Here in Abu Dhabi we are just getting to the end of another spring migration season and, as usual for the second half of April and early May, there has been a fine sprinkling of Common Nightingales to enjoy. With a general lack of low cover in much of the city, these ground-feeding birds are often very easy to observe and study here. The traditional task locally is to hunt through them in search of the odd Thrush Nightingale (rare but annual in the UAE and just about frequent enough to make it well worth checking carefully every last Luscinia). It is actually rather easy to pick out the odd Sprosser from almost all Common Nightingales occurring in the UAE and this is the take-home message of this short note – the majority of Common Nightingales on passage in both spring and autumn are the easternmost subspecies L. m. golzi (‘Eastern Nightingale’) and they look strikingly different from both Thrush Nightingale and nominate Common Nightingales occurring in Europe. My first ever Eastern Nightingale, in a public park in Abu Dhabi in April 2005, was a real eye-opener and all those I have seen since, including a few in the same park this week, have looked equally striking. Eastern Nightingale has reached the UK on three occasions in autumn and, looking almost as distinctive in even worn plumage in spring, is certainly fair game as a late May or early June overshoot in a manner akin to, say, White-throated Robin. Ok, finding one won’t have quite the same wow factor as an Irania but you’ll have nailed something at least as rare (and rather more intellectually demanding…)
A selection of images of Eastern Nightingales taken recently in the UAE in spring is presented below. European birders familiar with the nominate form that I have observed these birds in the field with are frequently as bowled over as I first was by their distinctiveness, which stems from a whole suite of characters. In fact, on an initial cursory glimpse, due to both plumage and tail movements (see below) it is even possible to pass Eastern Nightingale off as a Rufous-tailed Scrub-Robin! I’ve done it myself – and this similarity was noted as long ago as 1991 by fortunate observers on Spurn!
Above © Oscar Campbell – Abu Dhabi, May 2014
Below: © Huw Roberts – UAE, May 2011
Salient plumage features, in rough order of prominence and importance are highlighted below:
- The whole upperparts are invariably strongly grey-tinged, giving an overall rather sandy effect, with marked contrast between this and a rather pale, diluted rufescent tail and uppertail coverts. On some birds, even in spring, pale greyish tips to the rump feathers create a noticeably scaly effect.
- There is obvious pale greyish or even almost whitish fringing on the tertials and greater coverts, the latter regularly forming a vague but definite wingbar. The median coverts often show rather obvious pale fringes too, although these can be often rather diffuse, especially in spring.
- Primary tips frequently have sharp, neat white fringes and, on good photos, often eight primaries can be counted quite easily (perhaps because p2 – numbering ascendently – is fractionally longer than p3 whereas these two tips seem generally to fall together on many nominate birds)
- A variably distinct pale loral area, sometimes running back over the eye as a diffuse supercilium - nominate birds looks markedly bland and plain faced in comparison, although this character can seem to melt away as the bird turns its head.
- There is sometimes a particularly distinct grey tinge to the nape. Coupled with any supercilum, this may isolate the crown and forehead as a slightly warmer cap and it may also smear onto the breast, forming weak greyish breast band that isolates the paler throat. The overall effect can then resemble the classic pattern of Thrush Nightingale but is much more washed out, with the grey tones weaker and smooth, entirely lacking any scaling or dingy smudging effect.
Appearance in autumn is only slightly different from spring. Feathers fresh from the post-juvenile or post-breeding moult on the breeding grounds have even more obvious pale fringing and the two-tone contrast between tail and rump / mantle may be even more striking. Below is a particularly co-operative individual from Abu Dhabi in October 2013.
© Oscar Campbell Abu Dhabi October 2014
One final striking character for Eastern Nightingale is their addiction to near-continual tail movements. These are emphasised by the length of tail (which barely, if at all, overlaps with nominate birds). Individual Eastern Nightingales, watched for prolonged periods over several days in Abu Dhabi sometimes go through periods of rather subdued, limited tail movements but they are the minority – most frequently the tail is in near continual motion. Movements include deliberate and sometimes continual lateral waving, sometimes with a sudden partial splaying of the tail when the tail is well to one side and also regular vertical abrupt flicks where the tail briefly rises high over the back. Again, sometimes at the maximum point of the downstroke there may be a sudden pulse or splay as the tail is partially opened. These movements are exhibited by retiring birds skulking in dense tangles, by birds foraging openly on the ground and even by birds resting and sunning on low, exposed perches.
© Oscar Campbell, Abu Dhabi, May 2014
A short note in BB (2011; 104:41 ) described how these movements will rapidly allow the distinction of Common Nightingale from Thrush Nightingale even on a mostly obscured view but there is also a chance that they are a very good indication of Eastern versus nominate Nightingales. Nominate (or, perhaps more likely africana) Common Nightingales do occur in the UAE but not frequently (see this bird for example) and as yet have not been studied with regard to tail movements. Observations from Birding Frontiers readers from western Europe on tail movements (or otherwise!) of Common Nightingales would be most welcome. At this stage a good rule of thumb might be that any migrant Nightingale in Europe showing deliberate, prolonged lateral tail waving and pulsing demands a thorough examination, no matter how skulking or how dense the gorse or Suaeda!
The breeding range of Eastern Nightingale extends from eastern Iran northwards and eastwards to western China. It appears to be genuinely rare on migration through the western Arabia and the Levant, with only one record from Kuwait up to 2012 and a mere three in Israel by 1996. However it makes a good majority (maybe a vast majority) of passage Common Nightingales in the UAE and is also frequent in Oman – singing birds are easy to find in Musandam, northern Oman in April and the sometimes occur at amazingly high densities in Dhofar, southern Oman in October – lush hotspots such as Ayn Hamran and Wadi Darbat may be full of their song then. A small selection of excellent images from Oman is available here. Combining its frequency on passage in eastern Arabia with an extensive breeding range and a long-distance migration to east Africa, more records for Europe have got to be forthcoming!
Acknowledgements I would like to think Mark Smiles, Gaell Mainguy and Huw Roberts for useful and stimulating discussions concerning whilst observing Eastern Nightingales recently in the UAE. Also thanks to Huw for providing a number of useful images, including the two that are presented above.
First hyperlink: this bird http://www.smugmug.com/gallery/5655608_q6yKb#!i=359545879&k=BWTpn9N&lb=1&s=A
Second hyperlink here http://www.birdsoman.com/Birds/130-Thrushes/CommonNightingale/CommonNightingale.htm