Ornithology Organizations and Government Agencies
American Birding Association
Central Valley Bird Club (California)
Cornell Lab of Ornithology
East Cascades Bird Alliance (Oregon)
National Audubon Society
Audubon Near You
Sacramento Audubon Society
The Audubon Dictionary For Birders
Native Bird Care & Rescue in Central Oregon (Oregon)
Sunriver Nature Center and Observatory (Oregon)
US Fish and Wildlife Service – Birding