The Biscayan Estuary
In the province of Biscay, between capes Matxitxaco and Ogoño, there is a 12-kilometre stretch of sandbanks that UNESCO has declared a world Biosphere Reserve (1984), along with many other ecosystems. Holm oak forests emerge just a few metres from the aquatic vegetation, giving an idea of the richness of the environment in which this estuary is located. One of its main attractions is the diversity of birds that inhabit it. You can learn all about them in the Urdaibai Bird Centre.
The Urdaibai Estuary is one of the most richly diverse natural landscapes in the Basque Country. Low altitude mountains with steep slopes give way to a valley that leads to the Cantabrian Sea, forming a wide estuary. The floodplain turns into marshland, while also shaping cliffs and beaches. This leads to the coexistence of a plethora of biotypes and ecosystems, including the wetland area that forms part of the Ramsar Convention and is a Special Protection Area for birds. The diversity of the area is reflected in the abundance of holm oak forests, bushes, heath, crags and aquatic plants. In the areas where man has intervened, forest plantations, pastures and crop fields can be found, which also form the habitat of other flora and fauna. It is home to more than 600 species, including the Cantabrian holm oak. In terms of fauna, the largest group is made up of birds, as this wetland is a stopping point for many migrating birds. Both sedentary and breeding avifauna form part of this ornithological richness. More than 300 vertebrates are catalogued in this Biosphere Reserve, but it is the European mink that stands out the most due to its scarcity in the Basque Country.
What you need to know
The world Biosphere Reserve covers, either partially or entirely, 22 municipalities. Town centres of great historical importance, villages and traditional hamlets dot the landscape.
In Urdaibai there is a coexistence of various interesting ecosystems, including the estuary, karst and a coastline formed by beaches and cliffs. Its Cantabrian holm oak is of great natural value. This diversity of biotypes makes for the perfect ecosystem for a wide range of birds, reptiles, fish, molluscs, etc. It is for this reason that the marshland area has been declared a Special Protection Area for birds, also forming part of the Ramsar Convention.
Information for visits
Biosphere Reserve Trust. From Bilbao, via the N-634 until the intersection with BI-635 that passes through the Reserve from south to north, between Amorebieta-Etxano and Bermeo. The BI-631 to the west links Mungia with Bermeo. Other local roads also pass through the area. Urdaibai Bird Center. It is about 4.5 kilometres from Gernika-Lumo. From there, take the motorway and head in the direction of Lekeitio until you reach the Kortezubi roundabout. Then, turn left, and continue for 700 metres until you arrive at the centre.