Rupert (2009) – male hybrid falcon – peregrine (Falco peregrinus) X gyrfalcon (Falco rusticolus) X saker (Falco cherrug)
A hybrid is a cross between different species. In captivity many species of falcon are hybridised to gain the characteristics of both species. A hybrid also exhibits 'hybrid vigour' which hopefully makes for a better hunting bird. Hybrids do occur in the wild but as they are not as perfect as pure species they usually do not survive and replicate themselves in the wild.
The peregrine is renowned for its speed, reaching over 320 km/h (200 mph) during its characteristic hunting stoop (high-speed dive), making it the fastest bird in the world, as well as the fastest member of the animal kingdom. According to a National Geographic TV program, the highest measured speed of a peregrine falcon is 389 km/h (242 mph)
The gyrfalcon is the largest of the falcon species. The abbreviation gyr is also used It breeds on Arctic coasts and tundra, and the islands of northern North America and the Eurosiberian region. It is mainly a resident there also, but some gyrfalcons disperse more widely after the breeding season, or in winter. Individual vagrancy can take birds for long distances. Its plumage varies with location, with birds being coloured from all-white to dark brown. These colour variations are called morphs. Like other falcons, it shows sexual dimorphism, with the female much larger than the male. For centuries, the gyrfalcon has been valued as a hunting bird. Typical prey includes the ptarmigan and waterfowl, which it may take in flight; it also takes fish and mammals.
The saker falcon is a large hierofalcon, larger than the lanner falcon and almost as large as gyrfalcon at 45–57 cm (18–22 in) length with a wingspan of 97–126 cm (38–50 in). Males weigh between 730–990 g (26–35 oz) and females 970–1,300 g (34–46 oz). It resembles a larger but browner gyrfalcon. It is larger and more heavily built than the related lanner falcon.
Saker falcons tend to have variable plumage. Males and females are similar, except in size, as are young birds, although these tend to be darker and more heavily streaked. The call is a sharp kiy-ee or a repeated kyak-kyak-kyak.