Satellite view of the Balsas dry forests, Mexico Photograph by NASA   Southern North America: Southern Mexico Tropical and Subtropical Dry Broadleaf Forests   24,100 square miles (62,400 square kilometers) -- about the size of West Virginia Critical/Endangered

· Gila Monsters and Green Parakeets
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Gila Monsters and Green Parakeets

The Balsas Dry Forests ecoregion lies in the valley of the Balsas River and is bounded by the Trans-volcanic Belt to the North, the Sierra Madre del Sur to the South, and the highlands of Oaxaca to the east. Vegetation grows at altitudes of 660 to 3,300 feet (200 to 1,000 m) above sea level, in a tropical seasonal climate that has annual average rainfall of less than 47 inches (120 cm) per year. There is a long dry season that lasts from five to eight months. The tree species that thrive in this climate include several species of copal as well as the chupandia. In addition, one finds Ceiba parvifolia, Haematoxylon brasiletto, desert fern, and pajaro bobo. Cacti, such as species of Lemairocereus, Cephalocereus, and Mammilaria are also common. Animals that make their homes in the dry forests include the venomous gila monster and the noisy green parakeet.

Special Features

At least 24 of the 60 known species of Bursera trees grow in these forests. It is also the center of distribution for Leucaena species and the Commelinaceae and Fabaceae families. The largest guaje rojo tree is endemic here, as well as a large number of species including several cacti, acacias, and morning glories. Eleven of the swallowtail butterflies are endemic. It is a special region for two rarely seen bats: the California myotis and the long-legged myotis. Slaty and dwarf vireos, banded quail, and black-chested sparrows are some of the birds largely restricted to the Balsas region.

	The endangered jaguarundi, a medium-sized cat, is active both day and night. Its favorite foods are small rabbits, birds, and small rodents.

Wild Side

Birds nesting in this region include the banded quail, greater roadrunner, west Mexican chachalaca, crested guan, and orange-fronted parakeet. Occasionally, you might spot an ocelot, coati, jaguarundi, coyote, grey fox, or even a jaguar. However, all the wild cats are now endangered. One of the smallest creatures in the dry forests is the silky pocket mouse. The Balsas burrowing toad, the only representative of its family, occurs in the lower reaches of the Balsas River.

Cause for Concern

Some large tracts of dry forest still occur. However, in the state of Morelos, only 10 percent of the original forest cover is undisturbed. Agriculture and cattle farming cause the greatest loss of habitat. Illegal extraction and trade have reduced populations of both plant and animal species. Collared peccaries and white-tailed deer used to be seen frequently; they have since been over-hunted. Parakeets, macaws, and songbirds are sold illegally on domestic and international markets. Orchids and cacti are also traded illegally, and many are now endangered. Much greater protection of remaining forest is needed.

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