Florida Keys National Marine Sanctuary was designated in 1990 and encompasses 2,900 square nautical miles surrounding the Florida Keys archipelago. The region is known world wide for its extensive offshore coral reefs; however, this subtropical region also sustains many other inter-dependent habitats including fringing mangroves, seagrass meadows, hard-bottom regions, patch reefs, and bank reefs. The Florida Keys are a partial barrier between the warm-temperate waters of the Gulf of Mexico and the tropical to subtropical waters of the Atlantic Ocean to their south. A corresponding distinction in marine flora and fauna between the two regimes is a result. This complex marine ecosystem is the foundation for the commercial fishing and tourism-based economies that are vital to south Florida.