The familiar rock dove and mourning dove are members of the family Columbidae, order Columbiformes. Birds of this family are characterized by their small feet and head and their plump bodies with soft plumage. They are the only birds able to drink water with their heads down; all other birds must fill their mouth and tip their heads back to swallow. There are over 300 species, found everywhere except the polar regions; diversity is highest in the tropics, where there are plentiful supplies of the fruits and seeds on which the members of the family typically feed.
There are five species on the provincial bird list: two native, two introduced, and one recently extinct. The native species are the mourning dove (Zenaida macroura), whose long-tailed silhouette and soft gray-brown plumage, with its whistling wings and sobbing coo, are a familiar sight and sound in summer in the southern half of the province, along with the band-tailed pigeon (Columba fasciata). This western forest-edge bird, first seen in 1970, has been seen a few times since, mainly in townsites in the southern third of the province.
The extinct species is the passenger pigeon (Ectopistes migratorius), an eastern forest species which nested in the river valleys of the province. It was numbered in the millions when first encountered by European settlers. Hunting pressure and destruction of the hardwood forests in which it nested in colonies resulted in its extinction by the beginning of the 20th century. The introduced species are the rock dove (Columba livia) and the Eurasian collared dove (Streptopelia decaocto), an escaped cage-bird species. The multi-coloured domestic form of the rock dove is a common permanent resident in the southern half of the province, often to pest proportions. The collared dove has recently been recorded in the southern margins of the province, as an invasive species.