An aquatic paradise in Mexico pushed to the edge of extinction

Xochimilco, Mexico

WITH their grey-green waters and blue herons, the canals and island farms of Xochimilco in southern Mexico City are all that remain of the extensive network of shimmering waterways that so awed Spanish invaders when they arrived here 500 years ago.

But the fragility of this remnant of pre-Columbian life was revealed last month, when a 20-foot-deep hole opened in the canal bed, draining water and alarming hundreds of tour boat operators and farmers who depend on the waterways for a living.