The birds of the arribes Nature · Pereña de la Ribera, Vitigudino, Salamanca Image of Pereña de la Ribera, not of the place itself. The cliffs of the Duero host one of the greatest concentrations of cliff-nesting raptors in the peninsula: some 550 pairs of griffon vulture and 75 of Egyptian vulture recorded in 2005, and a score of pairs of black stork, 8% of the Spanish population. Photo: Tres1416 (Public domain) What to see and do in Pereña de la Ribera