Knowledge of landscape patterns and dynamics is essential for land use planners and natural resources managers. They need to know how landscapes have changed in order to determine the consequences and efficacy of the management policies and implement future decision-making. This study characterized the landscape of the Urdaibai Biosphere Reserve, which has been affected by the introduction of exotic tree species since the beginning of the 20^th century. We examined the dynamics of this landscape between 1991 and 2009 and the consequences of having been declared a UNESCO Biosphere Reserve in 1984. Most of the Urdaibai Biosphere Reserve potential vegetation (80%) is mixed-oak (Quercus robur L.) forest, but, currently, this forest is found in only 6.5% of the area. Most of the current vegetation (54%) comprises Pinus radiata and Eucalyptus sp. plantations. Over the period studied, land use had changed in only 11.8% of the area. Nearly 30% of the change was the replacement of traditional grasslands, crops, and heathlands by P. radiata and Eucalyptus sp. plantations. However, 22% of the change had reflected a recovery of the native vegetation, namely mixed-oak and Cantabrian evergreen-oak (Quercus ilex subsp. Ilex) forest, coastal sandy areas, or broad-leaf plantations. This recovery of the native vegetation has countered the tendency towards landscape degradation observed since 1957. Thus, despite the small change described, the first effects of conservation and environmental recovery policies can be detected. Nevertheless, there remains much to be done for recovering the natural ecosystem; the most difficult obstacles include the fact that most of the land is privately owned and an existence of the administrative complexity gives rise to problems that exist between different Administrations.