The gyrfalcon is the largest falcon in the world, and it is somewhat larger than a peregrine falcon. Gyrfalcons live in the far north, in the Arctic, where they are top predators.
Animal Diversity Web gives an average total length of 53 centimeters for male gyrfalcons and 56 centimeters for females. A male gyrfalcon weighs about 800 to 1,350 grams, and Alaska Department of Fish and Game gives females as weighing about 1,200 to 2,100 grams. A female is bigger than a male.
A gyrfalcon hunts by scanning from a high rock perch or while flying, and it uses keen eyesight to spot potential prey. It often hunts by flying fast and low over the ground, usually in a level chase rather than a steep dive, and it may chase its prey over long distances.
Gyrfalcons eat mostly other birds, and ptarmigan are the gyrfalcon's main food. A gyrfalcon also eats waterfowl and seabirds, and some small mammals, such as ground squirrels and hares.
Falconry is one of the oldest sports, dating back some 4,000 years. In the Middle Ages, only a king could hunt with a gyrfalcon. The male gyrfalcon is called a gyrkin in falconry.
Male gyrfalcons begin defending a nesting territory in mid-winter. Gyrfalcons often return to the same nest site year after year. A gyrfalcon does not build its own nest, and it nests on cliffs. Some use an old nest that another bird, such as a raven, built.
Gyrfalcons that nest in the Arctic often start laying eggs while the temperature is still below freezing. A gyrfalcon usually lays three or four eggs, and the eggs take about five weeks to hatch.
For the first one to three weeks, the male does all or most of the hunting while the female broods the young. At gyrfalcon nests in west Greenland, food deliveries peaked in the morning and evening. Adult gyrfalcons bring food to the nest for their young.
Young gyrfalcons begin short practice flights at about five weeks old and spend the next eight weeks or more honing their flying. At 3 to 4 months old, young gyrfalcons become independent of their parents. Gyrfalcons typically become sexually mature at three to six years old.
Words to know
- ptarmigan: a bird
- falconry: hunting with falcons
- gyrkin: a male gyrfalcon
- broods: keeps eggs warm
