A Delta Once More, A New Report: Documents Birds, Marine-Life, And Vegetation In The Colorado River Delta

The Environmental Defense Fund (EDF) today released new report, A Delta Once More, an important scientific analysis of life in the Colorado river delta since water has returned in the past two decades. The report details how water gets to the delta, and documents habitats and species living there.

Early naturalists and explorers observed the Colorado River delta as a maze of channels and lagoons teaming with vegetation, birds, fish and native people, in decisive contrast to Mexico’s Sonoran Desert, which surrounds the delta. As the demand for regular supplies of water increased in the West, dams began to pepper the Colorado River in the United States, upstream from the delta. Filling these dams depleted the delta of water, depriving plants and wildlife of essential water flows for years. Plants disappeared, and wildlife populations diminished.

“For years many scientists suspected that so little water was reaching the Colorado River delta that it was, in a sense, dead,” said Jennifer Pitt, a principle author of the report and policy analyst for EDF. The report is a collaborative effort by EDF, the Environmental Research Laboratory at the University of Arizona, the Technological Institute in Guaymas, Mexico, and the Sonoran Institute.

According to the report, there is enough fresh water reaching the delta to support a unique mix of life. “The Colorado River delta can be protected by a small amount of the river’s native flow,” said Ed Glenn, a biologist at the Environmental Research Laboratory. The delta is an important link in the Pacific flyway, providing winter habitat for migrating birds, and home to the Cucap