Cooperative Agreement (2001)
Amendment 1 adding the U.S. Forest Service
Amendment 2 adding the College of William and Mary and the National Aquarium in Baltimore
Amendment 3 adding the Natural Resources Conservation Service
Amendment 4 adding the American Bird Conservancy and James Madison University

Cooperative and Joint Venture Agreement (2006)
Amendment 1 adding Delaware State University
Amendment 2 adding U.S. Army Corps of Engineers - Civil Works, the University of Delaware, and the Academy of Natural Sciences
Amendment 3 adding National Oceanic and Atmospheric Administration and Western Pennsylvania Conservancy
Amendment 4 adding the U.S. Fish and Wildlife Service, American University, Christopher Newport University, Howard University, Indiana University of Pennsylvania, the University of Mary Washingtion, and the University of Virginia

Cooperative and Joint Venture Agreement (2011)
Amendment 1 adding George Washington University and Shippensburg University
Amendment 2 adding University of Richmond and Virginia Institute of Marine Science
Amendment 3 adding Garrett College and Virginia Commonwealth University
Amendment 4 adding Virginia Department of Conservation and Recreation’s Division of Natural Heritage

Cooperative and Joint Venture Agreement (2016)
Amendment 1 adding Shepherd University
Amendment 2 adding Virginia Tech
Amendment 3 adding Binghamton University, Bowie State University, Ecological Society of America, Longwood University, Maryland Institute College of Art, Morgan State University, Ohio University, Park Rx America, St. Mary’s College of Maryland, Stroud Water Research Center, University of Maryland Eastern Shore, and University of Pennsylvania
Amendment 4 adding Bureau of Indian Affairs and Bureau of Ocean Energy Management
Amendment 5 adding Association for the Study of African American Life and History, Bryn Mawr College, DC Department of Energy and Environment, Hood College, Lock Haven University, Mansfield University, Old Dominion University, Smithsonian Institution, Towson University, and West Virginia University
Amendment 6 adding National Aeronautics and Space Administration, American Indian Higher Education Consortium, Association of African American Museums, Gallaudet University, Indiana University, Johns Hopkins University, Live It, Learn It, Monmouth University, NatureServe, and Temple University
Amendment 7 adding Conservation Science Global, Inc.

Cooperative and Joint Venture Agreement (2021)
Amendment 1 adding Austin Peay State University, Georgetown University, Immaculata University, Marymount University, United States Naval Academy, Virginia Department of Wildlife Resources, and Chesapeake Conservancy
Amendment 2 adding Commonwealth University of Pennsylvania, replacing Lock Haven University and Mansfield University
Amendment 3 adding Monument Lab and Preservation Maryland
Amendment 4 adding Harrisburg University of Science and Technology, Biodiversity Research Institute, Chesapeake Bay Foundation, Leave No Trace, National Council on Public History, and Native Plant Trust