Puerto Rico: Land, Climate, Plant and Animal Life
Roughly rectangular in shape, Puerto Rico extends about 111 miles (179 km) from east to west and about 39 miles (63 km) from north to south. With its principal adjacent islands of Vieques (Crab Island), Culebra, and Mona, it has a total area of 3,515 square miles (9,104 sq km). It is separated from the island of Hispaniola to the west by the Mona Passage, 75 miles (120 km) wide.
Major Physiographic Regions
Puerto Rico consists of two regions, a jumbled complex of mountains and a broken coastal plain. It is mountainous throughout three-fourths of its area. The highest peak is Cerro de Punta (4,389 feet [1,338 meters]), in the Cordillera Central, the main mountain chain of the island.
The North Coast Plain is a narrow lowland on the Atlantic coast. San Juan, the capital city, is on the plain, as are many of the island's popular beaches. San Juan Bay provides an excellent natural harbor.
Rivers, Lakes, and Coastal Waters
There are more than 1,000 small streams, in Puerto Rico, including 45 rivers that empty into the sea; all are shallow and nonnavigable. Some have carved tunnels in the mountains, creating many fascinating caves. There are no large natural lakes, although an energetic modern program of hydroelectric development has created a number of artificial lakes.
Brackish inlets and lagoons dot the 311-mile (500-km) shoreline. The principal ports for general commerce are San Juan in the north and Ponce in the south.
Temperatures and the distribution of rainfall are affected by the steady northeasterly trade winds and by the mountains over which they must climb between north and south. On the north coast, mean monthly temperatures vary between 80.5° F (27° C) in summer and 75° F (24° C) in winter; humidity is high in summer, and the relatively heavy rains, totaling about 60 inches (1,500 mm) a year, fall largely between May and December, but with no definite rainy season. Along the south coast, the temperature is slightly higher, and the rainfall in some places declines to an annual average of about 20 inches (500 mm), necessitating irrigation for agriculture. In the mountains the temperatures range from 5° to 10° F (2.8°–5.6° C) lower than on the coasts.
Plant and Animal Life
So diversified is the island geographically that its tropical vegetation includes a wide variety of species. The mangrove swamps and coconut groves of the north coast give way, farther inland and in the mountains, to mixed vegetation of the rain forest type, with orchids, tree ferns, and many kinds of trees—from the soft, light yagruma, resembling balsa, to mahogany and other tropical hardwoods. In the more arid southwest the vegetation approaches desert types, with bunchgrass and cacti.