The National Hunting Grounds of Mafra are an example of indigenous biodiversity, in other words, we can find in this area various native species of Portugal and of different ecosystems.

So far, almost 30 species of mammals, 70 species of birds, more than 20 species of amphibians, reptiles and macrofungi have been identified at the Hunting Grounds. And around 100 species of plants, among them trees and shrubs.

Among the group of mammals, we can find the smallest and most timid shrew, to the large herbivores such as the fallow deer and red deer.

Along the valley we can observe different trees growing close to each other, making the area denser and more humid. Of all the tree species the following stand out: ash, black poplar, plane trees, oak, and cork oak.

Associated with riverside ecosystems, or rather, with soils with a large quantity of water, they provide shelter for different species of animals such as birds and are extremely important as a source of food for large herbivores, particularly the oaks, given their abundance of leaves and fruit, in other words acorns.