This park has unmoving dunes and one moving dune, which is carried towards the interior by the southwesterly wind while the northeasterly wind moves it towards the coast. A plant species grows that is endemic to Galicia, Omphalodes littoralis, grows in the systems as do plants like the sea daffodil, which stores water in its bulb. Lake Carregal is connected to the Atlantic Ocean and is one of the most unusual ecosystems in the park, with a great variety of molluscs. Numerous waterbirds nest on Lake Vixán, such as the gadwall duck. One of the most unusual reptiles in this area is the western spadefoot, which has eyes with vertical pupils and only comes out at night. It is characterised by the black spades on its hind feet, which it uses to dig burrows in which to hide. Other protected species can also be found here, such as otters, turtles and lampreys.