The Gulf of Mexico (Gulf) is a priceless national treasure. Its natural resources - water, fish, beaches, reefs, marshes, oil and gas - are the economic engine of the region. The Gulf is likewise vitally important to the entire nation as a bountiful source of food, energy and recreation. The Gulf Coast's unique culture and natural beauty are world-renowned. There is no place like it anywhere else on Earth. On April 20, 2010 the eyes of the world focused on an oil platform in the Gulf, approximately 50 miles off the Louisiana coast. The mobile drilling unit Deepwater Horizon, which was being used to drill an exploratory well for BP Exploration and Production, Inc. (BP), violently exploded, caught fire and eventually sank, tragically killing 11 workers. But that was only the beginning of the disaster. Oil and other substances from the well head immediately began flowing unabated approximately one mile below the surface. Initial efforts to cap the well were unsuccessful, and for 87 days oil spewed unabated into the Gulf. Oil eventually covered a vast area of thousands of square miles, and carried by the tides and currents reached the coast, polluting beaches, bays, estuaries and marshes from the Florida panhandle to west of Galveston Island, Texas. At the height of the spill, approximately 37% of the open water in the Gulf was closed to fishing. Before the well was finally capped, an estimated 5 million barrels (210 million gallons) of oil escaped from the well over a period of approximately 3 months. In addition, approximately 1.84 million gallons of dispersants were applied to the waters of the spill area, both on the surface and at the well head one mile below. Shoreline communities and other responders along the Gulf coast raced to protect coastal habitats as beaches, coastal waters, estuaries, and marshes were put at risk of oiling. Floating booms were placed across inlets, within estuaries, and along sandy beaches creating a barrier to people and to important wildlife habitats. Heavy equipment and lines of workers moved large amounts of sand to form additional berms and barriers. Some response activities to the spill negatively impacted sandy beaches and marshes as thousands of workers descended on the beaches and sensitive wetland areas preparing for the oil to come ashore, searching for oil and removing product by hand and with machines. It was an environmental disaster of unprecedented proportions. It also was a devastating blow to the resource-dependent economy of the region. While the extent of natural resources impacted by the Deepwater Horizon oil spill and response (collectively, "the Spill") is not yet fully evaluated, impacts were widespread and extensive. The full spectrum of the impacts from the Spill, given its magnitude, duration, depth and complexity, will be difficult to determine. The trustees for the Spill, however, are working to assess every aspect of the injury, both to individual resources and lost recreational use of them, as well as the cumulative impacts of the Spill. Affected natural resources include ecologically, recreationally, and commercially important species and their habitats across a wide swath of the coastal areas of Alabama, Florida, Louisiana, Mississippi, and Texas, and a huge area of open water in the Gulf. When injuries to migratory species such as birds, whales, tuna and turtles are considered, the impacts of the Spill could be felt across the United States and around the globe.