Marie Read / Eastern bluebird (Sialia sialis) male fluttering wings while perched on cherry (Prunus sp.) branch in spring, New York, USA, April.

Alan Murphy / Mountain Bluebird (Sialia currucoides) male, British Columbia, Canada

Donald M. Jones / Mountain Bluebird (Sialia currucoides) male, Montana

Donald M. Jones / Mountain Bluebird (Sialia currucoides) male in nest cavity, Troy, Montana

Oscar Dewhurst / Mountain bluebird (Sialia currucoides). Yellowstone National Park, Wyoming, USA. September.

Alan Murphy/ BIA / Mountain Bluebird (Sialia currucoides) male with insect prey, British Columbia, Canada

Alan Murphy/ BIA / Mountain Bluebird (Sialia currucoides) male with insect prey, British Columbia, Canada

Alan Murphy/ BIA / Mountain Bluebird (Sialia currucoides) male with insect prey, British Columbia, Canada

Donald M. Jones / Mountain Bluebird (Sialia currucoides) male, southwestern Montana

Donald M. Jones / Mountain Bluebird (Sialia currucoides) male, southwestern Montana

Steve Gettle / Mountain Bluebird (Sialia currucoides) male, Yellowstone National Park, Wyoming

Alan Murphy/ BIA / Mountain Bluebird (Sialia currucoides) male with insect prey, British Columbia, Canada