The birds that nest, live or migrate through the Island. Some are quite abundant, others extremely rare, all these birds have become part of the natural heritage and biodiversity of this magnificent territory.
Birds that were intentionally or accidentally brought to the Island by man. They were mostly brought as pets, in cages, mostly from other parts of Africa, and theses have become quite successful and formed healthy reproductive populations.
We refer 12 subspecies present on the Island of Principe, though not exclusive - some are also present in Sao Tome. The concept of subspecies is fleeting, and it is indicated by significant morphological, behavioural and genetic differences between a certain species and its closest relative.
There are eight known endemic bird species exclusive to the Island of Principe. This is a remarkable number and it makes Principe the place in the world with more endemic bird species per square kilometre. This particular trait is the reason why most evolutionary biologists consider the Island to be a true natural laboratory for Natural Selection and for Evolution.
