U.S. NIS Sites:

• The Sea Grant Nonindigenous Species Site 
• Aquatic Bioinvasions Research and Policy Institute
• Maryland Sea Grant Invasive Species
• InvasiveSpecies.Gov
• MIT Sea Grant College Program: Exotic Species Web Pages
• Non-Native Aquatic Species in the Gulf of Mexico and South Atlantic Regions
• Sea Grant Minnesota: Exotic Species
• Nonindigenous Aquatic and Selected Terrestrial Species of Florida
• Pearl Harbor Legacy Project at the Bishop Museum, Hawaii
• Nonindigenous Aquatic Species in Washington State and Adjacent Waters
• ANS Task Force
• Exotic Species in the Great Lakes Region (on the Great Lakes Information Network)
• Great Lakes Panel on Aquatic Nuisance Species
• Virginia Institute of Marine Science Rapa Whelk Research in the Chesapeake Bay
• Sea Grant's National Aquatic Nuisance Species Clearinghouse
• US Geological Survey Nonindigenous Aquatic Species Program
• Invasive Species in the News
• Prince William Sound Regional Citizens' Advisory Council

Foreign NIS Sites:

• Canadian Aquatic Invasive Species Network
• Centre for Research on Introduced Marine Pests (Australia)
• The Cawthron Institute Biosecurity Programmes (New Zealand)
• CIESM Atlas of Exotic Species in the Mediterranean Sea
• Baltic Sea Alien Species Database
• Regional Biological Invasions Centre

Legislation Regarding Aquatic Nuisance Prevention:

• National Invasive Species Act of 1996
• Federal Resource Laws of the U.S. Fish and Wildlife Service

Ballast Water Sites

• International Maritime Organization (IMO) Ballast Water Exchange Guidance
• EPA: Oceans, Coasts, and Estuaries
• Stemming the Tide: Controlling Introductions of NIS by Ships' Ballast Water
• Gulf of Maine Times news article "Ballast water a vehicle for exotic marine species invasions"
• Coast Guard Ballast Water Management