Hawk Channel is a shallow, elongated basin and navigable passage along the Atlantic coast of the Florida Keys. The channel makes up a smaller portion of the Florida Platform from Key West to the southernmost point of Key Biscayne and lies between the Keys and the Florida Reef Tract to the southeast. [1] It connects the waters of the Gulf of Mexico to the Atlantic Ocean through tidal exchanges crossing from the Florida Bay to the Straits of Florida. [2] [3] [4]
It extends roughly 230 km (120 nmi; 140 mi) from Fowey Rocks, off Key Biscayne, to Sand Key, off Key West. Its width ranges from approximately 10 km (5.4 nmi; 6.2 mi) to 0.40 km (1⁄4 mi) wide at its narrowest part. [5] [6] It varies in depth from 7 to 8 m (23 to 26 ft) off the Upper Keys along the center of the channel to 12 to 15 m (39 to 49 ft) off the Middle and Lower Keys. A course in Hawk Channel roughly 3.2 km (2 mi) offshore is partially protected by the deepwater of the Straits of Florida and allows vessels drawing roughly 2.1 to 3.0 m (7 to 10 ft) to avoid the adverse currents of the Gulf Stream while crossing through the Keys. [7] [8] [9]
Hawk Channel has an orientation parallel to the Florida Keys and serves as the continental shelf for the Florida Keys Atlantic side. It lies south or southeast between the mainland keys and an extensive reef tract 8 km (4.3 nmi; 5.0 mi) offshore. The Florida Reef Tract, a band of coral reefs along the southeast side of the Florida Keys, is located on a narrow shelf that drops off at the Florida Straits and slopes seaward at a 0.06 degree angle into Hawk Channel. A sand ridge lying between Hawk Channel known as "White Bank" is the closest of the two ridges off of the Reef Tract and is subject to open tidal exchanges with the Atlantic. The passage is considered a dividing-line between inshore non-reef and offshore reef areas. [10]
The warm, nutrient-deficient waters that circulate through this exchange are conducive to the development of patch reefs 3 to 6 m (9.8 to 19.7 ft) deep off of Hawk Channel. [11] The course along the channel is partially protected by a fringing barrier reef roughly 3 to 6 mi (4.8 to 9.7 km) offshore, limiting the effects of winds bearing northwest and sheltering the passage from the direct thrust of the Atlantic and Florida Straits. [12] The four central exchanges of South Florida coastal waters of Long Key Channel, Channel 5, Channel 2, and Moser Channel, situated perpendicular to the Keys, produce a current of up to 3 to 4 knots (5.6 to 7.4 km/h; 3.5 to 4.6 mph).
Vessels will often use beacons on the Florida Reef as guides in order to navigate through the entrance of Hawk Channel beginning 10 mi (8.7 nmi; 16 km) south of Miami's Government Cut and 3 mi (2.6 nmi; 4.8 km) south of the southern tip of Key Biscayne, with the crossover between and Biscayne Bay averaging about 4.5 ft (1.4 m) in mean low water (mlw). Most non-commercial vessels may avoid Hawk Channel due to effects of local currents and considerable commercial traffic in the Gulf Stream. Roughly 53 mi (85 km) south of Fowey Rocks, the channel cuts through John Pennekamp State Park, the adjacent federal sanctuary, and Hens and Chickens reef passed the 33 mi (53 km) length of Key Largo before continuing next 30 mi (26 nmi; 48 km) to Key West. [13] [14] Hawk Channel provides comparatively smooth waters protected from Gulf Stream powered winds except when passing through the substantial openings in the fringing reefs found 61 mi (98 km) between Alligator Reef Light and American Shoal Light. According to marine reports, the local current predominately sets fair with the channel except alongside the opening between Hawk Channel and Biscayne Bay where fairly strong crosscurrents exist most notably during an ebb tide. [15]
The channel runs systemically with the Florida Current pushing water northward from the Atlantic with a velocity of 1.8 m/s (3.5 kn) and a mean transport of 30 Sv. Hawk Channel's ocean floor also makes up the eastern escarpment of the Florida Platform where the Florida Peninsula lies 3 to 4 mi (4.8 to 6.4 km) from the platform's edge. Sand Key Light, the marker indicating the southernmost portion of the channel, is located 6 nmi (11 km; 6.9 mi) southwest of Key West, between Sand Key Channel and Rock Key Channel, two of the channels into Key West, on a small sand covered reef. [16] [17] Hawk Channel contains an estimated 1,000 or more shipwrecks in its waters. A popular diving trail consisting of nine notable wrecks along the channel are designated as "Shipwreck Trail" under the Florida Keys National Marine Sanctuary. [18] [19]
Although the exact origins of the name remain largely uncertain, Hawk Channel has been a prominent site for birdwatching; the prolonged bird migration in the fall season goes on from early July until late November where large flights of broad-winged hawks, as well as merlins, and peregrine falcons, are predominant during the September–October migration. [20]
Prior to the Spanish occupation of Florida, the Florida Keys and its surrounding waters, including Hawk Channel, were inhabited by the Calusa and Tequesta tribes. On 15 May 1513, the Spanish explorer, Juan Ponce de León, and his fleet sailed south from Biscayne Bay along Hawk Channel through the Florida Keys. While charting the surrounding waters, he named the islands Los Martires ("The Martyrs"), as they reminded him of suffering men from a distance. [21]
Beginning as early as the 16th century, numerous merchant ships wrecked off of the shallow reefs of Hawk Channel while sailing along notable shipping lanes within the Gulf Stream, expanding the prosperous wrecking industry off of the Southern coast of the Keys. Increasing revenues brought the islands' first settlements in 1822, bringing the fishing industry's use of the passage with it. In 1733, a hurricane wrecked 19 ships of the Spanish treasure fleet on Florida Reef along Hawk Channel. The remaining survivors camped on the nearby Indian Key until they were rescued.
With the construction of Henry Flagler's Overseas Railroad in 1905, four predominant channel passages were dredged perpendicular to the Keys and the railroad's various bridge extensions, including Moser Channel through the Seven Mile Bridge. These channels allowed the passage of boats and tidal exchanges from the Florida Bay and the Intercostal Waterway into Hawk Channel. Additional channels include Long Key Channel, Channel 5, and Channel 2. [22]
In November 1822, the USS Alligator ran aground on a shallow reef off of Hawk Channel while escorting a convoy of merchant vessels. The United States later sank her in order to prevent its remains from being salvaged by pirates. The wreck lies 4 nautical miles (7.4 km; 4.6 mi) east of Indian Key, near the Matecumbe Keys, north of Alligator Reef itself, and is marked by the Alligator Reef Lighthouse. [23]
In June 1748, the Royal Navy frigate HMS Fowey struck a reef off of Hawk Channel. She sank on 26 June. A few miles south of Cape Florida, the Fowey Rocks Lighthouse, named after the frigate, was constructed in 1878. While construction was still underway, the SS Arratoon Apcar ran aground on the reef.
In 1858, the Sombrero Key Light, the tallest lighthouse in the Florida Keys, was put in service located on a mostly submerged reef that had been referenced in old Spanish charts but had eroded away during the 19th century. The lighthouse now lies near the Sombrero Key Reef.
Between 1921 and 1935, the unmanned reef lights of Molasses Reef Light, Pacific Reef Light, Hen and Chickens Shoal Light, Smith Shoal Light, and Tennessee Reef Light were erected as navigational aids and Daymarks along Hawk Channel to mark shallow hazards. [24]
On 4 August 1984, the motor vessel Wellwood ran aground on the upper fore-reef on Molasses Reef southeast off of Key Largo in 6 metres of water, resulting in the destruction of 5,805 square meters of living corals. The wreck remained grounded for 12 days before it was removed by the U.S. Coast Guard. [25]
A screw-pile lighthouse is a lighthouse which stands on piles that are screwed into sandy or muddy sea or river bottoms. The first screw-pile lighthouse to begin construction was built by the blind Irish engineer Alexander Mitchell. Construction began in 1838 at the mouth of the Thames and was known as the Maplin Sands lighthouse, and first lit in 1841. However, though its construction began later, the Wyre Light in Fleetwood, Lancashire, was the first to be lit.
Biscayne National Park is a national park of the United States located south of Miami, Florida, in Miami-Dade County. The park preserves Biscayne Bay and its offshore barrier reefs. Ninety-five percent of the park is water, and the shore of the bay is the location of an extensive mangrove forest. The park covers 172,971 acres and includes Elliott Key, the park's largest island and northernmost of the true Florida Keys, formed from fossilized coral reef. The islands farther north in the park are transitional islands of coral and sand. The offshore portion of the park includes the northernmost region of the Florida Reef, one of the largest coral reefs in the world.
The Florida Keys are a coral cay archipelago off the southern coast of Florida, forming the southernmost part of the continental United States. They begin at the southeastern coast of the Florida peninsula, about 15 miles (24 km) south of Miami and extend in an arc south-southwest and then westward to Key West, the westernmost of the inhabited islands, and on to the uninhabited Dry Tortugas. The islands lie along the Florida Straits, dividing the Atlantic Ocean to the east from the Gulf of Mexico to the northwest, and defining one edge of Florida Bay. The southern part of Key West is 93 miles (150 km) from Cuba. The Keys are located between about 24.3 and 25.5 degrees North latitude.
Key Biscayne is an island located in Miami-Dade County, Florida, located between the Atlantic Ocean and Biscayne Bay. It is the southernmost of the barrier islands along the Atlantic coast of Florida, and lies south of Miami Beach and southeast of Miami. The key is connected to Miami via the Rickenbacker Causeway, originally built in 1947.
The Florida Keys National Marine Sanctuary is a U.S. National Marine Sanctuary in the Florida Keys. It includes the Florida Reef, the only barrier coral reef in North America and the third-largest coral barrier reef in the world. It also has extensive mangrove forest and seagrass fields. The Florida Keys National Marine Sanctuary, designated on December 28, 1990, was the ninth national marine sanctuary to be established. The Florida Keys National Marine Sanctuary protects approximately 2,900 square nautical miles of coastal and ocean waters from the estuarine waters of South Florida along the Florida Keys archipelago and the Hawk Channel passage, encompassing more than 1,700 islands, out to the Dry Tortugas National Park, reaching into the Atlantic Ocean, Florida Bay, and the Gulf of Mexico.
The Cape Florida Light is a lighthouse on Cape Florida at the south end of Key Biscayne in Miami-Dade County, Florida. Constructed in 1825, it guided mariners off the Florida Reef, which starts near Key Biscayne and extends southward a few miles offshore of the Florida Keys. It was operated by staff, with interruptions, until 1878, when it was replaced by the Fowey Rocks lighthouse. The lighthouse was put back into use in 1978 by the U.S. Coast Guard to mark the Florida Channel, the deepest natural channel into Biscayne Bay. They decommissioned it in 1990.
Alligator Reef Light is located 4 nautical miles east of Indian Key, near the Matecumbe Keys of Florida in the United States, north of Alligator Reef itself. The station was established in 1873. It was automated in 1963 and was last operational in July, 2014, and is being replaced by a 16' steel structure with a less powerful light located adjacent to it. The structure is an iron pile skeleton with a platform. The light is 136 feet (41 m) above the water. It is a white octagonal pyramid skeleton framework on black pile foundation, enclosing a square dwelling and a stair-cylinder. The lantern is black. The original lens was a first order bivalve Fresnel lens. The light characteristic of the original light was: flashing white and red, every third flash red, from SW by W 1/2 W through southward to NE 1/8 E, and from NE by E 3/4 E through northward to SW 3/8 S; flashing red throughout the intervening sectors; interval between flashes 5 seconds. It had a nominal range of 14 nautical miles in the white sectors and 11 nautical miles in the red sectors. The new light has a range of approximately 7 nautical miles.
Fowey Rocks Light is located seven miles southeast of Cape Florida on Key Biscayne. The lighthouse was completed in 1878, replacing the Cape Florida Light. It was automated on May 7, 1975, and as of 2021 is still in operation. The structure is cast iron, with a screw-pile foundation, a platform and a skeletal tower. The light is 110 feet above the water. The tower framework is painted brown, while the dwelling and enclosed circular stair to the lantern is painted white. The original lens was a first-order drum Fresnel lens which stood about 12 feet (4 m) high and weighed about a ton (tonne). The light has a nominal range of 15 miles in the white sectors, and 10 miles in the red sectors. It serves as a maker for the entrance to the Hawk Channel passage through the Florida Keys.
The maritime history of Florida describes significant past events relating to the U.S. state of Florida in areas concerning shipping, shipwrecks, and military installations and lighthouses constructed to protect or aid navigation and development of the Florida peninsula.
A pile lighthouse is a type of lighthouse found in Australia, the United Kingdom and United States. In the United States they are found primarily in Florida, including on open reefs adjacent to the Florida Keys.
HMS Fowey was a fifth-rate warship of the Royal Navy, launched on 14 August 1744 in Hull, England. She spent only four years in commission before she struck a reef and sank in what is known today as Legare Anchorage in Biscayne National Park, off the coast of Florida. She was armed with six, nine, and eighteen pounder guns and crewed by more than 200 men.
The Florida Reef is the only living coral barrier reef in the continental United States. It lies a few miles seaward of the Florida Keys, is about 4 miles wide and extends along the 20-metre (66 ft) depth contour 270 km from Fowey Rocks just east of Soldier Key to just south of the Marquesas Keys. The system encompasses more than 6,000 individual reefs. Florida waters are home to over 500 marine fish and mammal species along with more than 45 species of stony corals and 35 species of octocorals.
Carysfort is a coral reef located within the Florida Keys National Marine Sanctuary. It lies to the east of Key Largo, within the Key Largo Existing Management Area, which is immediately to the east of John Pennekamp Coral Reef State Park. This reef is within a Sanctuary Preservation Area (SPA). The reef is northeast of The Elbow. The Carysfort Reef Light is near the center of the SPA.
Alligator Reef is a coral reef located within the Florida Keys National Marine Sanctuary. It lies to the southeast of Upper Matecumbe Key. This reef lies within a Sanctuary Preservation Area (SPA).
SS Arratoon Apcar was an iron-hulled sail and steam merchant ship that was built in Scotland in 1861 and wrecked off the coast of Florida in 1878. Her wreck in shallow water on Fowey Rocks is now a scuba diving site.
The following index is provided as an overview of and topical guide to Wikipedia's articles on recreational dive sites. The level of coverage may vary:
Recreational dive sites are specific places that recreational scuba divers go to enjoy the underwater environment or for training purposes. They include technical diving sites beyond the range generally accepted for recreational diving. In this context all diving done for recreational purposes is included. Professional diving tends to be done where the job is, and with the exception of diver training and leading groups of recreational divers, does not generally occur at specific sites chosen for their easy access, pleasant conditions or interesting features.
Margaret Brock Reef is a reef in the Australian state of South Australia located in the state's coastal waters on its south-east coast about 7 kilometres (4.3 mi) west of the headland of Cape Jaffa and about 27.2 kilometres (16.9 mi) south-west of the town of Kingston SE. It is the site of both a navigation aid which operated as a staffed lighthouse from 1872 to 1973 and as an automatic beacon onward to the present day, and a rock lobster sanctuary declared under state law in 1973. It is named after the barque Margaret Brock which was wrecked there in 1852.
The Looe Key National Marine Sanctuary was a National Marine Sanctuary in the waters in the Florida Keys in Florida in the United States that existed from 1981 to 1990. It protected Looe Key, a coral reef south of Big Pine Key. In 1990, it was subsumed by the new Florida Keys National Marine Sanctuary, which included its waters. However, it continued to operate until 1997, when it was fully integrated into the Florida Keys sanctuary.
The Key Largo National Marine Sanctuary was a National Marine Sanctuary in the waters in the Florida Keys in Florida in the United States that existed from 1975 to 1990. It was the second national marine sanctuary, and it protected the portion of a barrier reef beyond Florida state waters in John Pennekamp Coral Reef State Park. In 1990, it was subsumed by the new Florida Keys National Marine Sanctuary, which included its waters. However, it continued to operate until 1997, when it was fully integrated into the Florida Keys sanctuary.