Colorado River Delta

In northwestern Mexico, the Colorado River Delta was once a vast desert estuary where river flow and Gulf tides created braided channels, lagoons, mudflats, and marshes. Before twentieth-century dams, the river carried silt from the Rocky Mountains to the sea, sustaining about 7,810 square kilometers of wetlands rich in wildlife and long inhabited by the Cucapá, who farmed and harvested wild grain on the floodplain. Spanish contact began in 1540. Upstream dams and water diversion later cut off freshwater, shrinking wetlands to about 5 percent of their former extent and transforming the floodplain. Despite this decline, the delta remains ecologically important and now includes protected reserve lands and wetlands.

Mexico