• National Park Service
• US Forest Service
  • Pacific Southwest Research Station - Redwood Science Laboratory
• Bureau of Land Management
• US Fish and Wildlife Service

• CA Department of Fish and Game (DFG)
• DFG - Habitat Conservation Planning

• California Bat Conservation Fund
• Bat Conservation International
• Key to Bats of Central California

• Redwood Region Audubon Society
  Local chapter offers field trips, program meetings, and more.

Local Birding Workshops and Classes

• LBJ Enterprises
  Biological consulting, birdwatching tours, birdwatching classes, bird books and birding resources for Northern California and beyond.
  
• Mad River Biologists
  Offers several training courses which provide participants with specialized bird observer, identification, and surveying skills.
  

Birding Festivals

• Godwit Days
  Birding festival held at the peak of spring migration, shorebirds abound and special opportunities are planned to see many other species including Marbled Murrelet, Spotted Owl and Snowy Plover.
• Annual Aleutian Goose Festival

Wolves

• International Wolf Center

Mountain Lions

• Mountain Lion Foundation

Bears

• The International Association for Bear Research and Management

Other Organizations

• National Wildlife Federation
• American Society of Mammologists
• The Society for Northwestern Vertebrate Biology

Wildlife Tracks

• Mammal Tracks