Satellite view of the Purus-Madeira moist forests, Brazil Photograph by USGS   Northern South America: Northwestern Brazil Tropical and Subtropical Moist Broadleaf Forests   67,200 square miles (174,000 square kilometers) -- about the size of Washington Relatively Stable/Intact

· Flooding on the Flats
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Flooding on the Flats

Stretching east of the foothills of Brazil’s Carauari arch, an ancient zone of uplift, this ecoregion is almost entirely on the low Amazon basin and is almost uniformly flat. The landscape of these lowland plains are shaped by large meandering rivers, frequent oxbows, and thousands of tiny streams, all of which flood annually. The vegetation consists primarily of seasonally flooded tropical lowland rainforests.

Special Features

The Purus-Madeira moist forest region lies in the center of the Brazilian Amazon on the lowland plain separating the Purus and Madeira Rivers. This ecoregion is characterized by high biological diversity and endemism in both plants and animals. The region is almost entirely covered with evergreen tropical rain forest, with a tall canopy reaching 147 feet (45 m) high, and a well-developed and dense understory. In the southernmost portion, moist forests blend with patches of woodland savanna vegetation. This hot and humid region receives nearly 100 inches (2500 mm) of precipitation per year, and elevations range from 65 to 196 feet (20 to 60 m) above sea level.

	Five species of titi monkeys occur here, three of which are endemic. Because these primates have a hard time crossing large rivers, two distinct species may live on either side of a river and never come in contact with each other.

Wild Side

The animals here are very diverse and many are found nowhere else in the world. Mammals number about 160 species, 80 of which are bats. This ecoregion boasts over 570 bird species, including an abundance of seasonal migrants. Here, one might see a small group of endemic naked-eared squirrel monkeys crash through the leaves and branches, grabbing fruits and insects on the way. If a fruit is not quite ripe, the monkey will discard it--and tapirs on the ground below will eat them. A jaguar waits patiently for a group of white-lipped peccaries, rutting and digging among the leaf litter, to get close enough to pounce on. On the trunk of a palm-like Sohnreyia tree, a palm pit viper is poised for a strike as a tegus lizard approaches. A chestnut-fronted macaw clings to palm fronds as it reaches in to pluck ripe palm nuts. Nearby a toco toucan waits, content with whatever unripe fruit the macaw leaves behind. Purple flowers of a Physocalymma tree attract a great number of pollinators, including stingless bees, honey bees, bumble bees, and butterflies.

Cause for Concern

With the exception of the southern area, this ecoregion remains remarkably intact. Controlled and uncontrolled burning threatens the habitat in the southern part of this region. Cattle ranching, industrial-scale agricultural projects, and road building all threaten the fragile soils of this ecoregion.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.