Local
- Alexandria Seaport Foundation
- Audubon Naturalist Society of the Central Atlantic States
- Audubon Society of the District of Columbia (DC Chapter of the National Audubon Society)
- Audubon Society of Northern Virginia
- Chesapeake Bay Foundation (Save the Bay)
- Entomological Society of Washington
- Four Mile Run Conservatory Foundation
- Friends of Huntley Meadows Park (Alexandria, VA)
- Friends of Little Hunting Creek
- Friends of Mason Neck State Park
- Georgetown University Laboratory of Entomology and Biodiversity (Dyke Marsh research and photos)
- Maryland Ornithological Society (Links to all Maryland Chapters)
- Mt. Vernon Sierra Club
- Northern Virginia Bird Club (Northern Virginia Chapter of the Virginia Society of Ornithology)
- Potomac Appalachian Trail Club
- Potomac Conservancy
- Potomac Riverkeeper
- Virginia Bluebird Society
- Virginia Department of Conservation and Recreation Natural Heritage Program
- Virginia Department of Game and Inland Fisheries (Web page of the Virginia Birding & Wildlife Trail)
- Virginia Institute for Marine Science
- Virginia Native Plant Society (State)
- Virginia Native Plant Society (Potowmack Chapter)
- Virginia Natural History Society
- Virginia Society of Ornithology
- Wetlands Watch
