The
island of Puerto Rico is almost rectangular in shape,
and is the smallest and the most eastern island of the Greater Antilles
.
Its coasts measures approximately 580 km, and if the adjacent islands
Vieques and Culebra are included the coast measures approximately 700
km. To the north and south seas capes measure 8.525 m for the Grave of
Puerto Rico and 5.000 m for the Grave of Tanner. In addition to the
principal island, the Commonwealth includes: Vieques, Culebra,
Culebrita, Palomino (known by some by the Spanish Virgin Islands), Mona,
Monito and various others isolated islands. Deep oceans waters fringe
Puerto Rico. The Mona Passage, which separates the island from Hispaniola
to the west, is about 75 miles (120 km) wide and more that 3,300 feet
(1,000 meters) deep. Off the northern coast is the 28,000 feet (8,500
meters) deep Puerto Rico Trench, and to the south the sea bottom descends
to the 16,400 feet (5,000 meters) deep Venezuelan Basin of the Caribbean.
Ecology
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The territory is very mountainous
(cover 60%), except in the regional coasts, but Puerto Rico offers
astonishing variety: rain forest,
deserts, beaches, caves, oceans and rivers. Puerto Rico has three main
physiographic regions: the mountainous interior, the coastal lowlands, and
the karst area.
The mountainous interior is formed by a central mountain
chain commonly known as the Cordillera Central
,
extending across the
interior of the island, from Mayagüez to Aibonito, which transects the
island from east to west. These mountain ranges are La Cordillera Central,
La Sierra de Cayey, La Sierra de Luquillo, and La Sierra
Bermeja.
The largest mountains are Cerro La Punta (1,338 m) in Jayuya; Rosas (1,267 m) found between Jayuya and Ciales, Guilarte (1,205 m) in Adjuntas, Tres Picachos (1,204 m) in Jayuya, and Maravilla (1,182m) in Ponce. Toward to the northeast is Sierra de Luquillo, whose highest peaks are: Toro Hill (1,074 m) found between Río Grande, Naguabo and Las Piedras, and El Yunque Peak (1,065 m) found in Río Grande. Another mountain chain is the Sierra de Luquillo in the northeast.
The second main physiographic feature is the coastal lowlands, which extend 13 to 19 km (8 to 12 mi) inward in the north and 3 to 13 km (2 to 8 mi) in the south. A series of smaller valleys lie perpendicular near the west and east coast. This area was originally formed by the erosion of the interior mountains.
The third important physiographic feature is the karst region in the north. This area consists of formations of rugged volcanic rock dissolved by water throughout the geological ages. This limestone region is an extremely attractive zone of extensive mogotes or haystack hills, sinkholes, caves, limestone cliffs, and other karst features. The karst belt extends from Aguadilla, in the west, to a minor haystack hills formation in Loíza, just east of San Juan.
El Yunque Peak is the
Caribbean National Forest. These 28,000 acres are
all that remain of the rain forest
that once covered much of the island (indeed, much of the entire northern
Caribbean). More than 100 billion gallons (yes, billion) of rain
fall here each year, creating a lush forest with plants of incredible
proportions and variety. A moist hike or horseback ride take you past 240
species of trees, some thousands of years old, 50 species of ferns, 20
varieties of wild orchids and riotous multitude of flowers. Living in the
forest (all over the island in fact but quite far to spot) is the tiny
coquí frog. The name is derived from his cricket like
ko-kee chirp,
this tiny creature (a quarter to one inch in size) is considered to be the
national mascot. Other forest areas are: Guajataca in the
Northwest; Río Abajo, between Arecibo and Utuado; Aguirre in the South;
Piñones, east of San Juan; Guánica, west of Ponce; Maricao, Guilarte,
Toro Negro and Carite (Guavate), all on the transinsular Panoramic Route
. The
largest number of bird species can be found at Guánica Forest, which is
home to 700 plant species of which 48 are endangered and 16 exist nowhere
else. Guánica's dry forest vegetation is unique and the Forest has been
declared an International Biosphere Reserve by UNESCO.
Puerto Rico also has some of the most important caves in the west hemisphere. The Río Camuy runs underground for part of its course, forming the third largest subterranean river in the world. There are fine examples of stalactites, stalagmites and, of course, plenty of bats. Located near to Lares, on Route 129, Km 9.8, guided tours available, open Wed to Sun, US$10 for adults, U$S7 for children. Close by you can find the Cueva del Infierno, on which 2,000 caves have been discovered; in them live 13 species of bat, the coquí, crickets, an arachnid called the "guavá", and other species. Guide tours available, for details contact (787) 898-2723.
Another unique environment can be found on Mona Island, 50 miles off the west coast of Puerto Rico. Like the Galapagos Islands, this untouched island has species which are not found elsewhere. Mona is a protected island, under the management of the United States National Park Service and the Puerto Rican Natural Resources Department. Accessible by a sometimes difficult, long boat ride, the island is available for sport diving to those who make special arrangements and are willing to rough it out.
Interesting Fact
The islands of Cayo Diablo, St. Thomas, St. John, Tortola,
Guana, Greater Camanoe, Necker Cay, and Virgin Gorda
were once known as the Puerto Rico Bank.
Terrain
Different classification schemes exist for the soils of Puerto Rico. One
physiographic approach, based on a scientific classification by the U.S. Soil
Conservation Service, can be summarized into five general soil types: humid coastal
plains, semiarid coastal plains, humid uplands, semiarid uplands, and humid upland
valleys. Another classification by soil scientists at the University of Puerto Rico
groups the island's soils into coastal lowlands, alluvium, coastal plains, alluvium
in terraces, upland dark, and upland reddish-purple. Traditionally, tropical soils
have been looked upon as infertile and unproductive and of poor agricultural
value. However, tropical countries provide such high biomass products as sugar cane,
bananas, coffee, and tobacco.
Rivers and Lakes
Puerto Rico, due to its relatively short width and its east-west
running mountain chain, does not have long rivers or large lakes.
The longest river is the Grande de Arecibo, which flows to the northern coast.
Other rivers include La Plata, Cibuco, Loíza, and, Bayamón
all draining to the north, and the Grande de Añasco, draining to the
west. There are other perennial rivers, mostly draining to the north and west.
Many of the rivers draining south run dry most of the year; nonetheless, with
heavy rainfall, they can cause flooding.
Puerto Rico does not have natural lakes, although it has 15 reservoirs, commonly called lakes, formed by damming the main rivers to produce hydroelectric power and water for irrigation. Hydroelectricity accounts for less than 1% of the electricity generated, as most electric power uses petroleum as the energy source. The island has such natural lagoons as the Condado and San Jose in San Juan, Piñones and Torrecillas in Carolina, Joyuda in Cabo Rojo, and Laguna Tortuguero in Manatí-Vega Baja.
Flora and Fauna
Several thousand varieties of tropical plants grow in Puerto Rico,
including the kapok tree ("Ceiba") with its thick trunk, the poinciana
(a prickly tropical shrub with brilliant reddish blossoms
), the breadfruit, and the coconut palm. A tropical rain
forest in the northeastern section of the island has tree ferns, orchids, and
mahogany trees; part of this tropical area is included in the Caribbean National
Forest. In the dry southwestern corner of Puerto Rico are cactus and
bunch grass. Puerto Rico has no large wild mammals. The mongoose
was brought in to control rats on sugar cane plantations. Iguanas
and many small lizards abound, and bats are present. The island has few
animals native to the island, found almost nowhere else in the world, the
coquí (mentioned above) and the Puerto Rican Parrot (Amazona vittata)
("cotorra puertorriqueña")
lives only in a few hidden areas of the
Caribbean National Forest. The Puerto Rican Parrot is bright green, about a foot
in length, with red forehead, blue primary wing feathers, and flesh-colored bill
and feet. Barracuda, kingfish, mullet, Spanish mackerel,
tuna, lobster, and oysters are among the many fish inhabiting coastal waters.
Highest Point: Cerro Punta, 1,338 m (4,389 ft)
Lowest Point: Sea level, Caribbean Sea 0 m
Natural Resources
Some stone, fish, copper and nickel, potential for on-shore and off-shore
crude oil.
- Land Use:
- arable land: 3.69%
- permanent crops: 5.59%
- other: 90.72% (2005)
Irrigated Land: 400 sq km (2003)
Natural Hazards: periodic droughts; hurricanes
- Environment Current Issues: erosion; occasional drought has caused water levels in reservoirs to drop and has prompted water rationing
Note: important location along the
Mona Passage - a key shipping lane to the Panama Canal; San Juan is one
of the biggest and best natural harbors in the Caribbean.
Hydrography
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Of the 1,200 bodies of water Puerto Rico only classifies 50 of
them rivers. Numerous rivers flow down from the mountains to distinct
coastal plains. The Central Range divides the north (Atlantic) and
south (Caribbean) watersheds. The northern rivers are long, rich and
tranquil waters in comparison to the southern rivers, and the coast
is wet and green. The major rivers are: Grande de Loíza (65
km), Bayamón (40 km), La Plata (80 km), and Grande de Arecibo (55
km). To the west and the east are the rivers basins which form the water
systems and these rivers are: Culebrinas (45 km), Grande de
Añasco (65 km), and Guanajibo (36 km). Subterranean streams are
abundant, especially toward the northwest. Between the most important
thermal fountain is "Los Baños de Coamo" found in Coamo. In the
southwest, mangroves have created a unique canal system. Puerto Rican
rivers are not navigable by large vessels, but they provide
electrical power and irrigation.
Climate
The climate is Tropical Marine with regular temperature of 80°F (26°C).
Puerto Rico enjoys warm and sunny days most of the year. Lightweight clothing
is appropriate year-round. The winds, which blow from the East, moderate
temperatures and rainfall.
In the interior, the
temperature fluctuates between 73°F
and 78°F (22°C and 25°C).
Rainfall tends to be evenly distributed throughout the year, but doubles during the months from May to October, which, unfortunately, coincides with hurricane season, as falls from November to April, with a driest period from January to April. The north coast gets twice as much rain as the south coast. Annual precipitation in the north is 1,550mm (61.02 inches); in the south is 910mm (36 inches), in coastal regions 101-381 cm (40-150 inches) and in the mountains 508 cm (200 inches).
Puerto Rico is expose to the cyclones of Caribbean, although less than Jamaica, Cuba, and the Lesser Antilles. Hurricanes frequently occur between August and October, although the U.S. National Weather Service considers the hurricane season for the North Atlantic Basin to run from June 1 to November 30. The North Atlantic Basin includes the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. Hurricane seasons during 1995-2004 have averaged 13.6 tropical storms (34-63 knots), 7.8 hurricanes (>63 knots) and 3.8 major hurricanes (>95 knots).
Dozens of hurricanes have been recorded in the island's history, but probably the most destructive was San Ciriaco, which struck on August 8, 1899.
The relative humidity is high, about 80% throughout the year.
Other Resources
- 10 Day Forecast
- 1992 Census of Agriculture

- National Weather Service Forecast Office - San Juan, PR
- Puerto Rico Perspectives (Cartographic maps)
- Current Conditions for Puerto Rico
- NOAA/AOML/Hurrican Research Division
- Puerto Rico
- Puerto Rico, Virgin Islands - Latest conditions, forecasts by USA Today
- Puerto Rico Trench
- San Juan Weather Report
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