The diversity of habitats to be found in URDAIBAI is reflected in the diversity of the area’s birds, mammals, amphibians, reptiles, insects, fish, molluscs and crustaceans.
The marshlands, where the tides meet the fresh water from the rivers and the springs that well up from the limestone and clay of the valley bottoms, provide an extremely valuable habitat for bird life. URDAIBAI is a stopping place for birds migrating between Europe and Africa, and the Basque Country’s richest enclave for bird life, be it sedentary, nesting, wintering or passing through. The area is on the RAMSAR Convention’s List of Wetlands of International Importance and is part of the NATURA 2000 network of European protected natural areas.
As well as birds, the area has a healthy presence of other animals such as the European mink (Musela lutreola) which is almost extinct elsewhere in the Basque Autonomous Community. In all, 318 species of vertebrates have been catalogued in URDAIBAI
