An apparent hybrid Red x Black Kite in Spain

Shortly after publishing the post on Siberian Black Kites in Europe, I received a picture of what I suspected was a Siberian Black Kite from Central Spain. To my surprise, when the whole set of photographs arrived, it showed what looked like an adult hybrid Red x Black Kite. The pictures showed a robust and large bird (similarly sized to the Red Kites nearby), with a rufous plumage similar to that of Red Kite (note that the birds look unusually bright due to the strong reflection from the snow underneath), but other features such as wing-formula and tail shape point towards a Black Kite ancestry. Since there are few published photographs of this kind of hybrid, the photographer Javier Parrilla kindly agreed to post his fabulous pictures here.

Presumed hybrid Red x Black Kite, adult, January 2020, Madrid, Spain (Javier Parrilla).

To my eyes, the main features supporting the Black Kite influence include:

• Wing formula, including 6 fingers (not 5, as in Red Kite).

• Relatively squared and brownish tail with a regular and thick barring.

• Brownish iris, perhaps suggesting a young adult, supported too by a hint of ear-patch.

• Lack of darkish greater coverts and carpal in the underwing.

• The white wing patch typical of Red Kite is darkened by a greyish barring typical of Black Kite. The inner part of the primaries does look pale (definitely paler than in Black Kite) but not purely white as in Red Kite.

However, the Red Kite ancestry is likewise obvious in a number of features:

• Size and structure, including long neck and powerful wings.

• Overall plumage coloration, including contrasting dark shafts on most of the body and underwing coverts.

• Bill size and shape, giving a typical Red Kite ‘facial expression’.

• Upperwing coverts with rufous fringes contrasting with the dark feather centre.

Hybridisation between Red and Black Kites has been reported on numerous occasions, mainly in Scandinavia and Baltic countries but also in Germany and the UK, with a few cases also claimed from the wintering grounds in Southern Europe. Three cases of presumed hybrids from Estonia were published here by Paal & Forsman. Interestingly, most of the birds identified as hybrids in the field look much more similar to Red Kite (eg here or here) than the bird shown in this post, raising the question of whether those birds (or this one) were actually backcrosses rather than F1 hybrids.

The combination of European Black Kite and Red Kite traits make these hybrids look confusingly similar to West Siberian Black Kites, especially due to the eye-catching white on the wings. However, in Siberian Birds the white is usually limited to the base of the outer primaries, looking like a contrasted small patch. In the hybrids the white is seemingly less contrasted and more extended over the whole set of primaries. I guess that size, structure and plumage details should be enough to correctly clinch the id if seen well enough, but distant birds or poor shots could definitely complicate the identification (see for instance the bird 2 in the above note by Paal & Forsman).

I’d like to thank Javier Parrilla for sharing the pictures with me and allowing their publication here.

Presumed hybrid Red x Black Kite, adult, January 2020, Madrid, Spain (Javier Parrilla). Intermediate in shape between Red and Black Kites, although apparently as large as the former in direct comparison.

Presumed hybrid Red x Black Kite, adult, January 2020, Madrid, Spain (Javier Parrilla). In this picture the pattern of the upperwing coverts and the Red Kite ‘facial expression’ are obvious, but the tail strongly points towards Black Kite.

Presumed hybrid Red x Black Kite, adult, January 2020, Madrid, Spain (Javier Parrilla).

Presumed hybrid Red x Black Kite, adult, January 2020, Madrid, Spain (Javier Parrilla). The Black Kite influence is obvious, including the wing formula with 6 fingers and shallow tail fork, with marked tail barring. Still, the bird looks structurally closer to Red Kite.