The largest wetland in the Middle East has shrunk by 90 percent since 1970, a change that has had a “devastating” impact on humans and wildlife, says the U.N. Environment Programme in a report to be released later this year. The UNEP says that dams and drainage projects have been the two main causes of the loss of the marshes, which used to cover 5,800 to 7,700 square miles where the Tigris and Euphrates rivers meet in southern Iraq. By May of last year, most of the wetland was barren, except for a small area on the Iran-Iraq border. Mammals and fish that lived exclusively in the marshlands are now considered extinct.