It is the first Ornithological Reserve of Galicia y the biggest of all SEO/BirdLife bookings. With a total area of ​​7.534 hectares, it includes territories covered by various legal protection figures such as ZEC and ZEPA -within the Natura 2000 Network-, Wetland of International Importance, Ramsar Wetland or Area of ​​Special Protection of Natural Values. It is also the first ornithological reserve that has marine environment and is home to such interesting species as the Balearic shearwater or the shag, as well as various ecosystems such as intermareacoastal lagoons, rocky coast or dunes and beaches that are breeding grounds for the Kentish Plover. also owns one of the most important wetlands de Galicia and Spain for hosting 13.000 waterfowl of 220 species and where the spoonbill has an important winter refuge and migratory passage.