The Gulf of Mexico is among the nation's most valuable and important ecosystems. This ecosystem, consisting of offshore waters and coastal habitats of Alabama, Florida, Louisiana, Mississippi and Texas, is home to ecologically, culturally, commercially and recreationally important species of fish and wildlife. The Gulf of Mexico is an ecosystem composed of both coastal and marine environments and resources that contribute to its function, health and productivity as a single, interconnected system. The Gulf ecosystem and its natural resources are important to the U.S. economy, producing 30 percent of the nation's gross domestic product in 2009. The region provides more than 90 percent of the nation's offshore oil and natural gas production, 33 percent of the nation's seafood, 13 of the top 20 ports by tonnage in the United States in 2009, and significant recreation and tourism benefits.