A swallow with a forked tail, blue and burgundy head, and red-beige underside, flying.
An acrobatic Barn Swallow in the skies above Nepal. Photo by Deepak Budhathoki / Macaulay Library.

Our planet has a bounty of birds—more than 11,000 species in all. But on a global scale, most have relatively small ranges. And only a few dozen species can be called “cosmopolitan,” with ranges that touch six continents or at least three oceans. These are the birds that tie our human world together—birds that nearly all of us have in common.

The Barn Swallow at the top of this page is one of the best examples: a bird weighing less than an ounce, whose migratory routes touch Canada, Tierra del Fuego, Norway, Namibia, Russia, Australia, and most places in between. Their gleaming colors and graceful aerobatics delight birdwatchers on every continent save Antarctica.

Follow us on a tour of our favorite cosmopolitan birds—whether over land, in cities and towns, or out at sea.

The Birds of six continents

The birds We Bring With Us

With their seemingly inexhaustible talent for flight, birds are inherently good at finding new places to live (see the Western Cattle Egret below for a good example). But some species get a helping hand from humans. Some, like Rock Pigeons and House Sparrows, formed a bond with humans centuries ago and have followed us around ever since. Others are brought along for a variety of reasons—parrots and parakeets come with us as pets, for instance—but may escape or be released and gain a toehold on a new continent.

ocean Travelers

A white bird with pale gray wings, black cap, and little red feet and a red, pointed bill, stands on the ice.A white bird with pale gray wings, black cap, and little red feet and a red, pointed bill, stands on the ice.
Arctic Tern: Superstar Cosmopolitan. These champion migrators fly from the Arctic to Antarctica back—25,000 miles per year. When it’s time to molt, they sit on a patch of pack ice while they regrow their feathers, then keep going. Photo (Finland) by Matti Rekilä / Macaulay Library.

Oceans cover more than two-thirds of the planet, and birds have evolved to exist across most of that endless blue-gray habitat. The Arctic Tern is famous for covering a distance equal to the circumference of the Earth every year. With a lifespan that can exceed 30 years, an Arctic Tern might travel three-quarters of a million miles in its lifetime. Plenty of other seabirds have the ability to spend years on the wing, without touching land—following are a few examples of species that touch at least three of the world’s five oceans in their travels.

Honorable Mentions

Moon-faced brown, beige and chocolate bird with yellow eyes, flies towards the camera.Moon-faced brown, beige and chocolate bird with yellow eyes, flies towards the camera.
The Short-eared Owl is almost a cosmopolitan species. Its range doesn’t quite reach Australia, though it has managed to colonize several oceanic islands including Hawaii. Photo (Alaska) by Nathan Kelly / Macaulay Library.

The world is a big place, and some widespread bird species don’t quite make it to that sixth continent. Some species fall short through the vagaries of taxonomic changes—for instance the cosmopolitan species previously known as Cattle Egret was recently split into two species (Western and Eastern Cattle Egrets), neither of which make it to six continents. Others, like the Black-crowned Night-Heron, come oh-so-close to that sixth continent, but fall just short. We love them anyway: these are our honorable mentions.



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