Dry Tortugas

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The Dry Tortugas are a small group of islands, located at the end of the Florida Keys, USA, about 113 km west of Key West, and 60 km west of the Marquesas Keys, at 24°38′00″N, 82°55′12″W, the closest islands. Still further west is the Tortugas Bank, which is completely submerged. The islands were discovered in 1513 by Spanish explorer Juan Ponce de León. They are an unincorporated area of Monroe County, Florida and belong to the Lower Keys Census County Division.

Contents 1 Geography 1.1 Islands (keys) 1.2 Former Islands 1.3 Shoals with lights 2 Environment 3 History 4 External links

[edit] Geography

The keys are low and irregular, and have a thin growth of mangrove. In general, they rise abruptly from deep water. They are continually changing in size and shape. The Tortugas Atoll has had up to 11 islets during the past two centuries. Some of the smaller islands have disappeared and reappeared multiple times as a result of hurricane impact.

[edit] Islands (keys)

The total area of the islets, some of which are little more than sand bars just above the water mark, is about 580,000 m². Especially the area figures of the smaller keys are subject to change over time. There are seven islets, which are from West to East:

• Loggerhead Key, with Dry Tortugas lighthouse' (46 meters high), 250 by 1200 meters in size, with an area of 260,000 m² the largest, 1 meter high,
• Garden Key, with Fort Jefferson, and inactive Garden Key lighthouse over 20 meters high in the southeast, 4 km east of Loggerhead Key, 400 by 500 meters in size, with an area of 170,000 m² the second largest. The original size, before construction of Fort Jefferson, has been estimated at 30,350 to 35,610 m².

• Bush Key (formerly Hog Island, because of the hogs that were raised there to provide fresh meat for the prisoners at Fort Jefferson), just a few meters east of Garden Key (actually connected by a sand bar since 1998), 150 by 900 meters in size, area 120,000 m² (making it the third largest), less than 1 meter high. Bush Key is the site of a large tern rookery. It is closed to visitors from April to September to protect nesting Sooty Terns and Noddy Terns.

• Long Key, 50 meters south of the eastern end of Bush key, 50 by 200 meters in size, area 8,000 m²
• Hospital Key, so called because a hospital for the inmates of Fort Jefferson had been built there in the 1870s (formerly called Middle Key or Sand Key), 2.5 km northeast of Garden Key and Bush Key, 70 meters in diameter, area 4,000 m², 1 meter high
• Middle Key, 2.5 km east of Hospital key, 90 meters in diameter, area 6,000 m²
• East Key, 2 km east of Middle Key, 100 by 200 meters in size, area 16,000 m², over 2 meters high

The three westernmost keys, which are also the three largest keys (Loggerhead Key, Garden Key, and Bush Key), make up about 93 percent of the total land area of the group.

[edit] Former Islands

Formerly existing keys were, from West to East:

• Southwest Key, disappeared by 1875, today a shoal South off Loggerhead Reef
• Bird Key (formerly Booby Key), was about 1.5 km southwest of Garden Key, disappeared in 1935, current names in the area are Bird Key Bank and Bird Key Harbor
• North Key, probably identical with former Booby Island, current name in the area is North Key Harbor, an anchorage WSW of Pulaski Shoal, disappeared by 1875
• Northeast Key (earlier called Sand Key), was between East Key and North Key, slightly to the North, disappeared by 1875

[edit] Shoals with lights

• Pulaski Shoal (Pulaski Reef), marking the northeast edge of the group at 24°41′36″N, 82°46′24″W, is not an island, but the former location of the Pulaski Shoal Light.
• Iowa Rock, halfway between Garden Key and Hospital Key, is another site of a navigational light (and weather station) built in shallow water. It was destroyed by Hurricane Hugo, with three bare stumps left.

[edit] Environment

The islands get their name from their distinctive characteristics: Dry because none of the islands have fresh water and Tortugas because seafarers stopped at the islands to take sea turtles, which they kept on their backs in the holds of sailing ships and butchered when they wanted fresh meat. They are not related to the Caribbean island of Tortuga, near Hispaniola.

The islands are home to Dry Tortugas National Park, and are only accessible by boat or seaplane, making them a popular birding destination. The large seabird colony, includes Sooty Terns, Brown Noddy, Masked Booby and Magnificent Frigatebird, and the regular occurrence of Caribbean vagrant birds.

[edit] History

The islands were discovered in 1513 by the Spanish Explorer Ponce De Leon. They were then given the name Las Tortugas (The Turtles) due to the abundance of sea turtles found on the islands and surrounding shoals. Soon there after, the word 'Dry' was added to the name to indicate to mariners of the islands lack of fresh water.

In 1861, the United States government completed Fort Jefferson on Garden Key, and this bastion remained in Union hands throughout the Civil War. It later was used as a prison until abandoned in 1874. During the 1880s, the Navy established a base at Tortuga; and it subsequently set up a coaling (refueling) and a wireless (radio) station there as well. During World War I, a seaplane base was established on the islet; but it was abandoned soon thereafter.

An account of a visit to the fort at the Dry Tortugas by President Franklin D. Roosevelt and Justice-to-be Robert H. Jackson can be found in the book, That Man: An Insider's Portrait of Franklin D. Roosevelt, by Robert H. Jackson, edited and introduced by John Q. Barrett (Oxford University Press, New York, 2003).

In August 2004, the Dry Tortugas were directly struck by Hurricane Charley. The following day, a Cessna airplane crashed into the water near the islands, killing cinematographer Neal Fredericks while he was filming scenery for the feature film Cross Bones.

[edit] External links

• Topographic and Floristic Change of the Dry Tortugas Keys (PDF)
• Dry Tortugas National Park Official National Park Service Site
• Dry Tortugas National Park by Park Vision A Photographic Guide to the Park.
• Dry Tortugas Satellite View Google Maps
• History and Ecology of Mangroves in the Dry Tortugas

Edit	Florida Keys
Biscayne National Park	Soldier Key, Ragged Keys, Boca Chita Key, Sands Key, Elliott Key, Adams Key, Old Rhodes Key, City of Islandia
Upper keys	Key Largo (island), North Key Largo (CDP), Key Largo (CDP), Tavernier (CDP), Plantation Key (island), Plantation Key (former CDP), Windley Key, Upper Matecumbe Key, Indian Key, Lignumvitae Key, Lower Matecumbe Key, Village of Islamorada
Middle keys	Craig Key, Fiesta Key, Long Key, City of Layton, Conch Key, Duck Key (CDP), Grassy Key, Crawl Key, Long Point Key, Fat Deer Key, Key Vaca, City of Marathon, City of Key Colony Beach, Boot Key, Knight's Key, Pigeon Key
Lower keys	Little Duck Key, Missouri Key, Ohio Key, Sunshine Key, Bahia Honda Key, Spanish Harbor Keys, West Summerland Key, No Name Key, Big Pine Key (CDP), Little Torch Key, Middle Torch Key, Big Torch Key, Ramrod Key, Summerland Key, Knockemdown Key, Cudjoe Key (CDP), Sugarloaf Key, Park Key, Lower Sugarloaf Key, Saddlebunch Keys, Shark Key, Geiger Key, Big Coppitt Key (CDP), East Rockland Key, Rockland Key, Boca Chica Key, Key Haven, Stock Island (CDP), Key West, Sunset Key, Wisteria Island
Outlying islands	Mule Keys, Marquesas Keys, Dry Tortugas, Tortugas Bank
Areas	Florida Bay, Dry Tortugas National Park, Florida Keys National Marine Sanctuary, National Key Deer Sanctuary, John Pennekamp Coral Reef State Park, Biscayne Bay, Biscayne National Park, Key West National Wildlife Refuge, Great White Heron National Wildlife Refuge, Crocodile Lake National Wildlife Refuge
Other topics	Monroe County, Conch Republic, Overseas Highway, Overseas Railroad, Card Sound Bridge, Seven Mile Bridge, Bahia Honda Bridge, Theater of the Sea, Hurricane Georges, Labor Day Hurricane of 1935, Key Deer, Ocean Reef Club, Key lime pie