Spain's Doñana National Park is dying of thirst

The Doñana National Park in southern Spain is a UNESCO world heritage site. The park is the largest nature reserve for migratory birds in Europe. But this fragile ecosystem is under threat from illegal farms for the intensive production of red fruits. They need huge amounts of water for irrigation and are using up the park's groundwater. UNESCO is now threatening to withdraw the park from its list of world heritage sites, which would be a first for Europe. Our correspondents report.