Milvus milvus
red kite

Milvus milvus is endemic to the western Palearctic region in Europe and northwest Africa. Formerly, these birds of prey also occurred in northern Iran. They are rare kites that are resident in western Europe and northwest Africa. Red kites from northeastern and central Europe migrate further south and west, reaching south to Turkey for the winter season. Vagrant birds have been recorded as far north as Finland and south in Israel and Libya. (Newton, et al., 1996; Snow and Perrins, 1998)

Red kites are a wide-ranging species with a wide habitat tolerance. Their only requirements are large, mature trees in which to build nests. Generally these nests are built 10 to 15 m above ground. Sometimes red kites take over an old crow or buzzard nest. Red kites can be very protective of their nesting area, but are not highly territorial of their entire breeding territory. Most red kites nest within 20 km of where they were reared. (Mougeot, 2000; Newton, et al., 1996)

Red kites are brownish-chestnut in color with a mix of orange/buff and darker brown or black streaking. The main wing feathers (secondaries and primaries) are dark brown, which contrast with white patches under the wings. They have pale grey heads which are streaked with black. The bright yellow legs and feet can often be seen in flight. They have hooked beaks which are very sharp and designed for tearing meat. Females are generally larger ranging from 1000 to 1300 g in weight, males are 800 to 1200 g. Their wingspan ranges from 175 to 195 cm and body length from 60 to 66 cm. (Snow and Perrins, 1998)

Red kites are monogamous and pair-bond for life, usually staying with each other year-round. Courtship each year renews the bond the pair already have. Mated pairs are more successful in reproduction with experience.

Courtship begins for established pairs in March. The birds play courtship games, such as flying towards each other and then turning and twisting away from each other at the last moment. They also have mock talon grappling fights, spinning in mid air, spiraling toward the ground, parting at tree level. Occasionally pairs courting this way fail to release each other in time and die. (Mougeot, 2000)

Red kites reach maturity between 2 and 4 years of age. These birds normally pair for life, although, in winter they may spend time apart or in communal roosts. Winter is the best time for viewing kites because it minimizes disturbance to breeding kites. They are notorious for being easily disturbed at the nest.

One to three eggs are normally laid in April, produced at 3 day intervals. This ensures that there will be a dominant chick who will likely outlive his siblings. Incubation time is 31 to 32 days with an extra 3 days per additional egg.

Fledging can take 7 to 9 weeks, depending on food availability. At around 6 weeks the chicks will move away from the nest to exercise their wings. Even after their first flight, young do not move far from their nests as parents continue to feed them around the nest for several weeks. Young attain adult plumage at around 1 year and will breed at about 3 years. (Mougeot, 2000; Newton, et al., 1996)

Both parents assist in nest-building, usually in hardwood trees. Red kites are protective of the nest area, but not of the entire breeding territory. The female carries out the majority of incubation with relief from the male for several 20-minute breaks during the day for feeding and exercise. The parents stay alert for nest predators, such as crows and ravens. When the chicks hatch, the male bird brings food to the nest for the female to tear into small pieces to feed them. Parents will continue to feed the young a few weeks past the fledgling stage. (Mougeot, 2000; Newton, et al., 1996)

Captive red kites are known to have lived 26 years in captivity. Wild records are unavailable, but related Milvus migrans have been recorded living up to 24 years in the wild. (Richards, 1998)

Red kites nest in trees, often close to other kites. In the winter, many kites roost together. Red kites are social in winter and mate for life, so occur in pairs during the breeding season. Some red kite populations are migratory; others that occur in milder regions are sedentary. Those that do migrate remain on the same continent, and often return to their natal grounds to breed. (Carter and Grice, 2000; Mougeot, 2000)

Red kite home-ranges generally consists of their nesting and hunting area. Average home range size is poorly defined and highly variable, as kites may hunt 2 to 25 km from their nest. (Richards, 1998)

Red kites, like other carrion birds, feed on widely dispersed food sources, so they may communicate at roost sites. Individuals tend to find food for themselves or by following another. (Richards, 1998)

Red kites are primarily scavengers, but they are also predators, especially during the breeding season when they must feed their young. They eat a wide variety of live prey, primarily small mammals such as rabbits, voles, and field mice, but also including birds, worms, and invertebrate prey. Red kites glide lower than their usual soaring height to hunt live prey, visually searching for movements on the ground. They then dive quickly and grab prey in their talons. (Snow and Perrins, 1998)

Goshawks (Accipiter gentilis) are the only known natural predators of adult red kites. The main threat is from human activity. Red kites have been targeted by egg thieves and illegal use of poisoned baits in carcasses, even though they are not set specifically for red kites. Nestlings and eggs are also vulnerable to nest predators, although both parents actively defend the nest. At signs of predators females signal to her fledglings who "play dead," even to the extent that a fox will believe them to be dead and leave, thinking it can return to eat them later. (Richards, 1998; Snow and Perrins, 1998)

Red kites are important predators and scavengers in the ecosystems they inhabit. Parasites found on these birds include: an acanthocephalan (Centrorhynchus milvus) and a trematode (Phagicola ascolonga). (Kuntz and Chandler, 1956; Schmidt, 1975)

Red kites prey on rabbits and other rodents that act as agricultural pests. They also help by removing dead carcasses that could spread disease. (Richards, 1998)

There are no known adverse effects of Milvus milvus on humans.

Red kites are directly persecuted by poachers, forestry workers, tourists, and others. Habitat destruction, shortage of food, over-use of pesticides and other chemicals, over-exploitation, collisions, and petroleum and oil pollution are all indirect threats to Milvus milvus. They are considered near-threatened by the IUCN. Populations are in decline in areas that were previously considered strongholds of this species, including Germany, Spain, and France. (Richards, 1998)

The closest relative of red kites are black kites (Milvus migrans). Red and black kites co-occur in countries like Spain and occasionally hybridize.