- Audubon Mid-Atlantic
- National Audubon
- Pennsylvania Birding Listserv
- Pennsylvania Wildlife Rehabbers
- Audubon Pennsylvania Chapters
- Audubon's Bird Guide
- Cornell Lab's Bird Guide
- Bird info from Pennsylvania Game Commission
- LycoBirds
- Bird Lore Column Articles
- Hummingbirds.net
- Audubon's Hummingbird "Get the Buzz"
- Pennsylvania Audubon At Home
- Audubon's Creating Bird-Friendly Communities
- USGS Breeding Bird Survey Analysis
- Great Backyard Bird Count
- PA Audubon's Bird-Friendly Communities
- Conserve Pa (native plants)
- Pennsylvania Native Plant Society (plant sales)
- Landscaping with Native Plants (DCNR)
- How to Attract Hummingbird (WorldBirds)