Black Kites (Milvus migrans) are starting to show up entering from The Strait of Gibraltar after spending the winter in Africa. Hence it is a good moment to refresh the basics about Kite´s ID to differ between the Black and the Red Kite (Milvus milvus), both in flight and perched.
Although aparently they are species quite strait forward to identify, sometimes (especially in poor light conditions), very distant observations and some excepcional individuals, can be somewhat more complicated. Therefore a closer look could be necessary.
As a rule, the Red Kite is a bird with a much more marked contrast plumage than the Black Kite. This feature can be especially notorious in medium coverts, having the Black Kite a more uniform plumage unlike the Red Kite with a more pronounced pattern appearance. Perched individuals and in low light or backlit (and therefore plumage characteristics are not well seen), it is helpful to look at the tail projection. We will identify Red Kites easily when the tail-tip protrudes from folded wing-tips. If the tail-tip is more or less at the same level as the primaries tips, we will be observing a black Kite instead.
In flight, the Red Kite has a long and deeply forked tail, usually paler than the upper parts. The underwing shows a white patch contrasting with the darker secondaries and wing tips (“fingers”). The Black Kite seem to have a broader wing and occasionally 6 “fingers” can be observed in wing-tips in contrast to 5 usually seen in Red Kites.
In Black Kite there is a rufous variation (althought more common in the Middle East) that can easily be mistaken for Red Kites due to present a rufous underbody and paler head!