The peregrine falcon (Falco peregrinus) is renowned for its speed and aerial prowess. As the world’s fastest bird, peregrines have been clocked diving at speeds over 200 miles per hour. Their powerful talons and sharp beaks make them formidable predators capable of taking down prey much larger than themselves. But just how big do peregrines get? In this article, we’ll explore the typical size and dimensions of these remarkable raptors.
Average Weight
A full grown peregrine falcon weighs approximately 1 to 1.5 pounds on average. The females are noticeably larger than the males. A typical adult female peregrine will weigh around 1.5 pounds, while the smaller males weigh closer to 1 pound.
The peregrine’s compact, muscular body and long, tapered wings are perfectly adapted for speed and maneuverability in flight. Their lightweight build combined with tremendous power enables them to achieve their record high velocities when diving at prey.
Wingspan
The average wingspan of an adult peregrine falcon is between 39 and 43 inches. Again, females have a wider wingspan approaching the upper end of this range, while males are towards the lower end. The long, pointed wings of the peregrine allow it to cruise at fast speeds and make the nearly vertical stoops for which they are renowned. They can fold their wings tightly against their bodies to become more streamlined and reach even greater velocities during a dive.
| Peregrine Falcon Size | Female | Male |
|---|---|---|
| Weight | 1.5 lbs | 1 lb |
| Wingspan | 39 – 43 inches | 39 – 43 inches |
| Length | 19 – 24 inches | 15 – 20 inches |
Length
From head to tail, peregrines measure between 15 to 24 inches in length. The females are noticeably bigger than the males, measuring 19 to 24 inches compared to the males’ 15 to 20 inches. The peregrine’s tail itself accounts for 7 to 8 inches of their total length.
The peregrine’s compact body reduces drag during high speed chases and dives. Their broad shoulders and chest provide strength and power, while their tapered tail acts as a rudder to maneuver deftly through the air.
Other Physical Features
In addition to their compact build for speed and agility, peregrines possess many other physical features well-adapted for a predatory lifestyle:
– Hooked beak – The sharp, thick beak of the peregrine has a pronounced notch or hook at the end to rip and tear prey flesh.
– Strong legs and talons – A peregrine’s legs are short but very muscular. Their toes end in curved talons used for snatching birds out of the air and delivering a killing blow on impact. At high velocities, the force of these talons can be very powerful.
– Forward-facing eyes – The eyes of a peregrine falcon are positioned on either side of its head to provide excellent binocular vision focused forward for accurately spotting and pursuing prey while diving through the air.
– Dense feathers – The peregrine’s feathers are tightly packed and dense to protect it from impact injuries when it crashes into prey at high speeds. The feathers are thick but streamlined to maintain aerodynamic efficiency.
– Great hearing – Peregrines are adept hunters in large part due to their extremely acute sense of hearing. They can detect faint sounds of flapping or rustling feathers of birds and bats while flying at high altitudes.
Size Comparison to Other Birds
To better appreciate the peregrine falcon’s size, it helps to compare it relative to some other common bird species:
– Peregrine vs. pigeon – Rock pigeons are a common prey item for urban peregrines. Although plump pigeons can outweigh peregrines, the falcon is longer and has a greater wingspan.
– Peregrine vs. crow – American crows are as long as or longer than peregrines. But the bulkier, slower crows fall prey to the more agile falcons.
– Peregrine vs. red-tailed hawk – Red-tails are bulkier raptors with a wingspan exceeding 4 feet. They outweigh the smaller peregrine by several pounds.
– Peregrine vs. bald eagle – America’s national symbol dwarfs the peregrine, typically weighing 10-15 pounds with a wingspan over 6 feet.
So while peregrines are considered medium-sized falcons, they are relatively compact compared to many of the birds they prey on. Their small size belies the power and speed of these remarkable hunters.
Sexual Size Dimorphism
There is considerable sexual dimorphism between male and female peregrines. As mentioned, females typically measure 19-24 inches in length and weigh around 1.5 pounds. They need the extra bulk to produce and incubate eggs.
Males are 15-20 inches long on average and weigh about 1 pound. The smaller size benefits the males’ aerial agility and speed since they do most of the hunting.
Because of this size differential, the two sexes employ slightly different hunting strategies. The larger females tend to take heavier prey and can retrieve it in flight, while the more agile males often target smaller birds and bats by making high velocity dives upon them.
Falcon chicks and juveniles
Newly hatched peregrine chicks weigh approximately 1.5 to 2 ounces. They remain covered in white down for about 2 weeks as they grow rapidly.
At 3 to 4 weeks old, the juvenile plumage starts growing in. At this fledgling stage, young peregrines are about 70% of adult size. They’ll reach full adult dimensions after 8 weeks or so.
Range of Sizes
The average sizes listed for peregrine falcons encompass birds across their worldwide range. But there are some geographical variations:
– Largest peregrines – The largest subspecies is the Peale’s peregrine of the Pacific Northwest, which can weigh up to 2.2 pounds.
– Smallest peregrines – The small F.p. minor of Australia and Indonesia weighs only about half a pound.
– Arctic peregrines – Birds breeding in Arctic regions are typically bigger with more feather insulation.
– Tropical peregrines – Those in tropical areas are leaner and smaller to aid heat dissipation.
So peregrine dimensions can vary somewhat depending on subspecies and where they live. But most fall within the typical size ranges described in this article. The peregrine is a morphologically diverse species adapted to many habitats and locations.
Role of Size in Hunting
The peregrine falcon’s medium size, muscular build, and flight capabilities provide it with several key advantages as a predator:
Speed and maneuverability
Weighing around 1 to 1.5 pounds, the peregrine has an optimal weight-to-wing ratio that enables incredible agility and velocities. If they were any bulkier, they would lose this aerial edge.
Strength and impact forces
Although not the largest birds, peregrines pack impressive power in their compact frames. They can achieve devastating impact forces of well over 1,000 psi when striking prey in a steep dive. Their feet deliver massive grip strength to hold prey.
Stealth and precision
With their aerodynamic profiles, peregrines can slice through the air at high speeds while minimizing drag. This allows them to maintain the element of surprise when ambushing prey from above. Controlled precision during dives enables targeting vulnerable areas.
Defense against injury
The peregrine’s compact musculoskeletal system and dense feathers provide protection when crashing into prey at speeds exceeding 200 mph. Their size helps them withstand the immense forces involved.
Overall, the typical physical dimensions of the peregrine provide an optimal balance of speed, agility, power, and toughness befitting an avian hunting specialist.
Conclusion
In summary, a full grown peregrine falcon averages:
– 1 to 1.5 pounds in weight
– 15 to 24 inches long from head to tail
– 39 to 43 inch wingspan
The female peregrines are noticeably larger than the males. But both sexes display an impressive combination of swiftness, maneuverability, and kinetic impact forces thanks to their compact size and muscular physiques. The peregrine’s medium dimensions belie its deadly skillset as one of nature’s premier aerial hunters.
