Ornithofauna

(also avifauna), the aggregate of birds of a certain region or time period. An ornithofauna is understood to include the complex of bird species characteristic of any given zoogeographic subdivision, that is, a region or subregion. The principal zoogeographic subdivisions of dry land, which have retained their significance to this day, were established by the British scientist P. Sclater mainly on the basis of the distribution of birds. Present-day ornithofaunas in the northern hemisphere were evidently formed in the Pleistocene and later; those in the southern hemisphere were formed in the Pliocene. Within the complex of species that constitute an ornithofauna one differentiates nesting, resident, migratory, and wintering birds. The nesting and resident species are of the greatest importance in zoogeographic analysis.