These geographical and climatic conditions facilitate the introduction of exotic species that later turn to be invasive and destructive to the native habitats. More than 20% of the total number of extant species in continental Portugal are exotic. On Madeira, around 36% and on the Azores, around 70% are exotic. Due to this, Portugal was placed 168th globally out of 172 countries on the Forest Landscape Integrity Index in 2019.