Valle del Mara–—n, Peru Photograph by Michael Dillon   Western Peru, in the upper Marañon River valley. Tropical and Subtropical Dry Broadleaf Forests   4,400 square miles (11,400 square kilometers) -- about the size of Connecticut Critical/Endangered

· Mountains of Song
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Mountains of Song

Here in the lush Andes Mountains youâll find a feast for your ears. Visitors to these forests are treated to the songs of numerous warblers, thrushes, and other bird species. Listen carefully, though÷some of the calls you think are made by birds might be made by monkeys.

Special Features

Located at the meeting point between the central and northern Andes Mountains, this dry valley is almost entirely surrounded by lush mountain ranges. This relatively small ecoregion extends from the floor of the upper Marañon River Valley up to elevations of 6,560 feet (2,000 m). Cactus-dominated desert scrub, dry forest, and gallery forest make up this dry tropical forest mosaic. In the open deciduous woodlands, scattered mesquite, acacia, ceiba, guabo quere, and Caesalpinia trees are interspersed with columnar cactuses. Along the rivers and streams, this scrub becomes more dense and less seasonal, often remaining green year round. At higher elevations, the dry scrub gives way to grass and thorny shrubs before becoming montane forest.

	The endemic Marañon crescent-chest bird is usually not seen, but heard. It remains concealed under dense cover while it sings its melodious cho-cho-cho-cho song.

Wild Side

In the mesquite bushes you might find an endemic Marañon spinetail bird flicking its shaggy-looking tail as it chases small insects. Nearby, an endemic Marañon thrush might be seen perching on a high acacia branch, watching out for a South American fox. A flowering Caesalpinia tree attracts numerous hummingbirds, including the purple-backed sunbeam, gray-bellied comet, and spot-throated hummingbird. Long-tailed weasels, which often make their homes in abandoned armadillo burrows, are just one of the mammal species found here. In the upper canopy, troops of brown capuchin monkeys rummage for fruits, seeds, and small prey. Smaller squirrel monkeys seek food in the large ceiba trees.

Cause for Concern

This ecoregion has been under cultivation for a long time, and much of the original dry and riparian forest has been lost. Agriculture (mostly of oil palms), cattle ranching, and logging are currently serious threats, and oil extraction is a potential problem. Hunting and collection for the pet trade (especially collection of the yellow-faced parrotlet) are also problematic.

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