Once-dying Mexican river delta slowly nursed back to life

On a stretch of the Colorado River, which on the Mexican side of the frontier is mostly a dry riverbed, native cottonwood and willow trees have been planted in place of invasive shrubs. It is the fruit of two decades of work by environmentalists along the lower part of the river from the US-Mexican border to the upper estuary of the Gulf of California, also known as the Sea of Cortez. "If we give a little water and care to certain sections of the river, we can recover environments that had already been completely lost," said Enrique Villegas...