It was surprisingly quiet today at Tuti when I visited with Stephen. I was expecting a lot of migrant land birds, but there were virtually none. There were still quite a few terns moving up the White Nile, plus some Lesser Black-backed Gulls and a Black-headed Gull. The best sighting was a couple of probable Little Terns. The Atlas of Sudan's Birds by Nikolaus dates from 1987, when Saunder's Tern was still considered a subspecies of Little Tern. He mainly shows sightings on the Red Sea coast and shows inland records from Khartoum and just south of the Egyptian border. He comments that the nominate race (i.e. what is now known as Little Tern) has not been recorded.
Unfortunately, we saw the birds late and just as they were passing us. I managed to shoot a few quick photos, but was relying on autofocus to pick them up. What can be seen from these shots is that the white forehead extends quite far back over the eye (hence my need to include the fourth shot that is badly out of focus), while it extends less far back in Saunder's Terns. The outer two primaries of Saunder's Tern should be black at this time of year, and these birds did not show this. There are also subtle differences in rump coloration between the two, but it would be hard to spot from these pictures. Saunder's Tern is mostly coastal, while Little Tern is known to head inland and along rivers. It is therefore reasonable to assume that the birds on the Red Sea coast are Saunder's Terns (though there could also be some Little Terns) and that the inland records are of Little Terns. I doubt that my poor photos are good enough to confirm this, unless I can find an expert that is able to verify them. It would be nice to confirm the presence of Little Tern in Sudan.
Probable Little Tern, Khartoum 30th March 2012
Probable Little Tern, Khartoum 30th March 2012
Probable Little Tern, Khartoum 30th March 2012
Probable Little Tern, Khartoum 30th March 2012
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