Historic Navigation

Coral reefs today provide an economic benefit through tourism, but at one time they were considered a threat to commerce as commercial ships transporting passengers and carrying goods to U.S. and foreign ports were destroyed as they struck the shallow coral reefs. In the 19th century, the U. S. Government sought to guide mariners away from the reefs to facilitate safer maritime commerce. The stories of shipwreck and avoidance are embodied in the physical remains of these historical resources left behind.

Reefs as Shipping Hazards

Beginning in the 15th century, European exploration and colonization of the Americas brought increasing numbers of voyagers along the shores of the Florida Keys and within the reach of the treacherous coral reefs that bounded the western side of the Straits of Florida. The next several centuries saw the ruin of hundreds of vessels transiting this seaway. Even in calm weather, sailing vessels of this period were at the mercy of the Gulf Stream; the incredibly strong current pushed ships onto the reef when wind conditions were unfavorable. The Colonial Period brought more ships through this corridor as trade routes connected the New World colonies. British warships Looe (1744), Fowey (1748), and Carysfort (1771) all contributed their names to Florida Keys reefs after grounding on their sharp calcareous coral skeletons. Even highly skilled Royal Navy navigators with the best charts and navigation instruments available at that time lost their vessels to Keys coral reefs.

Improving Maritime Commerce

The U. S. Government set out to establish navigation aids as one of its first duties. The 1789 Lighthouse Act, HR-12, was the 9th Act of the first Congress. Legislators sought to install lighthouses and other aids to navigation, such as unlit beacons, at dangerous points on the American coast to guide vessel traffic safely to port and away from submerged hazards. Lacking sophisticated electronic positioning systems, like modern, satellite-based GPS, mariners relied on their experience, soundings, and nautical charts to safely reach their destination. Visible navigational aids were critical for providing information about their position.

As U.S. maritime commerce expanded, the need to accurately map the nation's coasts was also recognized. To that end President Thomas Jefferson established the United States' first scientific agency, the U. S. Coast Survey, in 1807. In addition to nautical charting, the agency performed a systematic study of the Gulf Stream, established geodetic connections between the Atlantic and Pacific coasts, and designed a tidal prediction machine.

Nonetheless, many ships were still lost to the hazardous reef surrounding the Florida Keys, so a lucrative "wrecking" industry arose to salvage goods and vessels for monetary gain. When possible, wreckers refloated grounded vessels in exchange for a salvage award. When a vessel was lost on the reef, salvaged goods were sold and the wreckers received a percentage of the recovered cargo's value. Whether a ship was refloated or lost, salvage awards were set by Key West's Admiralty Court once Key West became an official port of entry in 1822. Largely as a result of the wrecking industry's profits, Key West became the richest city in Florida. This was not surprising given that an average of one vessel per week wrecked along the Florida Keys.

Marking the Coast

Following Florida's admittance to the Union as a territory in 1821, increasing traffic between Gulf ports and the Eastern Seaboard brought mounting financial losses from shipwrecks in the Keys' waters. Merchant ship owners focused pressure on the U.S. government to take action to prevent shipping losses. In response, the U. S. Treasury Department's Lighthouse Establishment set to work marking the coast. The first attempts were lightships, anchored vessels that suspended lit lanterns from their masts. The first lightship marking the Dry Tortugas arrived in 1825 and the second took up station at Carysfort Reef in 1826. Continuing efforts to promote safe navigation led the Lighthouse Establishment to initiate permanent lighthouse structures at Cape Florida (1825), the Dry Tortugas (1826), and Sand Key (1827). However, this approach proved insufficient to warn ships away from the lengthy reef line.

Beginning in 1849, the U. S. Coast Survey spent more than 30 years in the Keys mapping and marking the reefs. Recognizing that survey signals used to triangulate the reefs were being used as navigational aids by mariners, the Coast Survey requested funding to install more permanent markers. In 1852, Lieutenant James Totten, U.S. Army Assistant in Coast Survey began erecting a series of beacons at points along the reef. The Lighthouse Establishment (which later became the Lighthouse Board) worked with the Coast Survey first on the unlit system of navigational aids and later lighthouses. This work was complemented by Professor Louis Agassiz who examined the coral reefs in 1851 under the direction of the superintendent of the U.S. Coast Survey, Alexander Dallas Bache, to find areas that had solid foundation material upon which lighthouses could be built.