Among the numerous species of invertebrates there stand out two groups: snails (12 snail species have been classified) and crabs.
In the aquatic areas you can find fishes, amphibians and reptiles. There are eight species of fishes, but only the barbel, the nase and the eel are autochthonous. Among the amphibians there stand out the anuran and the newt and among the reptiles there are up to ten species, standing out a species of water tortoise named galapago leproso and different species of saurian and ophidians, standing out the viper vibora hocicuda.
Birds: it is important to emphasize that the Bardenas is the area of Navarra where most aquatic species stay in winter. As well as vultures, golden eagles, Egyptian vultures, golden owls and other predatory, it is important to point up the presence of steppe birds like larks (calandria, terrera común, collalba gris) and great bustards.
In the Bardenas Realses we can also find 28 different species of mammals. Eight of them are micromammals like shrews, the dormice, rats and nine species of bats. The remaining animals are hedgehogs, weasels, polecats, martens, badgers, foxes, wild cats, genets, rabbits, Iberian hares and wild boars.
The botanic interest of flora and fauna of the Bardenas Reales is related to the climatic singularity of the Ebro hollow. It figures in the Spanish Inventario Nacional de Hábitats (national inventory of habitats), elaborated under the protection of the directive 92/43, CEE, from the 21st of May.