rufus), appear and begin their territorial fights at the feeder.
I wondered about this phenomenon and assumed the orioles kept the hummingbirds away from the sugar water. But that might not be the reason. Instead the migration pattern of rufous hummingbirds probably explains why the hummingbirds do not appear at my hummingbird feeder until late in the summer.
Rufous hummingbirds breed further north than any other hummingbird and have one of the longest migrations of any hummingbird. These little birds breed in the Northwest from Northern California to Southern Alaska east to Idaho and Montana. They winter in Mexico, a distance of over 3,000 miles.
The migration pattern of rufous hummingbirds follows a clockwise circuit. As early as February or March they move up the coast at lower altitudes where flowers are already in bloom. Once their young are fledged, as early as late June, they fly south at higher elevations along an inland route, where alpine and other higher elevation flowers are then in full bloom. This southern migration occurs in waves with males moving out first followed by females a few weeks later. Immatures head south shortly after the females.
Rufous hummingbirds are along the coast in the spring and nest north of our area in early summer. That may explain why the orioles have no competition for the hummingbird feeders. By late summer when the hummingbirds are migrating south through Northwest California, our home, the orioles are gone. There is very little overlap between the Bullock’s orioles and rufous hummingbirds, thus no competition at the feeder.
This rufous hummingbird was photographed on a willow outside my kitchen window (near Lookout CA, Modoc County). I believe this is a male rufous hummingbird. He was in deep shadow so his throat does not show brilliant orange-red as it would in direct sunlight.