What Is a Passerine?
A passerine is a perching bird in the formal scientific order Passeriformes. These are the most familiar, typical birds and the term can be applied to more than half the world's unique bird species, including all the classic songbirds, sparrows, and finches.
PASS-err-eyen or PASS-err-eeen
(It rhymes with "pass her mine" and "gas burr wine" or "pass her thing" and "mass fur bling.")
What Birds Are Passerines
The Passeriformes is the largest order of bird classification and includes more than half the world's different bird species, with more than 5,000 unique species classified as passerines. These birds are often inaccurately called songbirds, as not all of them are equally vocally adept and not all passerines have musical calls or songs. Most birds in this classification do share many characteristics, however, including:
- Small to medium body size with a generally upright relaxed posture when perched.
- Relatively vocal, including different calls and often, though not always, elaborate songs.
- Altricial chicks that need extensive parent care and nurturing after hatching.
- Relatively bright plumage colors or distinct markings.
- Unwebbed toes and feet equipped with distinct, though usually small, talons.
- Generally diurnal behavior and most active during daylight hours.
The most prominent characteristic shared by all passerine birds is the anisodactyl arrangement of toes. These birds have four toes: three facing forward and one backward, which allows the bird to easily cling to both horizontal and nearly vertical perches, including branches and tree trunks. These birds also have an adaptation in their legs that gives them extra strength for perching. In fact, the relaxed position of their feet and talons is to be clenched securely, so the birds are able to perch easily even when sleeping and will not lose their grip. It is this toe arrangement and gripping posture that makes all passerines "perching" birds.
In addition to using their toes for gripping perches, many passerines will use their feet for other purposes. Some birds will preen with their feet, others use their toes to hold seeds or nuts while they pry off shells to reach the nutritious meat. Many birds grip nesting material in their feet and will use their feet to rearrange and build nests. Some birds, most notably corvids, may even use their feet to grip twigs, sticks, or rocks to be used as rudimentary tools.
With more than half the world's birds classified as passerines, these birds are familiar to all birders. Species such as warblers, thrushes, tanagers, sparrows, thrashers, finches, jays, larks, tits, nuthatches, chickadees, Orioles, and wrens are all passerines.
Because there are so many birds that can be classified as passerines and they are so diverse, it can be easier to note which birds are not considered Passeriformes in order to better understand the differences between types. Birds that do not fit within this order include:
- Ducks, geese, swans, and similar waterfowl
- Woodpeckers and barbets
- Hawks, eagles, owls, falcons, and other birds of prey
- Kingfishers and rollers
- Nighthawks and nightjars
- Grouse, quail, turkeys, and pheasants
- Gulls and terns
- Penguins, auks, and puffins
- Flamingos, herons, ibises, egrets, and other wading birds
- Plovers, sandpipers, and similar shorebirds
- Rails, moorhens, coots, and similar pond-swimmers
- Swifts, swallows, and martins
- Parrots, macaws, parakeets, and budgerigars
- Albatrosses, shearwaters, skuas, petrels, and other seabirds
- Ostriches, emus, cassowaries, and other ratites
While some of these birds may share a few characteristics with the Passeriformes, none of them share every trait in order to be lumped into the same general classification. These are only a few examples of birds that do not belong to the passerines but demonstrate just how diverse worldwide avifauna can be.
Passerine Jizz and Bird Identification
Comparing the overall characteristics of each type of bird can help birders better understand which birds are passerines and which are not. This can help birders better identify the jizz of a bird and begin narrowing down the type of bird to a specific species. In many cases, the first step of that identification is to note whether or not the bird is a passerine. Once that is determined, individual traits can quickly pinpoint an exact bird species.
Also Known As
Passeriform Bird, passerine Bird, perching Birds, and songbirds