Copper Canyon, Mexico Photograph by David Olson   Southern North America: Western Mexico into the southwestern United States Tropical and Subtropical Coniferous Forests   About 86,000 square miles (222,700 square kilometers) -- about twice the size of Louisiana Critical/Endangered

· Golden Eagles Soaring Over Majestic Mountains
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Golden Eagles Soaring Over Majestic Mountains

The Sierra Madre Occidental Mountains extend from west-central Mexico northwards, gradually becoming isolated peaks surrounded by the Sonoran and Chihuahuan Deserts in southern Arizona. Steep slopes, deep canyons (Copper Canyon is the deepest in North America), and tall cliffs shape the majesty of these mountains. In the northern extremes of this region, isolated mountain peaks project upwards, forming "sky islands" of pine-oak habitat high above the dry desert floor. There is a great diversity in pine and oak forests, from the big Douglas fir and pine forests in the highest elevations to the oak-grasslands mosaics at the lowest elevations. Twenty-seven species of conifer trees and 21 oak species have been recorded in these mountains, making them a center of diversity for these groups of trees. More than 300 species of birds make their homes in here, including the golden eagle, endangered thick-billed parrot, military macaw, and tufted jay. The imperial woodpecker, an old-growth pine forest specialist, has not been seen in these forests in almost 40 years and is almost certainly extinct.

Special Features

The Sierra Madre Occidental pine oak forests are rich in endemic and endangered plant and animal species. Several species of oak and pine trees are found nowhere else. In the northern limits of the ecoregion, these "islands" of native oak forests protect an incredible number of animals, including over 85 species of reptiles (of which 22 are endemic), 20 amphibians (12 of them endemic), and a number of endemic birds, as well. In the northern portion, over 15 species of pine trees and more than 25 types of oaks occur.

	Thick-billed parrots once lived in the "sky islands" of southern Arizona, but they were hunted for the pet trade and "sport" so heavily that they no longer have permanent populations in the United States.

Wild Side

The Mexican wolf, American black bear, and jaguar once roamed large sections of the Sierra Madre Occidentals, but their ranges and populations have severely declined. Coati and cacomistles are still found here. The greatest diversity of squirrels in Mexico thrives in these pine-oak forests and is joined each year by thousands of migrating songbirds heading south from the colder areas of Canada and the U.S. to the warmer climates of Central and South America. Of the many birds in these forests -- woodpeckers, trogons, warblers, and eagles -- the rare endemic thick-billed parrot stands out as they fly in pairs, squawking and searching for pine nuts.

Cause for Concern

Logging of the pine-oak forests began in the late 1800s and continues to the present, leaving less than one percent of the original forest intact. Exploitation of dead trees for paper fabrication has driven the imperial woodpecker, which once used these trees for nesting and seed storage, to extinction. Many reptiles and insects have also become threatened as their habitats dwindle.

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