Basic Principles
Europe has two species of Milvus kites: Red Kite and Black Kite. In Britain the former is an increasing resident, while Black is a rare visitor, mostly seen in spring and autumn. In a wider context, Red Kite is a western, typically European species, while Black has a huge range extending across the entire Palaearctic region from the Atlantic to the Pacific Ocean.
Although the two are quite different, misidentifications do occur. Plumage-wise Red Kite is the less variable of the two, as there is little individual or geographical variation. In Black Kite, however, both individual and geographical variation are extensive. Getting to grips with this variation is one of the keys to safely separating the two species.
Geographical variation
Red Kite looks the same across its entire range from Scandinavia to the Mediterranean. Once you familiarise yourself with the juvenile and adult plumages of the species, that knowledge will apply to all birds anywhere in Europe.
However, several Black Kite forms are found within the boundaries of the Western Palaearctic. European birds are the nominate migrans, also called Western Black
Kite, whereas Far Eastern birds from China and Japan are lineatus, known as Black-eared Kite, which is regarded by some as a full species.
Between Black and Black-eared Kites is a wide transition zone, from Russia to Mongolia and western China, where these two forms interbreed, resulting in a recognisable hybrid form: Eastern Black Kite. In addition to these forms the Indian subcontinent has its own resident Black Kite subspecies, govinda, and in Australia and Indonesia the local subspecies is affinis.
The two African forms aegyptius and parasitus were until recently regarded as subspecies of Black Kite, but are now widely recognised as constituting a separate species, Yellow-billed Kite.
Migration patterns
Red Kite is largely resident over much of its range, but Scandinavian birds, immatures in particular, do leave their breeding grounds and move to southern Europe for the winter. Black Kites, on the contrary, are strongly migratory.
European birds start to leave from July-August, when thousands are counted in southern Spain crossing to Africa. These birds winter in West Africa, with high numbers recorded in the Sahel, along the southern fringes of the Saharan desert.
More easterly populations take the eastern fly-way through the Middle East, ending up in sub-Saharan East Africa. More recently, numbers of birds wintering in the Near East, for instance in Israel, have rocketed.
As a rule of thumb most Black Kites have left Europe by the end of September, while the hybrid Eastern Black Kite, common in the Levant and the Middle East, is
a later migrant and wintering numbers start to build up during late September and October. This is also when these rather diagnostic-looking birds can be seen further west in Europe, often causing heated discussions about the possibility of Black-eared Kite.
The Far Eastern subspecies lineatus has not yet been recorded in Europe, and all the look-alikes seen well enough have been Eastern Black Kites. Even most of the wintering birds as far east as Arabia and India show a mix of characters from migrans and lineatus and are thus best referred to as Eastern Black Kites. Very few individuals tick all the boxes to be regarded as pure Black-eared Kites.
Body proportions
These are medium-sized raptors, differing from the well-known buzzard shape by their long wings and tails. Compared to a buzzard, flight is elegant and the movements slow and gentle, owing to the long wings and relatively low wing loading (the bird’s weight in relation to its wing surface area).
Red Kite has long, narrow and flexible wings and a very long and deeply forked tail; its active flight is one of the most graceful of all our raptors. Black Kite has slightly broader wings comparatively and the tail is shorter, which makes the flight appear less elegant.
Both species have very short legs both for their body size and compared with most other raptors, which gives them a very special jizz when perched. The feet seem to be attached quite high up on the body, with a major part of the bird trailing behind and ‘hanging’ below the perch.
At rest, Red and Black Kites can often be told from one another by the silhouette. The very long tail of the former protrudes well beyond the wing-tips, while in Black Kite the tail and wing-tips fall more equally. However, it is worth remembering that first-year Red Kites are shorter tailed than adults.
Distant birds
When identifying distant kites, where plumage characters cannot be evaluated, the different silhouettes of the two species are important. Red Kite has very long, narrow wings which, when soaring, are pressed well forward. The outer wing, the ‘hand’, appears to be narrower than the arm, the ‘fingers’ are long and the tip is narrow and rounded. The tail is very long, with a narrow base and pointed corners. All this creates a silhouette which is one of the most elegant of all European raptors.
By comparison Black Kite’s wings are slightly broader, more rectangular and the wing-tip is more square cut. The tail is also shorter and less clearly forked, often with no visible fork at all.
Juvenile Red Kites have a less extreme shape compared to adults and could be a potential pitfall. The wings are somewhat shorter – therefore appearing broader – and the tail is shorter with a shallower fork. Although more compact than the adult, first-year Red Kite still appears longer winged and longer tailed than any Black Kite.
Close up
When birds are seen close enough to discern plumage tones, identification should be straightforward. Red
Kite is a colourful and contrasting mix of bright rufous, cinnamon, black and white, while Black Kite appears uniform and dull by comparison.
Red Kite’s underwing window on the primaries is bright white, and only thinly and indistinctly barred; it reaches the trailing edge of the wing and is sharply set against the dark secondaries. In Black Kite the window is poorly defined, typically just a shade lighter grey than the rest of the underwing, and is coarsely yet diffusely barred.
Eastern Black and Black-eared Kites can be a bit more challenging, as they often show some clear white markings in the underwing primaries, but the primary window is always coarsely barred and irregularly shaped, never all white to the edges as in Red Kite.
Adult Yellow-billed Kite is often even more uniform on the underwing than Black Kite, but is often recognised by being clearly rufous overall. At close range the all-yellow bill of the adults is a giveaway, but dark-billed juveniles can be extremely similar to juvenile Black Kite, which may share the same range in winter. Although the juveniles may be almost identical in plumage, the breeding seasons of Yellow-billed and Black differ, leading to differences in the timing of moult and plumage wear, which can be a useful clue when identifying Milvus kites in Africa.
Wing formula
Red Kite is quite unique in showing only five long, fingered primaries, with the sixth (counting inwards) being short and falling more or less in line with the trailing edge of the hand. Black Kite is more variable, as the wing formula differs between subspecies.
Black Kite has five well-fingered primaries, with the sixth being clearly shorter, often protruding as a separate but shorter finger. This makes the outer wing look both broader and blunter compared to Red Kite. Black-eared Kite has the broadest wing-tip of all, with six deeply fingered primaries in the wing-tip, with the innermost sixth finger long and pointed and well protruding. Eastern Black Kite is intermediate, often showing a wellformed and protruding sixth finger, longer and more prominent compared to the average Black Kite. The Yellow-billed Kites of Africa only have five deeply splayed fingers, while the sixth is the shortest compared to any form of Black Kite.