The rice fields, which function as humidity, in the Vegas Atlas of the Guadiana, have modified the winter distribution habits of birds, according to research by the University of Extremadura, which has had the collaboration of the Guadiana Hydrographic Confederation, and which has been published in the journal Bird Conservation International.

The decline of wetlands has led to a considerable decrease in waterfowl in recent years. While there has been a growth in small reservoirs, next to rice fields, going from 25,277 between 1991 and 1994 to 46,136 birds in the period between 2007 and 2010, large irrigation reservoirs, built in the 60s, have seen their population figure reduced.

These recent reservoirs, Sierra Brava, Gargáligas, Cubilar and Ruecas, and the adjoining rice fields are home to more than 1% of duck species such as the European shoveler, pintail or teal, an area that according to the EU Birds Directive to designate a Wetland of International Importance, should become a Special Area of Conservation for Birds (SPA). according to the researchers responsible for the study.