$Unique_ID{COW00893} $Pretitle{226} $Title{Colombia Chapter 2A. Geography and Population} $Subtitle{} $Author{Howard I. Blutstein} $Affiliation{HQ, Department of the Army} $Subject{colombia cordillera lowlands near population zone country department pacific river} $Date{1977} $Log{} Country: Colombia Book: Colombia, A Country Study Author: Howard I. Blutstein Affiliation: HQ, Department of the Army Date: 1977 Chapter 2A. Geography and Population Located in the northwest corner of the South American continent, Colombia is the only country of South America with both Atlantic and Pacific coastlines. It has maximum dimensions of 1,200 miles north to south and 800 miles east to west, and its approximately 440,000 square miles of territory make it fifth largest in size of the Latin American countries. Colombia had a 1976 population of about 25 million people and had probably at some point in the early 1970s replaced Argentina as the third largest country of the region and the fourth largest of the Western Hemisphere in population. The country is dominated by three ranges of the Andes Mountains that cross the country on a northwesterly axis in the form of a trident. The greatest concentration of population is in plateaus and basins scattered among these ranges and in the valleys of the two great rivers that separate them. West of the Andes are two coastal lowlands. The Atlantic Lowlands consist largely of open land, much of it swampy; there is extensive cattle raising and plantation agriculture there, as well as heavy concentrations of population around the several port cities. The narrower Pacific Lowlands are swampy, heavily forested, and sparsely populated. East of the Andes lies a great interior plain crossed from east to west by many large rivers. Consisting principally of open land in the north and tropical jungle in the south, it has few settlements and remains largely undeveloped. Although Colombia is located within a few degrees of the equator, the varied elevations of its extensive highlands give it an assortment of climates. Most of the population resides in the highlands, but the diversity of climates and the varied soils allow for a rich variety of tropical and temperate vegetation and wildlife. There are numerous mineral resources, and the country's coal reserves are the most extensive in South America. The preliminary summary data from the 1973 population census did not appear until 1975, and in early 1976 it was still necessary to rely extensively on the 1964 census and on surveys for demographic information. It appeared, however, that the very high rate of population growth had slackened progressively during the late 1960s and early 1970s, in part as the consequence of an energetic family planning program. Since World War II population growth had been fastest in the cities, where migrants from the countryside had been arriving in increasing numbers in search of better employment opportunities. The greatest number came to Bogota, but in the mid-1970s ten cities had attained populations of 200,000 or more. This dispersed pattern of urban settlement was unusual in Latin America, where in most countries a single city predominated. In Colombia, however, the broken terrain of the highlands had made communication difficult, and the urban centers and their agricultural hinterlands had grown in virtual isolation; no dominant center had gained population at the expense of the others. With the progressive migration from country to town, agricultural employment has experienced a relative decline, and employment in the urban industrial and services sectors has risen. In the early 1970s agricultural employment was only slightly greater than that in the service occupations, which were the fastest growing. Unemployment has increased with the corresponding growth of the labor force's urban sector, particularly in the large cities, where in the mid-1970s it had become a serious social and economic problem. Boundaries and Political Subdivisions There are no outstanding international boundary problems. Frontiers with Panama, Brazil, Peru, and Ecuador have been demarcated by completed surveys and placement of markers. The boundary with Venezuela has been entirely delineated by international agreement but has not been fully demarcated. The Venezuela frontier, after repeated delays, was first delineated in 1883, and a definitive treaty settling a few remaining issues was signed in 1941. Most of the 1,379-mile border runs through tropical wilderness where, in some localities, hostile Indians have discouraged survey operations. In general the northern third of the boundary follows mountain features from the Gulf of Venezuela to the Arauca River on the rim of the Eastern Plains (Llanos Orientales). Thereafter the border is mainly riverine with straight lines connecting the rivers. The 1,022-mile boundary with Brazil, located in remote tropical jungle, consists of arbitrary straight lines broken occasionally by rivers. The 1,010-mile boundary with Peru follows a short stretch connecting the Amazon on the eastern flanks and a straight line northward to the Putumayo River, which the border then follows to the Ecuador frontier. The border with Ecuador is 364 miles in length. It follows the Putumayo and San Miguel rivers westward to the eastern slopes of the Andes, where it turns northward along a complex line of watersheds, streams, and straight lines to the Pacific coast. In the scantily populated jungles of eastern Colombia, most of the towns are river ports located on or close to the frontiers. The 166-mile border with Panama passes through tropical rain forest where the topography consists of narrow coastal plains, rugged mountains, and a central lowland. This border is demarcated by water divides and by fourteen boundary pillars placed on prominent elevations. In the mid-1970s there were no outstanding claims to territories in adjoining states. The Association of Retired Military Officers, however, complained in 1974 that since the beginning of the century some 280,000 square kilometers (108,000 square miles) of claimed territory had been lost, beginning with the secession of Panama in 1903 and continuing as late as 1952, when Colombia relinquished to Venezuela a claim to the Monjes Archipelago near the tip of the Guajira Peninsula. The complaint of the military officers included a plea that the earlier losses not be followed by relinquishing claims to the seabed in the Gulf of Venezuela, an area of potential petroleum wealth. Between fifty and 100 miles wide at its entrance (depending on the points between which the entrance line is drawn), the Gulf of Venezuela widens to a maximum of 120 miles. The shores of the gulf are entirely in Venezuelan territory except in the northwest, where they extend for a short distance along the coast of the Guajira Peninsula. Venezuela has traditionally held the position that the gulf is an inland body of water under its jurisdiction and has defined its entrance as a line extending eastward from the border point between the two countries on the Guajira Peninsula to the northern extremity of Venezuela's Paraguana Peninsula. Colombia, however, has claimed the waters offshore from its portion of the coastline to the midpoint of the gulf, an arrangement that would give it a triangular sector claimed also by Venezuela. Discussions concerning the conflicting claims were initiated in the mid-1960s; in 1970 the two governments agreed to specific negotiating procedures, and in mid-1975 the two presidents engaged in discussions that led to a draft agreement for settlement of the long conflict over the claims. The agreement was presented by the presidents to their political organizations early in 1976. Much of the frontier is located in sparsely populated and little developed regions, however, and border crossing by itinerant tradesmen, seasonal workers, and seminomadic tribal people are frequent. By far the most important of the border crossings have been those by migrants entering Venezuela without documentation in search of employment. In the early 1970s as many as 500,000 Colombians were believed to be residing illegally in Venezuela (see Land and People, this ch.). There was no corresponding movement of Venezuelan migrants into Colombia, but smugglers were reportedly saturating the markets in Colombian border towns with a variety of Venezuelan goods, electrical appliances in particular. In early 1976 a Bogota newspaper reported that the border town of Maicao on the Guajira Peninsula had a resident population of 35,000 and a transient population of about 10,000 smugglers at any given time. The illegal movement of goods into Colombia was offset by a substantial movement of Colombian cattle smuggled into Venezuela. Banking institutions on both sides of the frontier did a thriving business on the basis of this clandestine trade, which was believed to have a value many times that of all legal commerce. The principal internal political subdivisions are twenty-two departments and eight national territories, which include four sparsely populated intendencies (intendencias) and four commissaryships (comisarias) with still smaller populations (see fig. 1). These subdivisions are further divided into municipalities, consisting of administrative and commercial centers or municipal seats known as cabeceras surrounded by numerous specifically measured and individually named rural localities known as veredas. In Colombian statistical series the urban population includes residents of cabeceras, and the rural population includes residents of veredas. Departmental boundaries for the most part correspond to natural features. East-west departmental boundaries in eastern Colombia, for example, are marked by rivers; and boundaries in the Western Highlands for the most part follow watersheds. Certain political subdivisions have ethnic and historical significance. The department of Tolima, for example, corresponds generally to an area occupied by a nation of pre-Colombian Indians, the Panches; the department of La Guajira is the homeland of the Guajiro Indians. The internal political map, however, has been subject to frequent changes, usually through the carving of a new department or national territory out of an existing one. The department of Meta was formed from part of Cundinamarca, and the departments of Risaralda and Quindio were created from the department of Caldas. Changes in the political map have been radical as well as frequent-in 1910 the number of departments was reduced from thirty-four to fourteen; and during earlier years such considerations as lines of communication, economics, and social unity received little attention in determining the configuration and size of political subdivisions. The importance of these considerations has been recognized and has figured among the reasons for creating the new departments of La Guajira, Quindio, Cesar, Risaralda, and Bolivar. Natural Features Some 45 percent of the country is forested, about half of it in exploitable timber. Precipitous slopes and convoluted terrain in the highlands and the prevalence of swamplands and jungle at lower elevations limit the utilization of land; less than 3 percent of the national territory consists of farmland and, of this proportion, 13 percent is in permanent and seasonal crops, 53 percent is in pasture, 23 percent is fallow, and the remainder is forested or unused. Steeply sloping terrain, the composition of the soil, and heavy precipitation have made over 30 percent of the country highly susceptible to erosion; in an area equivalent in size to about one-fourth of all farmland, erosion is far advanced. A government official estimated in 1976 that 5 percent of the territory in the department of Cundinamarca had become so eroded as to be useless. The prevailing pattern of land use is one in which the more fertile flatlands tend to be devoted to commercial farming and cattle raising and smaller farm plots reach far up steep mountain sides. Land has been farmed successfully on plots with slopes of 50 percent or more. Soils vary radically in characteristics and fertility, and the complexity of the physical environment makes the matching of soils to climatic conditions difficult. The most productive soils are in the river valleys and the basins of the highland interior. Soils of the Atlantic Lowlands are generally superior to those of the Pacific coast, and the predominantly acid soils of the eastern plains are relatively infertile. Geographic Regions Geographers have devised different ways to divide Colombia into regions. The simplest is to see the country as consisting of three parts-a highland core, coastal lowlands to the west, and plains to the east. The plan is consistent with the pattern of the terrain, but the coastal lowlands of the Atlantic have characteristics very different from those of the Pacific. It is therefore appropriate to divide the country into four geographic regions: the Central Highlands, consisting of the three Andean ranges and intervening valley lowlands; the Atlantic Lowlands and the Pacific Lowlands coastal regions, separated by swamps at the base of the Isthmus of Panama; and eastern Colombia, the great plain that lies to the east of the Andes. Central Highlands Near the Ecuadorian frontier the Andes Mountains divide into three distinct chains, called cordilleras, that extend northwestward almost to the Caribbean Sea. Altitudes reach more than 19,000 feet, and mountain peaks are permanently covered with snow. The elevated basins and plateaus of these ranges have a moderate climate that provides pleasant living conditions and enables farmers in many places to harvest twice a year. Torrential rivers on the slopes of the mountains produce a large hydroelectric power potential and add their volume to the navigable rivers in the valleys. The great majority of the population lives in these mountainous regions where, before the appearance of the white man, Indians had developed a culture almost as complex and elaborate as that of the Incas to the south and the Aztecs to the north (see ch. 3). The three parallel chains of the Andes-the Cordillera Occidental in the west, the Cordillera Central, and the Cordillera Oriental in the east-present differing characteristics. In the Cordillera Oriental at elevations between 8,000 and 9,000 feet three large fertile basins and a number of small ones provide suitable areas for settlement and intensive economic production. In the basin of Cundinamarca, where the Spanish found the Chibchas-settled tribes of Indians practicing agriculture-the white invaders founded the town of Santa Fe (later Bogota) at an elevation of 8,660 feet above sea level. To the north of Bogota, on the densely populated plateaus of Chiquinquira and Boyaca, are fertile fields, rich mines, and large industrial establishments that produce a great part of the national wealth. Still farther north, where the Cordillera Oriental makes an abrupt turn to the northwest near the Venezuela border, the highest point of this range, the Sierra Nevada de Cocuy, rises to 18,310 feet above sea level. In the department of Santander the valleys on the western slopes are more spacious, and agriculture is intensive in the area around Bucaramanga. The nothernmost region of the range, around Cucuta and Ocana, is so rugged that historically it has been found easier to maintain communication and trasportation toward Venezuela from this area than toward the adjacent parts of Colombia. The Cordillera Central, also called the Cordillera del Quindio, is the loftiest of the mountain systems. Its crystalline rocks form a 500-mile-long towering wall dotted with snow-covered volcanoes. There are no plateaus in this range and no passes under 11,000 feet. The highest peak, the Nevado del Huila, reaches 18,865 feet above sea level. Toward its northern end this cordillera separates into several branches that descend toward the Caribbean coast. The Cordillera Occidental is separated from the Cordillera Central by the deep rift of the Cauca River valley; this range is the lowest and the least populated of the three and supports little economic activity. A pass about 5,000 feet above sea level provides the major city of Cali with an outlet to the Pacific Ocean. The relatively low elevation of the cordillera permits dense vegetation, which on the western slopes is truly tropical. The two rivers that separate the lines of the Andean trident have formed fertile floodplains in valleys that reach deep into the highlands. The Magdalena River rises near a point some 110 miles north of Ecuador where the Cordillera Oriental and the Cordillera Central diverge. Its spacious drainage area is fed by numerous mountain torrents originating high in the snowfields, where for millennia glaciers have planed the surface of folded and stratified rocks. The Magdalena is navigable from the Caribbean Sea as far as the town of Neiva, deep in the interior, but is interrupted midway by rapids at the town of Honda. The valley floor is very deep; nearly 500 miles from the river's mouth the elevation is no more than about 1,000 feet. Running parallel to the Magdalena and separated from it by the Cordillera Central, the Cauca River has headwaters not far from those of the Magdalena, which it eventually joins in swamplands of the Atlantic region. The area known customarily as the Cauca Valley does not include all of the lands flanking the river. This tropical valley, a fertile sugar zone that includes the best farmland in the country, follows the course of the river for about 150 miles southward from a narrow gorge at about its midpoint near the town of Cartago. The cities of Cali and Palmira are situated on low terraces above the floodplain of the Cauca Valley. Atlantic Lowlands The Atlantic Lowlands consist of all of Colombia north of an imaginary line extending northeastward from the Gulf of Uraba to the Venezuelan frontier at the northern extremity of the Cordillera Oriental. The region corresponds generally to one often referred to by foreign writers as the Caribbean lowland or coastal plain; in Colombia, however, it is consistently identified as Atlantic rather than Caribbean. The semiarid Guajira Peninsula, in the extreme north, bears little resemblance to the rest of the region. In the southern part rises the Sierra Nevada de Santa Marta, an isolated mountain system with peaks reaching a height of over 19,000 feet and slopes generally too steep for cultivation. The Atlantic Lowlands region is in roughly the shape of a triangle, the longest side of which is the coastline. Most of the country's commerce moves through Barranquilla, Cartagena, Santa Marta, and the other ports located along this important coast. Beyond these cities are swamps, hidden streams, and shallow lakes that support banana and cotton plantations, countless small farms and, in higher places, cattle ranches. The coastal cities were the first places settled by the Spanish. The Atlantic region merges into and is connected with the Central Highlands through the two great river valleys. It is the second most important region, after the Central Highlands, in population and economic activity. Pacific Lowlands The Pacific Lowlands are a thinly populated region of jungle and swamp with considerable but little-exploited potential in minerals and other resources. Buenaventura is the only port of any size on the more than 800 miles of coastline. On the east the Pacific Lowlands are bounded by the Cordillera Occidental, from which run numerous streams. A majority of these streams flow westward to the Pacific, but the largest, the navigable Atrato River, flows northward to the Gulf of Uraba, a circumstance makes the river settlements accessible to the major Atlantic ports and commercially related primarily to the Atlantic Lowlands hinterland. To the west of the Atrato River rises the Serrania de Baudo, an isolated chain that occupies a large part of the coastal plain. Its highest elevation is less than 6,000 feet, and its vegetation resembles that of the surrounding tropical forest. The Atrato swamp-in Choco Department adjoining the Panama frontier-is a bottomless muck forty miles in width that for years has challenged engineers seeking to complete the Pan-American Highway. Except where the highway is interrupted by this stretch, known as the Tapon del Choco (Chocon Plug), and an adjoining swampland in southern Panama known as the Darien Gap, it reaches without interruption from Alaska to the Straits of Magellan. In 1976 it was anticipated that this final segment of the highway would be completed in perhaps another six years by rock filling and bridge construction. A second major transportation project under consideration involving Choco Department, for which various schemes had intermittently been proposed, was the construction of a second interoceanic canal by dredging the Atrato River and other streams and digging short access canals. Completion of either or both of these projects would do much to transform this somnolent region. Eastern Colombia The area east of the Andes includes about 270,000 square miles, or three-fifths of the country's total area, but Colombians refer to it almost as if it were an alien land. The entire area is known as the Eastern plains. The Spanish term for plains (llanos) can be applied only to the open plains in the northern part where cattle raising is practiced, particularly in piedmont areas near the Cordillera Oriental. The subregion is unbroken by highlands except in Meta Department, where the Macarena Sierra, an outlier of the Andes, is of interest to scientists because its vegetation and wildlife are believed to be reminiscent of those that once existed throughout the Andes. The numerous large rivers of eastern Colombia include many that are navigable. The Guaviare River and the streams to its north flow eastward and drain into the basin of the Orinoco, the largest river in Venezuela. Those south of the Guaviare flow into the basin of the Amazon. The Guaviare serves as a border for five political subdivisions, and it divides eastern Colombia into the Eastern Plains subregion in the north and the Amazonas subregion in the south. In the south the plains give way to largely unexplored tropical jungle, where the scanty population becomes scantier still. Islands Colombia possesses a few islands in the Caribbean and some in the Pacific Ocean, the combined areas of which do not exceed twenty-five square miles. Off Nicaragua about 400 miles northwest of the Colombian coast, an archipelago of some thirteen small cays grouped around two larger islands forms the San Andres y Providencia Intendency. Other islands in the same area-the sovereignty of which has been in dispute-are the small islands, cays, or banks of Santa Catalina, Roncador, Quita Sueno, Serrana, and Serranilla. Off the coast south of Cartagena are several small islands, among them the islands of Rosario, San Bernardo, and Fuerte. The island of Malpelo lies in the Pacific Ocean about 270 miles west of Buenaventura. Nearer the coast a prison colony is located on Gorgona Island. Gorgonilla Cay is off its southern shore. Climate The striking variety in temperature and precipitation results principally from differences in elevation, and as a consequence the climate is frequently referred to as a vertical phenomenon. The country's proximity to the equator has the dual effect of widening the range of temperature from very hot at sea level to relatively cold at high elevations and of permitting little seasonal variation in temperature. At Bogota, for example, the average annual temperature is 58F, and the difference between the average of the coldest and the warmest months is less than 2F. More significant, however, is the daily variation in temperature, from 40F at night to 63F during the day. Colombians customarily describe their country in terms of the climatic zones: the area under 3,000 feet in elevation is called the hot zone (tierra caliente); elevations between 3,000 and 6,500 feet above sea level are the temperate zone (tierra templada); and elevations from 6,500 feet to approximately 10,000 feet constitute the cold or cool zone (tierra fria). The upper limit of the cold zone marks the tree line and the approximate limit of human habitation. The treeless regions adjacent to the cold zone and extending to approximately 15,000 feet are high, bleak areas (usually referred to as the paramos), above which begins the area of permanent snow (nevado). Vertical zoning has greater significance in terms of human settlement in Colombia than in any other country of Latin America. Almost 90 percent of the country's total area lies in the hot zone, where the full impact of the equatorial location is felt. Included in the hot zone and interrupting the temperate area of the Central Highlands is the long and narrow extension of the Magdalena Valley and a small extension in the Cauca Valley. Temperatures, depending on elevation, vary between 75F and 100F, and there are alternating dry and wet seasons corresponding to summer and winter respectively. Breezes on the Caribbean coast, however, reduce both heat and precipitation there. Hot zone rainfall is heaviest in the Pacific Lowlands and in portions of eastern Colombia, where rain is almost a daily occurrence and rain forests predominate. Precipitation exceeds 300 inches annually in most of the Pacific Lowlands; in eastern Colombia it decreases from 250 inches in portions of the Andean piedmont to 100 inches eastward. Extensive portions of the Atlantic interior are permanently flooded, more as a consequence of poor drainage than of the moderately heavy precipitation during the May through October rainy season. The temperate zone covers about 8 percent of the country, and in it lives about 40 percent of the population. This zone includes the lower slopes of the Cordillera Oriental and the Cordillera Central and most of the intermontane valleys. The important cities of Medellin (5,000 feet) and Cali (3,000 feet) are located in this zone, where rainfall is moderate and the mean annual temperature varies between 65F and 75F depending on the elevation. In the higher elevations of this zone farmers benefit from two wet and two dry seasons each year: January through March and July through September are the dry seasons. The cold or cool zone constitutes about 6 percent of the total area, including some of the most densely populated plateaus and terraces of the Colombian Andes; this zone supports about one-fourth of the country's total population. The mean temperature ranges between 50F and 65F, and the wet seasons occur in April and May and from September to December, as in the higher elevations of the temperate zone. Precipitation is moderate to heavy in most parts of the country, the heavier rainfall occurring in the low-lying hot zone. There are considerable variations because of local conditions that affect wind currents, however, and the low elevation of the Guajira Peninsula results in generally light rainfall; the annual rainfall of fourteen inches recorded at the Uribia station there is the lowest in Colombia. Considerable year-to-year variations have been recorded, and Colombia is not immune to droughts. A widespread drought that lasted from October 1972 into February 1973 caused a loss in crops estimated at 2.3 billion pesos (for value of the peso-see Glossary), or the equivalent of 5.2 percent of the 1972 gross national product (GNP). Vegetation Diversity of climate, elevation, and soils has resulted in a correspondingly great variety in flora, although an estimated 85 percent of the country's forest reserves are tropical trees. More than 7,000 species of plants have been identified. It has been estimated that a complete cataloging of the country's plant life would reveal twice this number. At high altitudes the soil of mountain meadows supports grasses, small herbaceous plants, and dense clumps of low bushes. In intermontane basins there are meadow grasses, willows, and a variety of bushes. Temperate levels support extensive and luxurious hardwood forests, ferns, and mosses. In the lowlands, where the vegetation varies with soil and rainfall, there are desertlike areas supporting only arid plants, deciduous forests, tropical rain forests, mangrove swamps, and grass plains. Forest trees include mahogany, pine, brazilwood, walnut, oak, and cedar. Planted eucalyptus groves are common; there are some 130 varieties of palm and about 700 varieties of wild orchid. Among the numerous forest products are cinchona, vanilla, gums, balsams, tanning agents and dyewoods, and vegetable ivory. Wild rubber grows in the Amazonas subregion and the Pacific Lowlands. Alfalfa has been planted in highland pastures, and in the lowlands a wide array of native and introduced grasses includes pangola, para, puntero, guinea grass, elephant grass, and bermuda grass. In addition the potential value as animal feed of at least twenty-six native tropical legumes has yet to be realized. Because of the climatic diversity and the advantage of a large variety of soils, Colombia is able to grow a great variety of food plants. The hot zone produces tropical and semitropical fruits; at higher elevations various cereals, vegetables, and fruits common in the United States are produced. Most of the original forest cover has been removed in the more heavily settled areas, and three has been considerable land erosion. In the mid-1970s Colombians were deforesting their country at the estimated rate of 2.5 million acres annually, and the National Forest Investigation Commission estimated that without reforestation 80 percent of the country's commercially exploitable timber would be exhausted in twenty-five years. In 1976, however, Colombia, with financial assistance from the International Bank for Reconstruction and Development (IBRD, also called the World Bank), had embarked on a five-year pilot reforestation project in the western part of the country. The focus was to be on planting pine, cyprus, and eucalyptus in a belt of land surrounding Medellin. Laurel trees were to be planted in the departments of Narino and Choco, and mangrove swamps along the Pacific shoreline were to be reforested by the companies exploiting them. Wildlife Climate, vegetation, and topography are reflected in the rich fauna of the country. Over 1,500 species of birds are known, including parakeets, hummingbirds, a broad spectrum of tropical birds including parrots, and quail. Many migratory birds winter in the area; as a result the bird population fluctuates according to the season. The extensive forests give shelter to large flesh-eating mammals, such as pumas, jaguars, and a wide selection of other cats, as well as racoons and carnivorous mammals of the musteline family. Bears, tapirs, peccaries, deer, otters, and tropical rodents are also abundant. In the jungles near the Orinoco and Amazon rivers, as well as near the coasts, there are sloths, anteaters, opossums, and a wide variety of monkeys. The capybara, known as the chiguero, is valued for its meat and its soft hide. Rivers and swamps are inhabited by several species of alligator and crocodile, including the small babilla (whose hide is sought by collectors), the caiman llanero of the eastern rivers, and the caiman negro. There are turtles, lizards, and iguanas. Boa constrictors thrive in the humid forests, and many other varieties of snake can be found. Among the more exotic wildlife are tiny frogs that exude from their skin a highly potent venom used for centuries by Indians in blowguns and of possible future medicinal use, monster earthworms that grow up to six feet in length, and birds with claws on their wings. The abundance of insect fauna is well established, but its composition has not been scientifically cataloged. An intensive study of malaria-carrying mosquitoes, however, has been in process for many years. Commercial fishing, 60 percent of it in freshwater species, is not well developed. Most commercial fishing is in the Magdalena River; some is in Atlantic and more recently in Pacific coastal waters. There is some fishing in swamps and in the rivers of eastern Colombia. Native freshwater fish carry such names as bocachica, dorado, and bagre, the last a kind of catfish. Eels can be found in the rivers, and some lakes are stocked with trout. The seafood catch remains far below its potential. The catch of shrimps in coastal waters is substantial and increasing, but spiny lobster production off the Guajira Peninsula and blue crab and tuna fishing in the Pacific coastal waters near Buenaventura could readily be increased. Mineral Resources Known mineral resources other than fossil fuels occur principally in the western highlands northeastward from near Cali to Cucuta near the Venezuelan border in an irregular oval zone about 400 miles long and 300 miles wide at the point of maximum width. Mineral deposits are particularly heavy within a 150-mile radius of the town of Honda on the Magdalena River northwest of Bogota. Only about 20 percent of the land in areas believed likely to contain deposits has been systematically investigated, however, and the full extent of Colombia's mineral wealth remains unknown. In addition a significant part of the known deposits represents only a potential asset until facilities for exploitation and transportation can be developed. Gold, first taken by placer mining in the major rivers, played an important role in determining early patterns of settlement and economic development. Since the early twentieth century it has been produced primarily from underground and secondarily from dredging operations. Three-fourths comes from the Antioquia Department and the balance from the departments of Caldas, Choco, Narino, Tolima, and Santander. Mines in Antioquia Department and to a lesser extent in the departments of Choco, Cauca, and Narino make the country the world's fifth largest source of platinum. Antioquia produces most of the country's silver, although deposits in Caldas and Tolima have also been worked. Iron ore deposits in Boyaca Department are exploited for use in nearby industrialized establishments with the help of fuels present in the same locality. Iron ore is also mined near Bogota and Medellin and occurs in the departments of Caldas, Huila, and Tolima. Since the nineteenth century copper deposits on the Guajira Peninsula have been known to exist, and copper has been discovered more recently in places in Antioquia Department. Nickel is found in Cordoba Department, and there are zinc deposits in Caldas, Cundinamarca, Narino, and Antioquia. Uranium mines are being developed in the departments of Huila and Santander, and there are antimony and bauxite reserves in various western departments. Extensive qualities of rock salt are recovered in the departments of Cundinamarca and Meta, and Caribbean lagoons are suitable for use as saltpans. White and amber mica occur in Cundinamarca, asbestos in Antioquia and Tolima, phosphorus in Norte de Santander, and calcite throughout eastern Colombia. Quarried minerals include marble, gypsum, sand and gravel; quartz crystals are produced in Boyaca. Other nonmetallic minerals include feldspar, phosphoric rock, sulfur, and dolomite. With the exception of moderate quantities of blue beryl, the only gemstones of importance produced are emeralds; these are claimed to be the world's finest, and Colombia is by far the world's largest producer. The mine at Muzo in the mountains in the western part of Boyaca Department and other mines in that general locality are the most important producers, although some emeralds have been taken from deposits in the department of Cundinamarca. The national government has a monopoly on the sale of emeralds. Colombian coal is not of high quality, but it is low in sulfur content, and there are extensive deposits in mountain and valley zones. Many of these valuable fuel deposits are reasonably near industrially valuable mineral reserves and other sources of raw materials. They occur near industrial centers and as a consequence can be used economically in spite of difficulties in transportation. As a result of the world energy shortage, the tempo of coal exploration and exploitation has accelerated. Coal deposits in the Central Highlands extend from near Cali in the south to Medellin in the north. Separated from this zone by the Magdalena River valley, a second belt of coal extends northeastward from near Bogota to the Venezuelan border. The newly discovered El Carrejon coal property in La Guajira Department was under development in the early 1970s and had known reserves of 80 million tons and probable reserves of as much as 200 million tons. The Ministry of Mines and Energy listed the country's known coal reserves at nearly 3.5 billion tons and additional probable reserves at more than 2.3 billion tons. Petroleum is tapped in the Cordillera Central and Cordillera Oriental from near Bogota northward along the arc of the mountains to the Venezuelan border near Cucuta. Farther north and east it is found in lowland areas. Offshore oil and gas wells have been drilled along the Atlantic coast, and in 1976 the long-standing dispute with Venezuela over possible offshore deposits in the Gulf of Venezuela appeared near settlement (see Boundaries and Political Subdivisions, this ch.) Petroleum production flagged during the 1960s and early 1970s, but in the mid-1970s it was hoped that the current output in Putumayo Intendency near the Ecuadorian border would be supplemented by production from newly discovered fields in that area.