Nature Park of Alvão the moist lands along the riverfront. The Olo River is rich in trout and is populated by the Eurasian otter ("Lutra lutra"). Throughout the region, bird populations are diverse and include nesting pairs of Golden eagles. Mammal populations are marked by the presence of Wild boar ("Sus scrofa"), Roe deer ("Capreolus capreolus"), European badger ("Meles meles"), Granada hare ("Lepus granatensis") and European rabbit ("Oryctolagus cuniculus"). Among reptiles in the area are the Iberian emerald lizard ("Lacerta schreiberi") and the Latastei viper ("Vipera latastei"). No less important to the region is the traditional architecture of the nature park region, especially in
Meles (genus) Primorskii. Genetic studies of mitochondrial DNA shows the separation of two variants on either side of the Volga but their exact taxonomic rank remains undefined. A further study of cheek teeth from individuals across the entire range supports this division and provides confirmation that "M. meles" and "M. anakuma" are indeed separate species. A further species is "Meles thorali" from the late Pleistocene, known only from fossil remains, specimens of which have been found at Saint-Vallier, Drôme, in southeastern France and Binagady, in Azerbaijan. These have large cheek teeth and characteristics intermediate between "M. meles" and "M. anakuma". It is