Grand Canyon Reach of the Colorado River (image) Cary Institute of Ecosystem Studies Caption The research team investigated food webs in the Grand Canyon Reach of the Colorado River. Credit Emma Rosi-Marshall Usage Restrictions To promote this release. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.