possible White-throated Swallow, Lake Naivasha, 23rd November 2012

From: Adam Scott Kennedy <adamscottkennedy@gmail.com>

Date: 2012-11-25 08:59

Subject: possible White-throated Swallow, Lake Naivasha, 23rd November 2012

I've just completed a 16-day birding safari of Kenya for Zoothera Global Birding where we had a good tally of birds including Eurasian Wryneck at Kakamega, Ferruginuous Duck at Limuru Pond and breath-taking views of an Eleanora's Falcon hawking with 6 Eurasian Hobby just overhead near the Tana River Power Station. We missed a few easy target birds too but the group were happy with a tally of 566 species seen and a few more heard-only species.

However, one bird that could trump all of the above, if accepted, was the possible White-throated Swallow photographed at Lake Naivasha on 23rd November. We set off on a boat ride from the LN Country Club at 0630 and very quickly came across a leafless bush full of hirundines. The bird in question immediately caught my eye and I was able to take the two images (attached) of the bird before our boat flanked around the flock. Immediate impressions were of a pale fronted swallow with well-defined breast band, whitish throat and well-defined red spot the forecrown. It was clearly an odd bird but as one of the birds perched just to the left was a Sand Martin (new for the trip) I made sure everyone saw that bird before my mystery swallow went out of sight. It was not until after flock had taken flight that I reviewed the images and realised that the breast band was complete (eliminating Ethiopian Swallow) and the throat was clearly white and not off-white (eliminating a few other hirundines). It seemed that a possible mega had just slipped away!

Looking at the images again, I'm trying to eliminate other possible species;

Angola Swallow - should show sooty underparts, reddish throat and lack a dark breast band.

Wire-tailed Swallow - should show a rufous cap in all ages and lack a complete breast band. Jizz not at all right for this bird.

Ethiopian Swallow - very similar to the mystery bird (esp. red spot on forecrown and whitish belly) but should show an incomplete breast band in all ages and, in good light, a buffish throat although this can be difficult to see at times. Ethiopian is a small swallow and you can see on the wider image that the mystery bird is noticely larger than the Plain Martins nearby, whereas Ethiopian is just 1cm larger than Plain Martin.

Barn Swallow - with so many migrant Barn Swallows around in varying plumages, maybe this is the most likely candidate for the mystery bird (size is right) but there several features that should eliminate it. Adult Barn shows a red forecrown and complete breast-band but should also show a reddish throat. Immature Barns will often show a pale, buffy throat (often showing orange tones at this time of year in East Africa) but in such plumages the forecrown is also very pale. I do not recall ever seeing a pale-throated immature Barn Swallow with such an obvious red forecrown.

About the attached images;

1. poss-wts1 = a cropped image of the original kept wide enough to show the swallow in context with Plain Martins. Not adjusted in any other way

2. poss-wts1a = the same image as above but heavily cropped and slightly manipulated with an increase in sharpness, contrast and colour saturation

3. poss-wts2 = the second image, heavily cropped and slightly manipulated with an increase in sharpness, contrast and colour saturation

According to Stevenson & fanshawe, White-throated Swallow has only been recorded once in East Africa - at Lake Jipe, northern TZ, in July 1957, so any claim of this species here must be given a very tough grilling.

I would be grateful for all considered responses, for and against. I particularly appeal to birders in southern Africa who may have considerable experince with White-throated Swallow.