The Gulf of Honduras, also called the Bay of Honduras, is a large inlet of the Caribbean Sea along the coasts of Mexico, Belize, Guatemala, and Honduras. From north to south it runs from Cape Catoche to Caxinas Point.
The inner Gulf of Honduras is lined by the Belize Barrier Reef which forms the southern part of the 900 km (600 mile) long Mesoamerican Barrier Reef System, the second-largest coral reef system in the world. The Belize Barrier Reef includes the Pelican Cays.
The Gulf of Honduras is marked by complex dynamics of coastal and open waters, and ocean currents, which have produced a very diverse and unique ecosystem with a wide variety of coastal marine waters, including coastline estuaries, barrier beaches, lagoons, intertidal salt marshes, mangrove forests, seagrass beds, keys and barrier reefs. The gulf receives the runoff from the watersheds of 12 rivers with an estimated discharge of 1,232,000 litres (approx. 300,000 gallons) per second.
Tourists are often taken on boat trips to the Pelican Cays, notably Caye Caulker and Ambergris Caye. In 1961 Hurricane Hattie swept across the Gulf of Honduras, destroying buildings in Belize. The infamous pirate Blackbeard spent the winter of 1717–18 harassing shipping boats sailing to and from the port of Vera Cruz, Mexico and traversing the Bay of Honduras. In April 1718, at Turneffe Atoll, Blackbeard captured the logwood cutting sloop Adventure and forced its captain, David Herriot, to join him. Blackbeard then made Israel Hands captain of the Adventure and began sailing for North Carolina.
Extent The gulf's limits have not been demarcated by the International Hydrographic Organization. Its northernmost point is variously given as Belize City, Dangriga, or Gladden Spit; its easternmost point as Punta Sal, Punta Izopo, or La Ceiba. The northern limits are in the Belize or Stann Creek districts of Belize, while the eastern ones are in the Atlántida Department of Honduras.
During the 16th through 20th centuries, the limits were thought to run from Cape Catoche to Cape Gracias a Dios.
History In 1012 December 1989, the Central American Integration System established the Commission for the Environment and Development, a body charged with coordinating environmental protection policies, projects, and programmes across the region. Upon the 12 October 1994 signing of the Alliance for the Sustainable Development of Central America, the Commission adopted its first regional environmental management plan. In 1995 and 2005, the Commission secured grant financing for its work in the gulf.
In 1996, nine NGOs in Belize, Guatemala, and Honduras established the Trinational Alliance for the Conservation of the Gulf of Honduras. The alliance seeks to harmonise members' management policies for marine and coastal protected areas in the gulf and to coordinate their management and research activities.
Geography The gulf's northern (ie Belizean) shores consist mostly of sandy beach ridges, saline tidal swamps, and shelf lagoons. It is dotted with small estuaries, mangrove forests, seagrass beds, patch and barrier reefs, and mangrove and coral cayes. The coast in the mouth of the gulf (Guatemalan coastline) consists mainly of mangrove thickets, large estuaries, seagrass beds, and beaches. The southern coast (in Honduras) is marked by long beaches, vast mangroves, and mangrove and coral cays.
The gulf's continental shelf extends some 9 to 25 miles (15–40 km) from shore. The northern shelf holds part of the Belize Barrier Reef which stretches to the Sapodilla Cayes. The shelf in the mouth of the gulf holds five parallel submarine ridges of continental origin, which jut out towards the north-northeast. It is cleaved by the Swan Island fault, which divides the North American and Caribbean tectonic plates and forms the southern boundary of the Cayman Trough.
Climate The climate is tropical or sub-tropical (ie Am and Af Köppen climate classifications). Temperature varies little throughout the year, averaging , though this is slightly moderated to by cold northerlies and trade winds blowing from North America during the winter months. Rainfall and humidity are seasonal; rainfall averages per month from June to October and per month from November to May. The wet season is brought by the annual northern migration of the Intertropical Convergence Zone. Rainfall and humidity additionally vary by location, with some 118–157 inches (3,000–4,000 mm) of annual rainfall in the coastal areas, and some in the Maya Mountains. The northeasterly trade winds are the most dominant influence on the annual wind pattern; their speeds range from to per second. Tropical storms and hurricanes are regular between August and October, with the northeastern section averaging 60 storms per century and the southwestern coast averaging 20 storms per century.
Geology The northern coast, upon the Yucatan Peninsula, reached its present location during the Late Jurassic some 150 Mya. It was joined by the Central American platform during the Eocene some 40 Mya, thereby forming a gulf or bay around its present location. The northern coast consists primarily of three geologic formations: metamorphosed sediments and granite intrusions in the Maya Mountains, and coastal alluvial sediments east, southeast, and south. The metasediments are the oldest rocks in Belize, formed during the Palaeozoic era some 300 mya. They form part of the Santa Rosa Group and are composed of fine-grained phyllite, slate, and mudstone. The alluvial sediments formed during the Tertiary period some 10 mya. Primary soil types are Ossory (from metasediments), Stopper (from granite), Melinda and Puletan (from alluvial sediment), and tintal soils (wet, swampy type soils). The Belize Barrier Reef protects the coast from open sea waves. As such, the north-south littoral drift along the coast is primarily driven by waves formed within the reef.
The Guatemalan coast at the mouth of the gulf consists primarily of alluvial material from the Quaternary era. The southern coast consists primarily of sedimentary alluvium (surficial bounders, cobbles, gravel, sand, and mud) and intrusive plutonic formations of granite, granodiorite, and diorite. These formed during the Quaternary and Cretaceous. The west-east littoral drift along the coast is driven mainly by open sea waves, which tend to approach the shoreline from east to west.
The gulf is part of the Cayman Trench, one of five deepwater basins in the Caribbean Sea. It contains the open-sea lagoon formed by the Belize Barrier Reef, Amatique Bay, the Atlantic coast of Guatemala, and the eastern part of the coast of Honduras. The western part of the gulf sits on the continental shelf, which extends offshore, and so is rather shallow, with mean depths of less than . Large freshwater discharge from the Sarstoon, Dulce, and Motagua rivers limit coral development in the mouth to a few isolated patches, as at Hunting Caye, for instance. Towards the northeast, the continental shelf drops off abruptly, from some 98 feet at the shelf break to some 6,560 feet in the Cayman Trench.
Hydrology Watersheds Eight primary and 17 subsidiary watersheds flow into the gulf. These cover some , with 2,240 sq. mi. in Belize, 7,070 sq. mi. in Guatemala, and 11,430 sq. mi. in Honduras. They contain 13 major and various minor streams with the former discharging some of freshwater per second, on average, and the latter, some 7,060 cubic feet per second, on average. Annually, the gulf receives some 17.75–18.23 cubic miles (74–76 km3) of water from its watersheds. Sedimentary discharge from Belizean rivers into the gulf was, on average, 80, 15, and 5 percent of mud, clay, and sand, respectively. Peak freshwater and sedimentary discharge occurs in the wet season, which usually exceeds dry season discharge by a factor of 59. Major watersheds Watershed Country Area Rivers Maya Mountains Belize 5,800 Sittee, Swasey, Grande, Moho Sarstoon Belize 2,218 Sarstoon Dulce–Izabal Guatemala 3,435 Dulce Motagua Guatemala 12,670 Motagua, San Francisco, Piteros, Ingleses Chamelecon Honduras 4,350 Chamelecon Cumayel Honduras 2,141 Motagua Ulua Honduras 21,230 Ulua Lean Honduras 3,045 Lean
Major rivers River Country Discharge Water Sediment Sittee Belize 32 na Stann Creek Belize 40 1.7 Swasey Belize 27 na Monkey Belize 63 2.7 Grande Belize 26 1.1 Moho Belize 37 1.6 Sarstoon Belize 160 6.9 Dulce Guatemala 300 13.0 Motagua Guatemala 530 22.9 San Francisco Guatemala na na Piteros Guatemala na na Ulua Honduras 690 29.8 Chamelecon Honduras 370 15.1
Currents The gulf's open sea experiences the Caribbean Current and a quasi-permanent cyclonic eddy generated in the southwest corner of the Cayman Trench. The latter is centred at about 19°N 86°W, generating a sea surface height anomaly of negative , with peripheral current velocities of 7.9 to 15.8 inches per second (0.2–0.4 m/s).
The Caribbean Current flows from east to west in the deep waters off the continental shelf of Honduras. Every few months it generates cyclonic, counterclockwise gyres, characterised by a central water level depression of 812 inches (2030 cm), which take 23 months to progress westwards along the Honduran coast towards the Belize Barrier Reef.
Along the northern coast, persistent northeasterly trade winds maintain a constant southerly downwelling, with speeds of 3.9 to 7.9 inches per second (0.1–0.2 m/s). This southern drift drives a counterclockwise eddy along the mouth and along the southern coast.
Tides The gulf experiences a mixed, mainly semidiurnal tide with a mean sea surface elevation range of some . The semidiurnal and diurnal constituent amplitudes range within 1.182.76 inches (0.030.07 m). The dominant semidiurnal and diurnal tidal constituents propagate westward and northward. Currents induced by the tide may be appreciable in constricted channels along the Belize Barrier Reef, reaching 15.75 inches per second (0.4 m/s). Astronomical tides are weak and at times completely dominated by meteorological tides. For instance, the storm surge associated with Hurricane Mitch raised the mean water level at Gladden Spit 9.2 feet (2.8 m) on 27 October 1998.
Waves The northeasterly and easterly trade winds give rise to both wind waves and swell, especially during December–May. These are intensified by cold northerlies and north-westerlies blowing in from North America during November–April in bursts lasting one to three days. Waves are typically 3.28–9.84 feet (1–3 m) high, with periods of 3–7 seconds, though hurricanes may increase their height to 32.81 feet (10 m) and their period to 12.7 seconds. Mean wave direction is towards 255° (ie towards the west-southwest). The wet season's thunderstorms are often accompanied by intense gusts from varying directions, followed by periods of calm.
Water