La Tancada lagoon is one of the coastal lagoons of the Ebro delta which, with an area of ​​around 250 hectares, constitutes a very rich natural environment, both due to the presence of birds and fish. La Tancada has two buckets of similar sizes and of little depth (less than 70 cm). As for the fauna, it is an important space for the wintering of the coot (Fulica atra), the feathered goby (Podiceps cristatus), the alena's beak (Recurvirostra avosetta) and several anatids. Flamingos (Phoenicopterus ruber) and barn owls (Ardea cinerea) often move there in search of food. In the area, species such as the common plover, the tern (Sterna nilotica), the red shrimp (Tringa totanus), the green-necked duck (Anas platyrhynchos), the common coot (Fulica atra), the feathered gobbler ( Podiceps cristatus), the long-legged (Himantopus himantopus) and the common tern (Sterna hirundo).