Identification of Seebohm’s Wheatear in Senegal
Last winter, I had the chance to have a closer look at a species that is relatively little-known, particularly on its wintering grounds: Seebohm’s Wheatear, a former subspecies of Northern Wheatear that was fairly recently (though long overdue it seems) recognised as a full species by many authors, though surprisingly not yet by IOC. These neat little birds have a pretty restricted breeding range, only occurring in the Atlas mountains of Morocco and Algeria. A couple of years ago I had the chance of seeing these birds for the first time, more precisely in May on their breeding grounds at Oukaimeden, birding hotspot incontournable of the Moroccan High Atlas. As such it was particularly nice to meet up with them on their Sahelian wintering grounds a few months later, during our memorable trip up north in January 2018.
Wheatears can be tricky birds to identify, with several species often posing a bit of an ID challenge, and Seebohm’s is no exception. However, nothing much has been written about the identification of first-winters and adults in non-breeding plumage¹, and depictions in standard field guides may be misleading or even incorrect. In an effort to further our knowledge of the species, we thought it may be useful to summarise what we know based on our limited experience with Oenanthe seebohmi in the field here in Senegal, combined with a brief study of available pictures. Note though that by no means is what follows necessarily a comprehensive overview; additions and corrections are most welcome as usual.
A second blog post will focus on the status & distribution of the species.
Identification in winter
While straightforward to recognise in spring, Seebohm’s Wheatear on its Sahelian wintering grounds can be difficult to identify, mainly because they may superficially resemble Desert or Black-eared Wheatear, while young birds and some females may look like Northern Wheatear. We’ll start by reviewing field characters as found in the most relevant literature: mainly the excellent Robins and Chats (Clement & Rose 2015), Nils van Duivendijk’s Advanced Bird ID Guide (2010), and the recently published seminal reference guide by Shirihai & Svensson (Handbook of Western Palearctic Birds: Passerines, 2018). Let’s see how these can be applied to some of the pictures of presumed Seebohm’s taken in winter.
- Size & overall impression are very similar to Northern Wheatear, though it is slightly smaller than that species – something that’s not necessarily obvious in the field unless maybe in direct comparison to nominate Northern; it’s clear though that Seebohm’s definitely doesn’t look larger than Northern as is the case with ‘Greenland Wheatear’ (= ssp. leucorhoa) where the size difference is usually obvious in the field.
- Structure is typical of wheatears and does not appear to be very different from Northern either; the wing is supposedly slightly shorter, though this is not really obvious in the field, several of the pictures presented here actually show rather slender long-winged birds with an important primary projection, rarely giving a more compact appearance. On most pictures presented here we can however verify that the primary projection is slightly less than the length of exposed tertials (Shirihai & Svensson).
- The bill and tail are said to be “rather longer” than Northern, but these differences are again likely of little use in the field, and I’d imagine that there’s some overlap between species – more measurements on museum skins are likely needed to confirm this.
- In all plumages, the black terminal tail band is narrower than in Northern Wheatear (on outer tail feather, ca. one third of the length of the feather is black), though yet again this is not a very useful field character unless good pictures of the tail are obtained.
- Another key difference is that the underwing coverts are entirely black in males, while in females there are pale streaks on dark underwing coverts, unlike in Northern.
Adult and second-year males are generally straightforward to identify in autumn and winter, when they largely retain their distinctive head pattern, only to a limited degree obscured by pale fringes, combined with very pale underparts and “largely greyish or slighly sandy-grey” upperparts. As a result, adult males should be easy to pick out in autumn and winter, despite not showing the crisp black/grey/white plumage typical of spring males. Still, they remain very distinctive and are unlikely to be confused with any other species, such as this one from the end of March on wintering grounds in southern Mauritania, photographed by the late Robert Tovey (Birding for a lark blog):
The two birds below were photographed in Nouakchott by Rob Tovey, at the end of September and mid-October, respectively. Both are clearly males, and while not very grey, I believe both are 1st year birds (note moult limit on first bird). However, ageing of these birds “requires close inspection of moult and feather wear and pattern in wing” (Shirihai & Svensson) and is often not straightforward – more on this below. This bird on Afbid from January near Richard-Toll, photographed by Nik Borrow, clearly shows an adult-type male, with a largely grey crown, mantle and scapulars.
There appears to be some confusion about the plumage of adult females in the literature, with some authors only mentioning that adult females have a “(dark) grey mottled throat” (van Duivendijk), whereas Svensson in the Collins Bird Guide writes that “females and imm. are often inseparable from [Northern] Wheatear unless showing hint of mottled grey throat (rare though)”. Clement & Rose provide illustrations of an adult male and a dark-throated adult female, but don’t bother illustrating typical females, nor do they show any birds in autumn and winter. They do note that females are variable, ranging from closely resembling typical females of Northern Wheatear, to showing brown ear-coverts and having black or blackish-brown lores to chin and throat tipped with buff, grey or sandy colour – thus more resembling the males in head pattern. Not very clear!
Luckily, Shirihai & Svensson are more precise, stating that adult females are “almost identical to ad. f. (and young m.) libanotica Northern Wheatear, and contrary to previous descriptions nearly always lacks dark bib.” Black- or grey-throated females are thus considered rare. They go on to describe the upperparts as “largely pale grey (with limited sandy-brown suffusion) including on crown. Usually has duskier or almost blackish lores and ear-coverts; whitish supercilium often narrow and short, hardly extending to forehead […].”
Here’s a typical female in spring on the breeding grounds at Oukaimeden, and this picture on Afbid is from May at Ifrane. Adult females in autumn are said to be much as in spring but warmer.
The ageing criteria for first-winter birds, according to van Duivendijk, are as in Pied Wheatear [everyone knows these criteria by heart, right?!]: primary coverts with slightly frayed broad white fringes (ad autumn: often narrower and sharply bordered); primaries brown to brown-black often with pointed and worn tips; pale fringes to secondaries complete and cream-coloured; sometimes moult limit visible in greater coverts. There you go, just in case you’d forgotten. Ageing is thus largely based on moult limits, with first winter birds retaining juvenile primaries, primary-coverts and outer greater coverts, whereas in adults these are evenly fresh.
Back to Shirihai & Svensson, who state that first-winter males are “more female-like and rather feature-less, but still approaches fresh ad. m., having greyer upperparts and darker face with exposed black mottling especially on sides and lower throat; warmer below (Variation poorly known and requires more study)”, and that first-winter females have the “least contrasting plumage, with paler face pattern, and browner/duller ear-coverts.”
Let’s put the above to the test on some of our pictures from Senegal!
The following four photographs show three different birds from January; all are presumed to be first-winter males with varying levels of black extent on the face and throat. I initially assumed these to be adult males, but judging by the description of non-breeding males (by Shirihai & Svensson mainly) and compared to some of the pictures presented earlier on and those in Förschler et al., I now tend to label them as first-winter birds – mainly because of the overall sandy-coloured upperparts, mostly lacking grey tones. Again, keep in mind that ageing of these birds can be tricky and is not always possible! In the first bird, note the largely black throat and face appearing rather “smudged”, a fairly large white front merging into a clear whitish eyebrow extending well beyond the eye, and largely pale sand-coloured mantle and scapulars, the latter with a hint of light grey. The wings in the bird below appear relatively contrasted black and white, with extensive white fringes to the secondaries.
In this picture of the same bird, the greyish scapulars and some grey mottling on the back are more apparent:
This one taken earlier that same day in a different location shows a bird with less white on the chin and gives a very “cold” impression, though this is certainly exaggerated by the subdued early morning light. See also this picture of the same bird, as well as the second picture in this post (the one with spread out wings) which may well show the same bird, five weeks later in the same spot. Not sure about sex here – probably a male, but we probably can’t exclude a dark-throated female.
The same goes for this one from last December, taken by Wim van Zwieten near Podor. This bird also has fairly little black on the face but extensive pale fringes to greater and primary coverts as well as to secondaries, suggesting a first-winter male, though again not sure it can safely be sexed. These birds may be mistaken for Desert or Black-eared Wheatear (the black-throated form of which sometimes occurs in Senegal, though it’s probably rare), even by experienced birders.
The next bird gives a very pale impression, with uniform light sandy upperparts and a white lower breast, flanks, belly and vent. The upper breast are warmer tinged with a buffish wash extending down from the ear coverts, and so are the undertail coverts. The black or dark brown loral stripe is reminiscent of Isabelline Wheatear, but it has a narrow yet distinct supercilium both in front and behind the eye and has a different ‘jizz” and wing pattern than Isabelline. I’ve concluded that it’s a first-winter female, but as always would stand happy to be corrected. Either way, the very white underparts and pale upperparts stand out and should immediately point to Seebohm’s.
Of course, identifying a female or 1st winter bird in a vagrant context is something else. While not necessarily impossible, it will require a combination of characters as well as proper photographic documentation of underwing and tail pattern in particular. There have been at least two suspected birds in autumn in the UK but which could not be confirmed as definite Seebohm’s (read up more on these tricky birds here on Birding Frontiers). The first confirmed sighting for NW Europe was of a male in May 2017 in the Netherlands, a typical case of “overshooting” by North African or Mediterranean species during spring migration. Elsewhere in Europe, the species has been reported as a vagrant from Gibraltar, Italy, Malta, the Canary Islands.
Stay tuned for part II!
– Bram, with thanks to Frédéric, Simon, and to Wim for the use of his picture. And most importantly, a posthumous tribute to Robert Tovey who in a short few years made valuable contributions to our knowledge of birds in Mauritania, before unexpectedly passing away in September last year.
¹ Note (19.2.19): The only exception is actually a remarkable paper written by Mayaud in… 1951, in the French journal Alauda (19:88-96): Le plumage prénuptial d’Oenanthe oenanthe seebohmi (Dixon), in which the author provides a detailed description of birds in non-breeding plumage.