Peregrine Falcon

Powerful and fast-flying, the Peregrine Falcon hunts medium-sized birds, dropping down on them from high above in a spectacular stoop. They were virtually eradicated from eastern North America by pesticide poisoning in the middle 20th century. After significant recovery efforts, Peregrine Falcon has made an incredible rebound and is now a regular sight in many large cities and coastal habitats.

Measurements (Both Sexes)

Length: 14.2–19.3 in 36–49 cm
Wingspan: 39.4–43.3 in 100–110 cm
Weight: 18.7–56.4 oz 530–1600 g

Size & Shape

Peregrine Falcons are the largest falcon over most of the continent, with long, pointed wings and a long tail. Be sure to look at shape as well as size—long primary feathers give the Peregrine a long-winged shape. As with most raptors, males are smaller than females, so Peregrines can overlap with large female Merlins or small male Gyrfalcons.

Color Pattern

Adults are blue-gray above with barred underparts and a dark head with thick sideburns. Juveniles are heavily marked, with vertical streaks instead of horizontal bars on the breast. Despite considerable age-related and geographic variation, an overall steely, barred look remains.


Other Names

Duck Hawk
Faucon pèlerin (French)
Halcón peregrino (Spanish)

Behavior

Peregrine Falcons catch medium-sized birds in the air with swift, spectacular dives, called stoops.
In cities they are masterful at catching pigeons. Elsewhere they feed especially on shorebirds and ducks.
They often sit on high perches, waiting for the right opportunity to make their aerial assault.

Peregrine Falcons are very strong fliers and often reported to be the fastest bird in the world.
Their average cruising flight speed is 24 to 33 mph, increasing to 67 mph when in pursuit of prey.
When stooping, or dropping on prey with their wings closed, it's been calculated that Peregrine Falcons can achieve speeds of 238 mph.
On researcher studied trained Peregrine Falcons while skydiving and described their body position while diving at 150 mph and 200 mph.
When hunting, Peregrines start by watching from a high perch or by flapping slowly or soaring at great height.
Stoops begin 300–3,000 feet above their prey and end either by grabbing the prey or by striking it with the feet hard enough to stun or kill it.
They then catch the bird and bite through the neck to kill it. Peregrine Falcons do have other hunting methods,
including level pursuit, picking birds out of large flocks, and occasionally even hunting on the ground.
Though the Peregrine Falcon is an elite predator, it does have its own predators, including Gyrfalcons, eagles, Great Horned owls, and other Peregrines.

Habitat

Look for Peregrine Falcons perching or nesting on skyscrapers, water towers, cliffs, power pylons, and other tall structures.
If a mudflat full of shorebirds and ducks suddenly erupts from the ground, scan the skies. A Peregrine (or Merlin) is probably in the area.
Peregrines can be seen all over North America, but they are more common along coasts.

In North America they breed in open landscapes with cliffs (or skyscrapers) for nest sites. They can be found up to about 12,000 feet,
as well as along rivers and coastlines or in cities, where the local Rock Pigeon populations offer a reliable food supply.
In migration and winter you can find Peregrine Falcons in nearly any open habitat, but with a greater
likelihood along barrier islands, mudflats, coastlines, lake edges, and mountain chains.

Cool Facts

The name "peregrine" means wanderer, and the Peregrine Falcon has one of the longest migrations of any North American bird. Tundra-nesting falcons winter in South America, and may move 25,000 km (15,500 mi) in a year. Maps of the migration of individual falcons determined by satellite telemetry can be seen at Environment Canada.
People have trained falcons for hunting for over a thousand years, and the Peregrine Falcon was always one of the most prized birds. Efforts to breed the Peregrine in captivity and reestablish populations depleted during the DDT years were greatly assisted by the existence of methods of handling captive falcons developed by falconers.
The Peregrine Falcon is a very fast flier, averaging 40-55 km/h (25-34 mph) in traveling flight, and reaching speeds up to 112 km/h (69 mph) in direct pursuit of prey. During its spectacular hunting stoop from heights of over 1 km (0.62 mi), the peregrine may reach speeds of 320 km/h (200 mph) as it drops toward its prey.
The Peregrine Falcon is one of the most widespread birds in the world. It is found on all continents except Antarctica, and on many oceanic islands.

Food

Peregrine Falcons eat mostly birds, of an enormous variety—450 North American species have been documented as prey, and the number worldwide may be as many as 2,000 species. They have been observed killing birds as large as a Sandhill Crane, as small as a hummingbird, and as elusive as a White-throated Swift. Typical prey include shorebirds, ptarmigan, ducks, grebes, gulls, storm-petrels, pigeons, and songbirds including jays, thrushes, longspurs, buntings, larks, waxwings, and starlings. Peregrine Falcons also eat substantial numbers of bats. They occasionally pirate prey, including fish and rodents, from other raptors.

Nesting Facts

Clutch Size: 2–5 eggs
Number of Broods: 1 broods
Egg Length: 2–2 in 5–5.2 cm
Egg Width: 1.6–1.9 in 4–4.7 cm
Incubation Period: 29–32 days
Nestling Period: 35–42 days
Egg Description: Pale creamy to brownish, dotted or blotched with brown, red, or purple.
Condition at Hatching:  Helpless, covered in whitish down, with eyes closed, weighing about 1.5 ounces.

Nest Description

Males typically select a few possible nest ledges at the beginning of each season and the female chooses from these. The birds do no nest building beyond a ritualized scraping of the nest ledge to create a depression in the sand, gravel or other substrate of the nest site. Scrapes are about 9 inches in diameter and 2 inches deep.

Nest Placement

Typically, Peregrine Falcons nest on cliffs from about 25–1,300 feet high (and higher, including on the rim of the Grand Canyon). On these cliffs they choose a ledge that is typically around a third of the way down the cliff face. Other sites include electricity transmission towers, quarries, silos, skyscrapers, churches, and bridges. In places without cliffs, Peregrines may use abandoned Common Raven, Bald Eagle, Osprey, Red-tailed Hawk, or cormorant nests. In the Pacific Northwest they may nest among or under Sitka spruce tree roots on steep slopes.