Hippo Pool (image) Cary Institute of Ecosystem Studies Share Print E-Mail Caption A hippo pool on the Kenyan reach of Africa's Mara River. These pools concentrate hippo waste that is flushed downriver during heavy rain events. Credit Christopher Dutton Usage Restrictions To promote this press release. Share Print E-Mail 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.