Dear All,
This week I reported a bird seen on 8th Jan in Nairobi National Park,
that I thought was a good candidate for Black-eared Kite Mivus
(migrans) lineatus, which had not been recorded in Africa before.

I wrote to Dick Forsman with the images, and had a reply almost by
return. It has raised some really interesting points, and certainly
gives encouragement to people for giving Black Kites a little more
attention, and by reporting birds resembling the NNP bird it could
lead to interesting data relative to a very extraordinary situation
regarding intraspecific population dynamics currently taking place,
but read the following relevant pieces of correspondence….

“Dear Dick,
…..I wonder if you could help me with the attached Kite that I
photographed in Nairobi National Park last weekend.
I had never considered lineatus as a potential for reaching us, so had
never boned up on the criteria for separating it from migrans. Last
Sunday there was a group of kites wheeling around over a clearing in
the forest, so for much of the time they were behind the trees. With
the naked eye one bird looked dark on the underwings with very
prominent white commas at the base of the outer primaries, the likes
of which I had never seen before in Africa. I tried to get images but
the trees proved a problem, I did manage two that are attached, but
the final circuit and it was gone. As I had no preconceived ideas as
to what to look for in a lineatus, when I downloaded the images I
thought it worth checking lineatus and see what was on Google Images.
I was pleasantly shocked to find that the extensive white bases to the
outer primaries was indeed a good character, but then on going through
the other feature such as heavy streaked upper breast contrasting with
unmarked lower breast to undertail coverts, I thought it worth
mentioning. It certainly looks like a good candidate for Black-eared
Kite, but I think that if it is it would be the first in sub-saharan
Africa.
Can you please give me your thoughts on this bird,
Very best for now
Brian

Hi Brian,
….I do not know if you have seen my new book "Flight Identification of
Raptors...." (see bottom of this mail), but it covers this problem in
greater detail than any literature up to now. If you can't get hold of
it, I can try
to wire you the relevant text. Birds looking like lineatus are not
necessarily that. For instance, most of the birds reaching the
Mid-East in winter, superficially looking like lineatus, are
intergrades between migrans
and lineatus and I have seen and photographed these birds on every of
my trips to Ethiopia. They appear to be regular in E Africa and one
was documented some years ago as far south as Namibia. I think they
have been overlooked in the past, as very few people have paid any
attention at all to "Black Kites". Now that Yellow-billed and Black
have been split, there has been some more interest for these birds.
Some of these intergrades, which are easily separated from nominate
Black by the white primary patch, can be very similar to lineatus and
you really need to see them close to get the important details, such
as colour of bare parts. I have called them "Eastern Black Kite" in
the book, and they occur across a vast area from the Ural Mts in the
west to at least C Mongolia in the east. For instance, practically all
winter records of BK in Europe are of such birds, as nominate BK is a
long distance migrant wintering in Sub-Saharan
Africa. The number of wintering BK in the Mid-East has gone up nearly
100x in the last 30 years, and this can be attributed to these birds
alone. Whether their population has exploded or whether they've
changed
their wintering areas I don't know. With this in mind, they may have
become more common in Africa also during this time.
Your bird definitely looks like Eastern, although from these images it
is not possible to exclude a "real" lineatus, which, of course, would
be much more unlikely.
All the best for you too,
Dick”

So Kites have become interesting, and there is a reason to filter
through them to see if indeed Eastern Black Kites are spreading into
and down into the African continent. Everyone can help here if they
know what to look for.

The NNP bird is the first to be recorded in East Africa, but as Dick
says that with a general disinterest in Black/Yellow-billed Kites, it
is probably being overlooked so it is time to find out if this is the
case and we are overlooking this interesting change in the winter
distribution for this form.

For those that want to obtain what is currently the last word on
flying raptor identification for Europe, North Africa and the
Middle-East, here is the location….

"Flight Identification of Raptors of Europe, North Africa and the
Middle East", 2016, Bloomsbury Publications  Forsman, Dick

This title is available also as a handy electronic ePub version for
smartphones and tablets.

Best to All
Brian