(adjective) Describes a species with only a single genetic or physical type and no officially recognized subspecies. While monotypic birds may still have subtle plumage or size variations, these differences are not sufficient to be distinguished as subspecies. Monotypic birds may still crossbreed with other species, though the hybrids are not independently recognized as a unique species or subspecies.
With nearly 10,000 bird species in the world, there are monotypic species found in every bird family. Detailed field guides may note monotypic birds so birders can more easily recognize hybrids or unusual variants, though it is more common to mention subspecies since many dedicated birders will note subspecies while listing. Examples of monotypic birds include the American avocet, bald eagle, Atlantic puffin, chimney swift and mountain bluebird.
Photo – Yellow-Headed Blackbird © Derek Bakken