The Madre de Dios River

"The day has passed delightfully. Delight itself, however, is a weak term to express the feelings of a naturalist who, for the first time, has wandered by himself in a [South American rainforest]. To a person fond of natural history, such a day brings with it a deeper pleasure than he can hope to experience again."

Charles Darwin

Tropical rainforests are the richest land based environments on the planet. They exist on less than 7% of the worlds surface and yet provide habitat for more than 50% of all the worlds species. This includes plants, mammals, reptiles, insects, etc. The Madre De Dios region, which includes the Manu River and its biological reserve, Manu National Park is the most diverse piece of the Amazonian pie. This pristine tract of land, roughly the size of southern New England, on the western edge of the Amazon Basin where it runs into the Andes Mountains, supports over 1000 species of birds. One tenth of the worlds bird species exist here. Compare this with 800 total species in all of North America. More than 200 mammal species can be found as well as 1200 species of butterfly. Scientists estimate that almost half of all insects existing in rainforests are still unknown. Plants are another important resource of which we know very little. Many have yet to be recognized and named while those that are known are still, in many cases, not understood. 25% of all known drugs and medicines are derived from rainforest plants and yet of those Amazon Basin plants known to science, less than 5% have been chemically analyzed or otherwise studied.
Manu Wildlife Center

The history of the Madre De Dios region is very much a reflection of the topography within which it is situated. A jungle covered divide of hills to the north, the Andes Mountains to the west, and impassable rapids on the majority of rivers to the south and east, left large portions of the Madre De Dios watershed relatively untouched from the time of the spanish conquest.
In 1567, an expedition led by Juan Alvarez Maldonado trekked east from Cuzco and after 37 hard days of bushwacking, arrived on the Madre De Dios River. Ceremonies were performed proclaiming Spanish sovereignty over the entire river system and a group of his men were dispatched to continue explorations downstream while Maldonado returned to Cuzco to report. The second team continued on downstream, stopping at the confluence of the Manu River where ceremonies were again performed. Most of this group however, never made it back to Cuzco and the expedition did little to open up the area. In 1968, due largely to the efforts of naturalist Celestino Kalinowski, the entire Manu watershed was declared a reserve and all logging and commercial hunting was stopped. Kalinowski, who spent a great deal of time during the 1950's and 60's exploring the Madre De Dios and Manu river systems, did more than any other individual to bring to the attention of Peru and the rest of the world, the beauty and value of the area. The reserve was upgraded to a national park in 1973, and in 1987 the International Union for the Conservation of Nature (IUCN) declared it a world heritage site.

These Side Neck Turtles enjoy a sunny afternoon basking on a log in the river. Protected by most predators aside from man, these turtles feed on aquatic vegetation. Turtles appeared on the planet 300 million years ago and have undergone relatively little change since. Side Neck Turtles get their name because they must bend their neck sideways when withdrawing their heads into the protection of the shell.
During clear sunny days, turtles offer an example of symbiotic relationships, which are so prevalent in areas of high species diversity. Butterflies, attracted by the presence of turtles, will flutter above them while a few take turns landing and feeding on the salty juices which are produced in the nose and eyes. They, in return, help keep the eyes and nose of the turtles clear.

Relatively small but abundant, the White Caiman is one of three species which inhabit the Madre De Dios region. Adults grow to about six and a half feet and feed on a variety of fish and amphibians. They are common along the river and can often be seen basking in the sun but will usually flush to the water before being too closely approached. Their preferred habitat is at the edge of rivers and streams.
Smallest of the three is Schneider's Dwarf Caiman which is rarely seen because it lives beneath the closed canopy of small forest streams. Full grown they are only three feet long and are identified by the set of double scutes which project laterally from the tail.

Black Caiman can grow to lengths of twenty feet and more. They enjoy the rich, peaceful waters of oxbow lakes and feed on fish,amphibians, and occasionally an unwary mammal. They are known to feed on Capybara, Deer, and other mammals which unwittingly stray too close while drinking at the water's edge.

The Capybara is the worlds largest living rodent. They can weigh almost 150 pounds and are known to travel in heards of several dozen, though family groups of two to six are far more common in the rainforest.

Capybara are Diurnal animals, which means they can be active day or night. They feed on aquatic and semi-aquatic vegetation along river banks and oxbow lake edges. Always found near water, they will plunge in when alarmed and swim beneath the surface to escape.
Unfortunately, they are prized for their meat and have been overhunted in many areas. The inaccessability of much of the region, along with the protected areas of Manu National Park, have served to keep populations along the Madre De Dios intact.

The Rhinoceros Beetles is one of the species which inhabit every nook in the tropical world. Individuality among beetles is no surprise, they are one of the most diverse and populous families on the planet. In fact, Beetles account for 40 percent of all known species of insects, spiders,and other arthropods. Terry Erwin, a naturalist from the U.S. National Museum of Natural History, has estimated through sampling that 18,000 beetle species exist on 1 hectare (2.5 acres) of Panamanian rainforest. Compare this with only 24,000 known species in all of the United States and Canada.

Peru holds the world's bird volume record, supporting more than 1800 individual species. Almost a thousand species of birds are known to exist in the isolated region along the Madre De Dios and Manu Rivers alone, or about 10% 0f all birds in the world. Many of these species are considered endemic, meaning they exist nowhere else in the world. In addition, many species have adapted to such specific niches in the environment that they exist in very small territories, making the ecosystem extremely fragile. Great efforts will be required to ensure the regions continued vitality.

The Capped Heron is 22-24 inches in length, with cobalt blue facial skin, a grey blue bill, and gray legs. They have a black crown and white forehead, the rest of the plumage being entirely white.
Herons and Bitterns, part of the same family, are characterized by long legs, long necks, and usually a straight pointed bill.
Most are found in or near water, where they stand or wade in the shallows, preying upon fish and other aquatic organisms.
Herons generally roost and nest together, often in mixed species groups. A communal nesting site is called a Heronry.

The Spectacled Owl is the largest Owl species along the Madre De Dios River.
This Juvenile became a local resident at the Manu Wildlife Center. While around dinner it would perch near the dining room where it received the occasional scrap, it spent most of its time learning to forage for itself in the surrounding forest.
Wild animals, kept as pets, was a common occurence at the majority of small villages up and down the river. We saw many birds and mammals in the care of river communities.

There seven species of Macaw which inhabit the forests of the Madre De Dios river system.

Blue and Yellow
Military
Scarlet
Red and Green
Chestnut Fronted
Red Bellied
Blue Headed


Macaws feed on a variety of seeds,fruits, leaves, flowers,and nectar. Pairs of all species mate for life. One fascinating aspect of their lives is the daily congregation at specific, exposed portions of river bank where they eat mineral clays to to supplement their diet. Clay licks play an important role in the lives of many of the forests herbivors.

When travelling to new places or through new environments, the more knowledge you have the better off you are. Reading is a great way to prepare yourself. Presented here is a short list of books which should help introduce you to the Madre De Dios region as well as offer information about Peru, and Amazonian rainforest in general. This list is by no means complete, but stands as an adequate introduction to people, culture, wildlife, and ecology in Peru's southern jungle.

Emmons, L.H. 1990. Neotropical Rainforest Mammals. Chicago: The University of Chicago Press.

Macquerrie, K. 1992. El Paraiso Amazonico Del Peru: Manu Parque Nacional Y Reserva De La Biosfera. Barcelona: Francis O. Patthey and Sons.

Wilson, E.O. 1992. The Diversity of Life. Cambridge, Massachusetts: The Belknap Press of Harvard University Press.

Hilty, S.L., and Brown, W.L. 1986. A Guide to the Birds of Colombia. Princeton: Princeton University Press.

Terborgh, J. 1992. Diversity and the Tropical Rain Forest. New York: Scientific American Library.

Rachowiecki, R. 1996.Peru: a Lonely Planet Travel Survival Kit. Hawthorn, Austrialia: Lonely Planet Publications.