2008/9 Schools Wikipedia Selection. Related subjects: Birds
The Red Kite (Milvus milvus) is a medium-large bird of prey in the family Accipitridae, which also includes many other diurnal raptors such as eagles, buzzards and harriers. The species is currently endemic to the Western Palearctic region in Europe and northwest Africa, though formerly also occurred just outside in northern Iran. It is a rare species which is resident in the milder parts of its range in western Europe and northwest Africa, but birds from northeastern and central Europe winter further south and west, reaching south to Turkey. Vagrants have reached north to Finland and south to Israel and Libya.
Physical characteristics and behaviour
The Red Kite is 60–66 cm long with a 175–195 cm wingspan; males have a weight of 800–1200 g, and females 1000–1300 g. It is an elegant bird, soaring with long wings held at a dihedral, and long forked tail twisting as it changes direction. The body, upper tail and wing coverts are rufous. The white primary flight feathers contrast with the black wing tips and dark secondaries. Apart from the weight difference, the sexes are similar, but juveniles have a buff breast and belly. The call is a thin piping, similar to but less mewling than Common Buzzard.
The species nests in trees, often close to other kites; in winter, many kites will roost together. In the spring the nests are obvious at the tops of trees. From a distance they look like rookeries, including the swirling pattern of the birds. From closer to, one can see that the birds are not rooks but kites because of the more slender wings.
At signs of danger a mother will signal the young who will "play dead" to the extent that a fox will believe them to be dead and leave them, thinking it can return to eat them later.
Differences between adults and juveniles
Adults differ from juveniles in a number of characteristics:
- Adults are overall more deeply rufous, compared with the more washed out colour of juveniles;
- Adults have black breast-streaks whereas on juveniles these are pale;
- Juveniles have a less deeply-forked tail, with a dark subterminal band;
- Juveniles have pale tips to all of the greater-coverts (secondary and primary) on both the upper- and under-wings, forming a long narrow pale line; adults have pale fringes to upperwing secondary-coverts only.
These differences hold throughout most of the first year of a bird's life.
Distribution and status
The Red Kite inhabits broadleaf woodlands, valleys and wetland edges, to 800 m. It is endemic to the western Palearctic, with the European population of 19,000-25,000 pairs encompassing 95% of its global breeding range. It breeds from Spain and Portugal east through central Europe to Ukraine, north to southern Sweden, Latvia and the UK, and south to southern Italy. There is also a population in northern Morocco. Northern birds move south in winter, mostly staying in the west of the breeding range, but also to eastern Turkey, northern Tunisia and Algeria. The three largest populations (in Germany, France and Spain, which together hold more than 75% of the global population) all declined during 1990-2000, and overall the species declined by almost 20% over the ten years. The main threats to this species are poisoning, through illegal direct poisoning and indirect poisoning due to pesticides, particularly in the wintering ranges in France and Spain, and changes in agricultural practices causing a reduction in food resources. Other threats include electrocution, hunting and trapping, deforestation, egg-collection (on a local scale) and possibly competition with the generally more successful Black Kite M. migrans.
German populations declined by 25-30% between 1991 and 1997, but have remained stable since then, with the populations of the northern foothills of the Harz Mountains (the most densely populated part of its range) suffering an estimated 50% decline from 1991-20015. In Spain the species showed an overall decline in breeding population of up to 43% for the period 1994 to 2001-02, and surveys of wintering birds in 2003-04 suggest a similarly large decline in core wintering areas. The Balearic Islands population has declined from 41-47 breeding pairs in 1993 to just 10 in 2003. In France, breeding populations have decreased in the northeast, but seem to be stable in southwest and central France and Corsica. However, populations elsewhere are stable or undergoing increases. In Sweden the species has increased from 30-50 pairs in the 1970s to 1,200 breeding pairs in 2003. In Switzerland, populations increased during the 1990s, and have now stabilised.. However, according to a report by the Welsh Kite Trust, the UK is the only country in which the Red Kite population is increasing. Red Kites are decreasing in their three strongholds of Spain, France and Germany, and population increases have stagnated in Sweden and Switzerland.
In the United Kingdom, the breeding population eventually became restricted to a handful of pairs in Wales, but recently the Welsh population has been supplemented by re-introductions in England and Scotland. In 2004, from 375 occupied territories identified at least 216 pairs were thought to have hatched eggs and 200 pairs reared at least 286 young. In 1989 six Swedish birds were released at a site in north Scotland and four Swedish and one Welsh bird in Buckinghamshire. Altogether, 93 birds of Swedish and Spanish origin were released at each of the sites. In the second stage of reintroduction in 1995 and 1996, further birds were brought over from Germany to populate the areas of Dumfries and Galloway, and the Derwent Valley.
The reintroductions in The Chilterns have been a particular success, with a now well-established strong population across Oxfordshire, Berkshire and Buckinghamshire. The Kites are a common sight above the houses of the Buckinghamshire villages of Stokenchurch and Haddenham and also the towns of Princes Risborough and as far east as Chesham, the Oxfordshire town of Wallingford and their surrounding areas. Sightings are common along the M40 between Oxford and Wycombe, all the way down to Reading and Newbury on the M4. In June 2006, the UK-based Northern Kites Project reported that kites have bred in the Derwent Valley in and around Rowlands Gill, Tyne and Wear for the first time since the re-introduction.
Red Kites were extinct in Ireland by the middle nineteenth century, due to persecution, poisoning and woodland clearance. Some Scottish pairs did visit Ireland in the summers, but it was proposed by statisticians that only one pair had nested permanently. In May 2007, Minister for the Environment Heritage and Local Government Dick Roche announced an agreement to bring at least 100 birds from Wales to restock the population as part of a 5-year programme in the Wicklow Mountains, similar to the earlier Golden Eagle On the 19th July 2007 the first thirty red kites were released in Co. Wicklow. project.
Populations and trends by country
The following figures (mostly estimates) have been collated from various sources. They cover most of the countries in which Red Kites are believed to have bred.
|Norway||1980||0||0||Bred occasionally in 19th century|
|Sweden||2000s||1000||+||Increase from 400 pairs in 1993|
|Denmark||2004||24||+||Extinct c.1920, then recolonised (from Sweden) 1970s|
|Scotland||2006||104||+||Extinct 1886, reintroduced 1989–1992|
|Northern Ireland||2007||0||0||Reintroduction due to start in 2008|
|Wales||2006||400–500||+||Declined to 2 pairs in 1930s, then recovery|
|England||2006||388+||+||Extinct 1870s, reintroduced 1989–1992|
|France||ca.1995||2250–4200||0/–||2300–2900 pairs 1980s|
|Netherlands||ca.1998||<5||+||Extinct 1852, recolonised 1976|
|Belgium||ca.1995||50–60||+||Declined to 1–3 pairs early 1970s, then recovery|
|Germany||1999||9000–12000||–||15000–25000 pairs 1980s|
|Poland||ca.1998||650–700||+||400–450 pairs 1980s|
|Latvia||1992||0–50||+||Extinct 1964, then recolonised|
|Lithuania||1988||1–2||+||Extinct, then recolonised 1981|
|Belarus||1997||1||+/–||Extinct 1950s, recolonised 1985; 10 pairs 1990|
|Czech Republic||1993–94||30–50||+||Extinct late 19th century, recolonised 1975|
|Switzerland||ca.1995||800–1000||+||Declined 19th century, later recovery; 235–300 pairs late 1980s|
|Austria||2000||0–2||–||Extinct 1950, recolonised 1970s; 10 pairs 1990|
|Hungary||ca.1998||1+||–||30 pairs 1950s|
|Bulgaria||0||?||May breed but no proof|
|Croatia||0||?||2–5 pairs 1980s|
|Bosnia and Herzegovina||0||?|
|Republic of Macedonia||0||?|
|Italy||ca.2002||300–400||0/+||70–150 pairs late 1980s|
|Turkey||0||?||May have bred in past but no proof|
|Algeria||0||?||Bred in 19th century, now extinct|
|Tunisia||0||?||Bred in 19th century, now extinct|
|Spain||1994||3328–4044||–||10000 pairs 1977|
|Morocco||ca.1992||10–100||–||In danger of extinction|
|Canary Islands||0||0||Extinct 1970s|
|Cape Verde||2000||1?||–||50–75 pairs late 1980s; effectively extinct|
This species was first described by Linnaeus in his Systema naturae in 1758 as Falco milvus.
The Red Kite has been known to successfully hybridize with the Black Kite in captivity where both species were kept together, and in the wild on the Cape Verde Islands.
The Red Kites on the Cape Verde Islands are (or rather were) quite distinct in morphology, being somewhat intermediate with Black Kites. The question whether the Cape Verde Kite should be considered a distinct species (Milvus fasciicauda) or a Red Kite subspecies was never really settled. A recent mtDNA study on museum specimens suggests that Cape Verde birds did not form a monophyletic lineage among or next to Red Kites.
However, this interpretation is problematic: mtDNA analysis is very susceptible to hybridization events, the evolutionary history of the Cape Verde population is not known, and the genetic relationship of Red Kites in general is very confusing, with geographical proximity being no indicator of genetic relatedness and the overall genetic similarity high, perhaps indicating a relict species.
Given the morphological distinctness of the Cape Verde birds and the fact that the Cape Verde population was isolated from other populations of Red Kites, it cannot be conclusively resolved at this time whether the Cape Verde population was not a distinct subspecies (as M. migrans fasciicauda) or even species that frequently absorbed stragglers from the migrating European populations into its gene pool. More research seems warranted, but at any rate the Cape Verde population is effectively extinct since 2000, all surviving birds being hybrids with Black Kites (which merely raises further questions about their taxonomic status).
One of the best places to see the Red Kite is Scania in southern Sweden. It may be observed in one of its breeding locations such as the Kullaberg Nature Preserve near Molle. One of the best places to see them in the UK is Gigrin Farm near Rhayader, mid Wales, where hundreds are fed by the local farmer as a tourist attraction.
More recently in the UK the Oxfordshire part of the Chilterns has many Red Kites. The best place to see them is on the Ridgeway, but they are advancing north-westwards over the flatter centre of Oxfordshire and have been seen in Cowley (East Oxford).