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
European hedgehog days they can roll into a ball. Weaning occurs at four to six weeks of age. European hedgehogs may live to ten years of age, although the average life expectancy is three years. Starvation is the most common cause of death, usually occurring during hibernation. If alarmed, the animal will roll into a ball to protect itself. Many potential predators are repelled by its spines, but predation does occur. Remains of hedgehogs have been found in the stomachs of European badgers ("Meles meles"), red foxes ("Vulpes vulpes") and pine martens ("Martes martes"). A large portion of these may be from