The tyrant flycatcher (family Tyrannidae) comprises a large, diverse New World family of birds. The name flycatcher also refers to some members of the Old World family Muscicapidae and to some other birds.

Tyrannidae range from robin to warbler-size. Many are dull olive green; some are strikingly coloured. All feed by capturing a flying insect and returning to a perch to eat it. They are the only representatives in Canada of the suboscine perching birds (ie, those without true songs), and their loud, abrupt calls are the easiest means of distinguishing many species in the field.

Of the 539 known species of Tyrannidae, 18 regularly breed in Canada (12 called flycatchers, 2 kingbirds, 2 pewees, 2 phoebes); 12 others stray here. Canadian Tyrannidae are present May-September, when insects are available.

The great crested flycatcher (Myiarchus crinitus) of eastern broad-leaved woodlands and olive-sided flycatcher (Contopus borealis) of coniferous forests across Canada are large compared with species of the genus Empidonax.

The yellow-bellied flycatcher (Empidonax flaviventris) of northern spruce forests, least flycatcher (E. minimus) of broad-leaved stands and alder flycatcher (E. alnorum) of alder and willow thickets are widespread from Newfoundland to the Yukon. Five others (E. oberholseri, E. hammondii, E. wrightii, E. occidentalis and E. difficilis) occur only in the West, and 2 southern species (E. virescens, E. traillii) breed only a short distance north of the US border.

The kingbirds are large, pugnacious flycatchers. Eastern kingbirds (Tyrannus tyrannus) breed from the Northwest Territories to Nova Scotia; western kingbirds (T. verticalis) are found in the southern prairies and southern BC.

Pewees are a little larger than Empidonax flycatchers. Eastern wood pewees (Contopus virens) breed in southern Canada from Manitoba to Nova Scotia. Western wood pewees (C. sordidulus) are found from southwest Manitoba to the southern Yukon, including coastal BC.

Phoebes are bluebird-sized. Eastern phoebes (Sayornis phoebe) are found from the southeastern Yukon across southern Ontario and southwestern Québec to New Brunswick. Say's phoebe (S. saya) breeds in the Northwest Territories, Yukon, BC, Alberta and southern Saskatchewan.