Falcons: The Fastest Birds on Earth – Complete Species Guide

Falcons are the sprinters of the bird world. No other group of birds of prey combines such slender wings, such a compact body, and such an explosive, straight-line pursuit. A Peregrine Falcon in a full vertical stoop is the fastest animal that has ever been measured, and even a small Merlin closing on a skylark brings a level of acceleration that few raptors can match. Falcons are also a genuinely distinct lineage — they are not small hawks, and a handful of anatomical details make the family unmistakable once you know them.

What Makes a Falcon a Falcon

Falcons belong to the genus Falco and its relatives, and they sit apart from the hawks, eagles, and kites. Four features do most of the work of separating them in the field or in the hand:

• Pointed, sickle-shaped wings. Where a hawk’s wing is broad and rounded, a falcon’s is narrow and tapered to a point. This reduces drag in fast flight and gives the rapid, stiff wingbeats that define falcon flight.
• The tomial tooth. A small, sharp notch on the cutting edge of the upper beak, unique among birds of prey. The falcon uses it to sever the neck of its prey, dislocating the vertebrae with a single bite — a method that dispatches dangerous prey safely and quickly.
• A long, narrow tail and short, compact body, producing a streamlined, torpedo-like profile in flight rather than the soaring “plank” of a buteo.
• Dark malar stripes or “moustaches” curving down from the eye on many species. These cheek marks are thought to reduce glare and to signal species or individual identity.

The tomial tooth is the most reliable single identifier if you have a bird in the hand, and it is the feature that tells you immediately you are dealing with a falcon rather than any hawk. For the side-by-side breakdown, see our guide to falcon versus hawk.

The Stoop: How Falcons Became the Fastest Birds on Earth

The falcon’s signature manoeuvre is the stoop — the bird folds its wings against its body into a teardrop and dives on prey from above. In this shape a Peregrine Falcon becomes an extraordinary aerodynamic object, and researchers using GPS and video have recorded dives at well over 380 km/h, making it the fastest measured animal on the planet. Specialised baffles in the nostrils deflect the rush of air so the bird can still breathe during the dive, and a third eyelid protects the eye at speed.

Not every falcon stoops in the grand vertical style. Gyrfalcons and Prairie Falcons stoop at shallower angles over open country, and the small falcons often press home a fast, low, level chase instead. But the anatomy — the pointed wing, the tight body, the powerful breast — is the same across the family and exists for one purpose: speed.

The Falcon Species of the World

Falcons are found on every continent except Antarctica. The table below sets out the species a global observer is most likely to encounter, with approximate adult wingspans.

The Large Falcons

The biggest falcons are powerful, cold-hardy birds of cliffs and open landscapes. The Gyrfalcon is the largest falcon in the world, an Arctic specialist that breeds on tundra cliffs and hunts ptarmigan, occasionally travelling far south in winter. It occurs in grey, white, and dark “morphs,” the white birds being the classic Arctic form.

The Peregrine Falcon is the best known falcon, a cliff-nesting bird originally of coastal and mountain crags that now also nests on city skyscrapers and bridges across the world. It is famed for the vertical stoop and for the sheer pace of its level pursuit.

The Prairie Falcon is the arid-country counterpart in western North America, a pale, warm-brown bird of dry cliffs and sagebrush that often hunts low and fast and takes ground squirrels and lizards as readily as birds.

The Small Falcons

The smaller falcons are no less impressive. The American Kestrel, at roughly 110 g, is the smallest North American falcon; it hunts insects and small mammals and is the only common North American falcon that habitually hovers while searching for prey. Its rufous tail and blue-grey wings make males unmistakable.

The Merlin is a compact, fast, dark falcon of moorland and open country, famous for low, relentless chases of small birds. The Eurasian Hobby is even more aerial in its habits, taking swallows, swifts, and large flying insects such as dragonflies on the wing during the northern summer. The Aplomado Falcon, a slim grey-and-rufous bird of Latin American savanna, occupies a similar niche in the neotropics.

Conservation

Falcons have been both victims and beneficiaries of the modern world. Their story is dominated by three threads:

• Pesticides. Organochlorines such as DDT thinned falcon eggshells and hit apex predators hardest. Peregrine populations collapsed across much of the world before the chemical was banned, and captive-breeding and release programmes — with the help of urban “eyries” on buildings — brought the species back. It is now a flagship conservation success.
• Habitat and disturbance. Cliff-nesting falcons are sensitive to human disturbance at nest sites, and the loss of wetlands and grassland affects their prey.
• Trade and persecution. Several falcons, especially the Gyrfalcon and the Saker Falcon, are affected by trapping for falconry and by illegal trade, while the Aplomado Falcon remains endangered within the United States.

Because falcons concentrate at migration bottlenecks and often winter in wetlands, they are among the most instructive raptors to watch. For the mechanics of such movements, see raptor migration explained.

Frequently Asked Questions

How fast is a Peregrine Falcon in a dive?

Recorded stoops the most reliable instruments have measured exceed 380 km/h, making it the fastest measured animal on Earth. In level cruising flight the same bird is far slower — typically in the range of 65–110 km/h — and the huge speeds come only from the vertical stoop, when the wings are folded and the bird is essentially free-falling in a teardrop shape.

What is a tomial tooth?

It is a sharp notch on the cutting edge of a falcon’s upper beak, unique among birds of prey. The falcon uses it to sever the cervical vertebrae of its prey with a single bite, dispatching animals that might otherwise injure it. It is one of the most reliable features for telling a falcon from an accipiter hawk.

Is a kestrel a falcon?

Yes. The American Kestrel is a true falcon in the genus Falco, the smallest in North America. It has the pointed wings, tomial tooth, and long-tailed streamlined profile of its larger relatives, but it is more insectivorous and much smaller than the Peregrine or Gyrfalcon.

How do falcons differ from hawks?

Falcons have pointed wings, long narrow tails, stiff rapid wingbeats, and a direct, fast flight; hawks have broader rounded wings, shorter or more fanned tails, and glide or soar more. The best structural clue is the wing shape, and the best tactile clue is the tomial tooth. See the full comparison in falcon versus hawk.

Where are the best places to see falcons?

Cliff and coastal sites are excellent in spring, and migration watchpoints and wetlands are best in autumn and winter. Peregrines now nest in many cities, so a downtown bridge or cathedral can provide a falcon without any travel at all. Learning the flight silhouette first, via our guide to identifying raptors in flight, makes every encounter more productive.

Continue with the Peregrine Falcon, the Gyrfalcon, the Merlin, or the American Kestrel.