View Map of the Peruvian Lower Amazon




Iquitos today is the most important port on the Upper Amazon and it serves as the starting point for all nature-oriented travel in the region. Capitol of the Departamento de Loreto, the city lies some 2300 miles upstream from the mouth of the Amazon and about 360 miles east of the Andes. The settlement rests on a floodplain about 40 feet above the high-water mark on the left (west) bank of the river, 400 feet above sea-level. Iquitos lies between two rivers: the Nanay to the north, and the Itaya to the south.

The inhabitants of the village called San Pablo de Napeanos del Alto Nanay moved, in 1757, to the spot that was to become Iquitos. The city reached its cultural peak during the latter part of the 19th century when the rubber boom caused an influx of wealth into the region; this endured until World War I. Indians of many tribes were forced into labor, and their efforts permitted the (mostly European) rubber barons to amass fortunes.

During this period, garish buildings were erected in Iquitos, and they were adorned with imported materials of several types. Colorful tiles from Valencia, Seville, and Lisbon covered exteriors, and many featured ironwork forged in Germany. The "Iron House" on today's Plaza de Armas was designed by the French engineer Eiffel, purchased by a rubber baron at the Paris World's Fair, disassembled, and brought to Iquitos. Today, it houses two restaurants. At one point, Iquitos became so opulent that a small railroad was constructed, running along the Amazon's left bank to what is now the central plaza.

The economy of Iquitos has traditionally been extractive. In its early days, wax and sarsaparilla were gathered for export. Following the slave market and rubber boom, rosewood, animal skins, live animals, timber, and presently petroleum have characterized exports.

A walk down the streets of Iquitos today shows her cultural diversity. Boras, Yaguas, Cocamas, Ticunas, and a host of other Amazonian tribes are represented. Peruvians from the coast and highlands as well as the interior forests are here also. There are citizens of Spanish and European descent, and even some Americans who live here. Population estimates fall between three and four hundred thousand. The city has a university and several cultural or academic institutions, and a recently opened library boasts an excellent collection of antiquarian books about the region. The region is accessible only by air and water, although the only road, between Iquitos and Nauta, is being paved at present. Iquitos is boisterous, friendly and colorful. Although cars are on the increase, the principal modes of travel are buses and three-wheeled motorcycles known as "moto-cars." The market and (seasonally) floating neighborhood of Belen are bursting with fruits and forest products, fishes of every kind imaginable, spices, peppers, and folk remedies. Open-air restaurants, parades and all-night dances (week-ends) are part of local life. The attitude is open and helpful, typical of the frontier: good humor and good will abound. The political problems that plagued other parts of Peru never found a receptive audience in Iquitos. Moreover, the region is ringed by five military garrisons and so isolated as to practically be its own country.



From its birthplace high in the frigid Andes, the mightiest river in the world twists and turns— implacable— controlling all life within its reach. Sluggish-- it scarcely falls 250 feet over most of its course--its power derives from the volume it carries. Everything is modified by the Amazon. During dry periods, the river exposes vast, sand beaches, and winds among myriad islets; during the rains, the river swells its crumbling banks, spilling over thousands of square miles of forest. The Amazon destroys, regularly chewing great hunks out of the banks and ferrying trees, houses, and inhabitants on its march to the sea. The Amazon builds, annually depositing rich loam and sediment that allows crops like rice and melons to flourish. Indeed, the life cycles of many trees depend on foraging fish during high waters: without their digestive processes, the seeds fail to germinate.

Originally a vast lake that emptied into the Pacific Ocean, the Amazon reversed its drainage to the Atlantic during the Pliocene uplift of the Andes. In the Pre-Cambrian era, the clinal formation over what is now the Amazon Basin collapsed, creating a shallow sea, and leaving only remnants of what was once a vast continent. Today we see its remnants: the Guyana Highlands and the Brazilian Plateau to either side of the river basin. Beginning in the Cretaceous, vast alluvial deposits from ancient and highly weathered rocks were washed into the water: these kaolins today characterize much of the region's soil. Owing to its origin, creatures like freshwater stingrays (Potamotrygon), and dolphins (Inia and Sotalia), characteristic of the Amazon and Orinoco, actually invaded from the Pacific. The Basin as it exists today is really a Pleistocene phenomenon, for it was during the Ice Age that its drainage pattern was formed. At this time, owing to the waxing and waning of glaciers, the Amazon Basin was alternately either forest or dry savanna.

Nearly 4000 miles in length, the Amazon today boasts over 1000 major tributaries, eight of which produce more water than the Mississippi, seven of which exceed 1000 miles in length, and one of which exceeds 2000 miles in length. The Basin courses through six countries and drains nearly 3,000,000 square miles, practically double that of its nearest rival. Quite simply, it is the greatest wilderness on earth. At its mouth, over 150 miles wide, the Amazon produces one-fifth of the world's freshwater; over six million cubic feet per second flow into the Atlantic. Ocean-going vessels can reach Iquitos, and the river is navigable for several hundred miles beyond that point.

Tributaries are often characterized as being either "blackwater" or "whitewater." The former flow over granitic layers and are somewhat sterile, their color owing to the tannins from leaves in the water. The latter are silty and sediment-rich, carrying minerals and abundant fish life. Most Andean rivers (and therefore much of the Upper Amazon Basin) are of the whitewater type, as is the Amazon itself. However, the distinction can be difficult to discern, especially when differing levels force water to back up for many miles from a large river over one of its tributaries.

The Amazon and its tributaries continually change courses, creating immense swamps and oxbow lakes ("cochas"). These comprise important habitat for many species of birds and fishes. But the region is far from just a swamp. The rainforest, as seen from the air, resembles little more than a single, albeit spectacular, carpet of green. However, it is comprised of many, distinct habitat types, each characterized by subtly-to-markedly different vegetation. The vast majority of land in the Amazon Basin lies above the mean high-water mark. Around Iquitos there are several major land types: seasonally flooded forest (including bajial, tahuampa, and purma), non-inundated upland forest (generally called "altura," and including monte alto, varrial), and palm swamp (aguajal; Mauritia flexuosa). Many habitat types remain undetected.

In the Iquitos region, water levels generally begin to climb in late November, accompanied by a marked increase in rainfall. Waters crest in late April or May, but much of their fluctuation is a product of rains in the Andean region. Over the course of a year, the Amazon may fluctuate as much as 50 feet, and its rise and fall are punctuated by brief, unpredictable reverses. The equatorial climate is surprisingly varied, and nights can be chilly, especially during June. Average temperature is about 80 degrees Fahrenheit, although the forest feels much cooler.



Despite the prodigious efforts of a cadre of botanists, the Upper Amazon region remains poorly known. Ecuador has at least 13,000 known plant species, and a sample of tree diversity in the Ecuadorean Amazon yielded in excess of 500 species. Colombia is known to harbor some 50,000 plant species, and that number can be expected to increase. The region is quite diverse, and the innumerable specialized habitats host distinct assemblages of trees and other plants. In general, epiphytes (orchids, bromeliads, aroid plants, ferns, etc.) Are less prominent in the Amazon Basin that in more elevated regions, but they are still an obvious component of the forest. Plants have played an integral role in human cultures in the Amazon, and today most woodsmen are surprisingly adept at species recognition. Of equal interest are the uses to which plants are put by people in the region.



The Amazon boasts the most diverse freshwater fish fauna in the world, with catfishes the predominant family. The rate of discovery of new species continues to be high.

Peru's bird fauna has not been adequately summarized, but it can be expected to rival Colombia, which has in the vicinity of 2000 species. Many of these are seasonal migrants to North America. Several dozen species of wading birds abound along the Amazon and its tributaries, and the area is rich in flycatcher species as well. It is easy to observe between 200 and 300 bird species during a one-week stay.

Mammals are also well represented, although much more difficult to observe. Bats predominate, with dozens of species, while marsupials are also diverse in the area. Large aquatic rodents like capybaras and pacas are common, and the Brazilian Tapir, South America's largest land mammal, is found throughout the region. There are six species of wild cat, two wild dogs, two species of dolphins, two deer, and innumerable rodents.

Reptiles and amphibians total over 360 species, perhaps the most diverse assemblage of these creatures in the world. Among the more obvious are the treefrogs, with nearly one hundred varieties, and the nearly fifty species of lizards. Snakes, which number nearly 90 species, are notoriously difficult to encounter, and most visitors to the region never manage to see one. In recent times, the South American River Turtle existed in enormous numbers. One of the largest freshwater turtles in the world, this reptile was over-exploited for its delicious meat and eggs. Today, it is endangered and seldom seen. Crocodilians include three species, all of which are fairly common in the area, plus one that is rare.

Insects in the Upper Amazon are too diverse to enumerate. The beetle and butterfly faunas are spectacular, and include some of the most beautiful butterflies (morphos) and the largest beetles in the world (Titanus giganteus).


Suggested Reading

In preparation for travel to the Peruvian Amazon, we recommend any of the following books: