Wetlands

Portugal has a huge variety of wetlands, from large rivers like the Douro, Tagus and Guadiana, to the streams and springs of the interior, passing through lagoons, marshes, ponds, reservoirs and the transition areas between fresh and salt water, such as rias, estuaries and salt marshes. In many of them the water changes throughout the year: it floods in winter, dries up in summer, and the tides cause the boundary to vary every day in the estuaries and rias.

This diversity supports a very rich fauna, which lives in the water, on the banks and in the reed beds, rushes and riparian woods that surround them. As these habitats are interconnected, it is common to find the same species in various types of wetlands, and many birds use them as stopovers during migrations or as wintering grounds.

This chapter covers freshwater and brackish wetlands, namely rivers, streams, lakes, ponds, marshes, lagoons, reservoirs, estuaries, salt marshes, and salt pans, as well as the riparian forests that accompany them. The open sea and coastal areas exposed to the ocean are excluded and are dealt with in the coastal zone chapter. Streams and waterfalls that cross forests and mountains are also included in this chapter; however, they are also covered in the forest and mountain chapters, respectively. This chapter focuses mainly on the larger and more permanent stretches.