Another visitor from North America showed up recently at Technopole: a superb adult Laughing Gull (Mouette atricille) was found by Miguel Lecoq and Ignacio Morales over the Easter weekend. First seen on 21.4, it was still present two days later when it was also heard calling. Amazingly, later that same week (25.4), Miguel found an immature (2nd year) in the same place!
Identification is pretty straightforward, the main field characters being nicely visible here: dark grey mantle, almost entirely black outer primaries, narrow white trailing edge to secondaries and tertials, back hood with white “eye lashes”, fairly long dark crimson red bill, and rather long dark red to blackish legs. The young bird is also very distinct and is relatively easy to pick out amongst the numerous other gulls that are present at Technopole at the moment: Slender-billed Gulls mostly, but also Grey-headed Gulls (the immatures of which superficially resemble Laughing Gull), and still some Black-headed, Audouin’s and Lesser Black-backed Gulls (Goeland railler, Mouettes à tête grise et rieuse, Goelands d’Audouin et brun).
Proper rare bird record shot:
This is the fourth American species to be seen in Senegal in less than two weeks, once again highlighting the potential of the country to find vagrant gulls and waders: the overwintering Lesser Yellowlegs (Chevalier à pattes jaunes) was last seen on 8.4, followed by a 2nd year Franklin’s Gull (Mouette de Franklin) on 13.4, the American Golden Plover (Pluvier bronzé) from Palmarin (15.4), and now Larus atricilla. And this is by just a small handful of active observers… just imagine what else there is to be found, if only there were more birders here.
There are just five previous records of Laughing Gull:
- An adult in the Saloum delta on 18.3.85 (Dupuy, A.R. (1985) Sur la présence au Sénégal de Larus atricilla. Alauda 53. Two years earlier, a possible sighting in the same place of a bird apparently paired with Grey-headed Gull, could not be confirmed and should thus be ignored.
- An adult at Guembeul (near Saint-Louis) on 12.1.95 (Yésou P., Triplet P. (1995) La mouette atricille Larus atricilla au Sénégal. Alauda 63)
- A 2nd winter in the Saloum delta on 28.12.05, see picture below (A. Flitti; Recent Reports, Bull. Afr. Bird Club 13)
- One flying past the Ngor seawatch site on 7.10.08 (P. Crouzier, P. J. Dubois, J.-Y. Fremont, E. Rousseau, A. Verneau; Recent Reports, Bull. Afr. Bird Club 16)
- An adult at Saint Louis on 10.1.14; a 2nd winter possibly also present (M. Beevers; Recent Reports, Bull. Afr. Bird Club 21)
Elsewhere on the continent, there are records from Morocco, Mauritania, The Gambia, Guinea-Bissau (first records is yet to be published), and possibly elsewhere – most recently, an imm. photographed at the Bijol Islands in Gambia in December 2018. It’s an annual vagrant to western Europe, even in unexpected locations such as on this lake in the Swiss Alps where an adult overwintered in 2005/2006:
Unlike Franklin’s Gull, which has been recorded in all months except for November, with most records in May, July and August, Laughing Gull is obviously a species that is more to be expected in winter, with all records so far occurring between October and April.
Other good birds found during Miguel’s frequent visits these past few days include two other additions to the Technopole list: Golden Oriole on 25.4 (Loriot d’Europe), and Pallid Swift on 23.4 (Martinet pâle). A late Mediterranean Gull (Mouette mélanocéphale) was also a good record, as was the count of 606 Sanderlings.
The site list now stands at 237 species. Which one will be next?
I wrote the preceding paragraphs yesterday, and since then I’ve been – at long last – back to Technopole, as I was up north last weekend and travelling abroad for work this past week. Well, we got the answer: species number 238 is Plain Martin (also known as Brown-throated Martin; Hirondelle paludicole). We had a single bird feeding over the water – often at close range – along with a couple of Barn Swallows (Hirondelle rustique) and several Little Swifts (Martinet des maisons), nicely showing its features. This is a rarely reported species from Senegal, and as it turns out the first eBird observation for the country! It’s rather patchily distributed throughout West Africa, being more common in Morocco, East Africa, and Southern Africa. Considered a non-breeding visitor to Senegal and Gambia, I could only find six old records from Senegal: Morel & Morel list four, followed by one in Jan. 1992 in the Djoudj and one from Mekhe in August 1992. Last year, Bruno Bargain found several at Kambounda (Sédhiou, Casamance), on 2.12.18, but other than those there do not seem to be any recent observations. Very nice sighting and an unexpected addition to my Senegal list – and a cool lifer for Miguel!
Alas no Laughing Gull this morning, but we did see the Frankin’s Gull again. Also another Pallid Swift, as well as new sightings of a colour-ringed German Gull-billed Tern (Sterne hansel) and a Norwegian Common Ringed Plover (Grand Gravelot), plus now two different Med’ Gulls. Let’s try again on Wednesday morning, who knows maybe the gull will be back. It may actually have been around for a few weeks now, as there was a possible sighting at Technopole on March 30th. It’s quite possible that the adult is hanging out by the harbour or elsewhere in the baie de Hann or even Rufisque, and will show up again at Technopole.
A recent early morning visit to the Trois-Marigots area, just outside Saint Louis in the lower Senegal delta, quickly turned into a proper gallinule fest, with dozens – hundreds probably! – of rallidae: Moorhens, African Swamphens, Black Crakes, and even a few of the much hoped for Allen’s Gallinule. No crakes this time round, but all in all a pretty spectacular sight in a great setting. Below are a few images taken during our visit, all but the last one taken from the Tylla digue which crosses the second of the the Trois-Marigots. Vieux and I mainly birded a stretch of just a few hundred meters for the first couple of hours, with new birds showing up all the time.
With habitat like this, what would you expect?
Rails of course, but also African Pygmy-Goose, Purple Heron, Black Heron, Little Bittern, African Fish-Eagle, Marsh Harrier, various Acrocephalus warblers, Winding Cisticola, Zebra Waxbill, and so on.
Allen’s Gallinule is pretty local in Senegal, being most regularly reported from Djoudj and from Trois-Marigots, though it also occurs in Casamance and probably elsewhere (still waiting for it to show up one day at Technopole!). We saw at least two adults, including one with a bright blue frontal shield. The second bird, pictured below, was somewhat duller but the obvious red eye indicates that it is also in breeding plumage, making it likely that the species breeds here at Trois-Marigots.
And here’s that obligatory Pygmy-Goose picture, which I have to say I was quite pleased with:
This one a bit less so, but nevertheless, always great to get a reasonable picture of a nervous warbler that just would not sit still… While most wintering warblers are long gone by now, there were still quite a few of these Sedge Warblers around, plus several Eurasian Reed Warblers, two Willow Warblers, and just one Bonelli’s Warbler. For the most part these are probably birds from the northern part of their breeding range.
Complete eBird checklist here, plus this one from the now bone-dry savanna between the first (also dry by now) and second marigots: Chestnut-bellied Sandgrouse, Temminck’s Courser, Cut-throat, Pygmy Sunbird, etc. For more on Trois-Marigots and its crakes – including the rarely seen Little Crake – see this post, and of course many other notes by Frederic Bacuez on Ornithondar.
A brief visit to the Lampsar near Makhana village, on the opposite side of the route nationale, paid off with quite a few additional species such as fly-over Glossy Ibises, Collared Pratincoles, several waders including two Little Ringed Plovers, and most notably a small colony of Black-winged Stilts, with at least four birds incubating. There were probably several more, given that some of the nests were relatively well concealed as can be seen on the picture below. Checklist here.
Staying on our swamp theme, here are a few more pictures from the Easter weekend which we spent at Zebrabar at the Langue de Barbarie national park. The Saint Louis STEP (sewage farm) was even more smelly than usual, but as always held some good birds such as this River Prinia and Greater Painted Snipe, two species that were also encountered at Trois-Marigots.
Finally, I should mention that Vieux recently found Senegal’s 6th or 7th Lesser Jacana, more precisely at the Lampsar lodge on March 16th. He’d found the previous one just last summer during a waterbird count near Ross Bethio on July 15th. The species is probably a fairly regular yet scarce visitor to Senegal, but its precise status is yet to be defined. Once again Vieux shows that he’s one of the most skilled – and most active – birders in the country!
Quick post to report yet another American vagrant, after the Franklin’s Gull from last Saturday and the Lesser Yellowlegs from just a week ago, both at Technopole.
This morning at Palmarin in the western Saloum delta, I found an American Golden Plover (Pluvier bronzé), likely a second year bird, feeding on the edge of a shallow lagoon together with a few other waders. It’s almost getting a bit of a standard spring sighting here in Senegal: this is the third consecutive year with records in April, and the species has been near-annual since 2012. Prior to this only three records were known, though it’s not clear whether this reflects a true increase in the number of “AGPs” that make it to West Africa or just a result of increased observer coverage – probably the latter. The Palmarin bird brings the total to 14 records involving at least 17 birds.
As can be seen in my hazy pictures below, the bird stood out mainly thanks to its very white supercilium extending behind the ear coverts, the dark smudge across the breast, and of course long wings extending well beyond the tail tip. As it flew a short distance, I could clearly see the greyish underwing.
The same small lagoon just north of Ngalou village also held quite a few Slender-billed Gulls and several Caspian, Royal and Sandwich Terns (+ one Lesser Crested), six Avocets, three Black-tailed Godwits and a few other waders, though generally there aren’t loads of birds around at the moment (which is all relative of course: far out in the lagoons, there were hundreds of Little Stints and other small waders, just very far out… and at Diakhanor about a dozen Bar-tailed Godwits were seen).
Unlikely that anyone would go out to twitch the plover, but you never know so here’s a Google Maps link to the precise location where I saw the bird.
Besides the waders, a few remaining Lesser Black-backed and Audouin’s Gulls as well as two small groups of Barn Swallows, a couple of Yellow Wagtails and a few Western Olivaceous Warblers were the only other northern migrants still around.
Below are a few pictures of other species seen during the 24 hours we spent at Palmarin.
Let’s see if this spring any American Golden Plovers turn up at Technopole again…
April is Tern month!
From mid-March into May, lots of terns pass through Dakar on their way back home from the wintering grounds further south – some as far as South Africa! – and the first half of April is definitely peak time for many species. When conditions are right, literally thousands of these elegant birds may pass through on a single day, and sites such as Technopole can hold several hundreds of birds at any one time. So much that in the past week, I’ve had the chance to see 12 out of the 14 tern species that are known to occur in Senegal, the only ones missing being Bridled and the rare Sooty Tern.
On Monday 8.4 at Technopole, decent numbers of terns were about, mainly Sandwich Tern (+300, likely quite a bit more) with a supporting cast of the usual Caspian and Gull-billed Terns (the former with several recently emancipated juveniles, likely from the Saloum or Casamance colonies), but also several dozen African Royal Tern, a few Common Terns, at least two Lesser Crested, and as a bonus two fine adult Roseate Terns roosting among their cousins. And as I scanned one of the flocks one last time before returning back home, an adult Whiskered Tern in breeding plumage, already spotted the previous day by Miguel. I managed to read four ringed Sandwich Terns but far more were wearing rings, but were impossible to read.
Yesterday 13.4, we went back to our favourite urban hotspot mainly in order to see if we could read some more of these rings. The main roost is close to the northern shore of the main lagoon, quite close to golf club house, which makes it possible to get close enough to the birds to read most rings. We saw most of the same tern species (except Roseate), with the addition of a fine moulting White-winged Tern and a small flock of Little Terns migrating over our heads. The first colour-ringed bird we saw was actually a Gull-billed Tern, but not the usual Spanish bird (“U83”) ringed in 2009 and seen several times herein the past three winters. This bird was even more interesting, as it was ringed in the only remaining colony in northern Europe, more precisely in the German Wadden Sea. Awaiting details from the ringers, but it’s quite likely that there are very few (if any!) recoveries of these northern birds this far south. It may well be the same bird as one that we saw back in November 2018 at lac Mbeubeusse, though we didn’t manage to properly establish the ring combination at the time.
So, back to our ring readings: all in all, we managed to decipher an impressive 14 Sandwich Tern rings – blue, white, yellow & red! – of birds originating from no less than four countries: Ireland, UK, Netherlands, and one from Italy (to be confirmed). Most of these are chicks that were born in summer 2016 and that logically spent their first two years in the Southern Hemisphere, and are now returning back to their breeding grounds for the first time. In addition, a Black-headed Gull with a blue ring proved to be a French bird ringed as a chick in a colony in the Forez region (west of Lyon) in 2018, while a Spanish Audouin’s Gull was a bird not previously read here. I’ll try to find some time to write up more on our ring recoveries, now that my little database has just over 500 entries!
Others local highlights from these past few days are the Lesser Yellowlegs still at Technopole on 8.4 (but not seen yesterday… maybe it has finally moved on), also a superb breeding plumaged Bar-tailed Godwit, still a few Avocets, plenty of Ruff, Little Stint, Sanderling, Curlew Sandpiper and Dunlin, many of which in full breeding attire. And on 13.4, once again a Franklin’s Gull, but also a rather late Mediterranean Gull and what was probably the regular adult Yellow-legged Gull seen several times since December. Three Spotted Redshanks were also noteworthy as this is not a regular species at Technopole. The Black-winged Stilts are breeding again, and the first two chicks – just a couple of days old – were seen yesterday, with at least two more birds on nests; a family of Moorhen was also a good breeding record.
Full eBird checklist from 13.4 here.
Earlier this week at the Calao was just about as good in terms of tern diversity: again the usual Sandwich Terns which are passing through en masse at the moment, with some LCT’s in the mix, several dozen Common Terns and the odd Roseate Tern hurriedly yet graciously flying past the seawatch spot, and of course more Royal Terns en route to Langue de Barbarie or Mauritanian breeding sites, a lone Caspian Tern, and this time round an even less expected White-winged Tern (and just two Black Terns). Oh and also the first Arctic Tern of the season! The first birds in spring are typically seen at the end of March or first half of April; earliest dates (2015-2018) are 16.3.18 and 25.3.16. The numbers of migrating terns were really impressive here on Saturday 6.4: a rough estimate puts the number of Sandwich and Common Terns passing through at 500 and 1200, respectively, in just two hours.
At Ngor, regular morning sessions have yielded the usual Pomarine and Arctic Skuas, Northern Gannets, as well as a handful of Cape Verde Shearwaters feeding offshore on most days. Sooty Shearwaters passed through in good numbers on 6.4, while last Friday (12.4) was best for Sabine’s Gull: 73 birds in just one hour, so far my best spring count. Also several Long-tailed Skuas and the other day a South Polar or (more likely) a Great Skua was present, a rare spring sighting. All checklists for the recent Calao counts can be found on this eBird page.
Following the addition of Turati’s Boubou (Ziguinchor, October 2018) and Willcocks’s Honeyguide (Dindefelo, January 2019), another scarce Afro-tropical species was recently added to the avifauna of Senegal: Cuckoo Finch, Anomalospiza imberbis (in French: Anomalospize parasite). Three birds were found on 17 February in moist grassland north of Oussouye in Basse-Casamance, by Bruno Bargain, Gabi Caucal and Adrien de Montaudouin.
While not necessarily straightforward in the field, their identification could be confirmed based on a few pictures that the team were able to obtain: small, compact drab-yellow finch with a short yet deep conical bill, short tail with pointed central rectrices, pale central crown stripe, small beady black eye, long pale claws. The two-toned bill (pale base of lower mandible contrasting with darker upper mandible) is typical of juveniles, while the yellowish underparts and throat suggest that this bird is a young male.
Several birds were seen again a couple of weeks later by Bruno, including two singing males: it’ll be interesting to see whether this little group is resident here and whether more will be found in nearby locations in coming months… there’s definitely a lot of potential, with quite a bit of suitable habitat elsewhere in the area.
As with the boubou, the discovery of this species in SW Senegal was to be expected given that it has been seen several times in recent years just across the border in Gambia, prompting me to include the Cuckoo Finch on our list of the birds of Senegal with a question mark (“presence to be confirmed”) when I initially compiled the list last year. The checklist is accessible through this new page that was recently added to the Resources section of this website. Cuckoo Finch is species number 679 on the national list! (though to be fair, this includes five for which definite proof is lacking, and which remain to be confirmed)
Cuckoo Finch is indeed a widespread yet local and uncommon species throughout Sub-Saharan Africa, and particularly in West Africa its status and patchy distribution remain poorly known. It occurs in Sierra Leone, Liberia, Cote d’Ivoire as well as in southern Mali, and probably also in Guinea and Guinea-Bissau though as far as I know there are no records in these two countries. In Gambia it was first recorded in 1969, on 24 September by O. Andrew. The only further details I found on this record are in Morel & Morel (1990), who state that “about a dozen were seen well in Sept.-Oct. 1969 near Banjul”. It then took more than 40 years for the next record to be obtained, more precisely at Kartong Bird Observatory where three birds were caught and ringed on 24 Feb. 2013; in subsequent years the species was again caught or seen on a few occasions at KBO, at most 14 birds on 27 April 2014, and again several birds in May-October 2017. All were non-breeding or young birds, with no evidence of local breeding (O. Fox, J, Cross).
Given these more or less regular sightings at Kartong, which lies right on the border with Casamance, it would make sense if the species were also present around Abene, Kafountine, Diouloulou or other nearby locations. We’ll try to explore some of these sites in coming months, particularly during the breeding season, i.e. during the rains. The finders are currently writing up a note to formally publish their discovery.
Also known as Parasitic Weaver, the “unusual finch” as per its scientific name is the unique representative of its genus, having previously been linked to weavers and even canaries. It is now included in the viduids as it is most closely related to the whydahs and indigobirds (see e.g. Lahti & Payne 2003). Just like these birds, it is a brood parasite, laying its eggs in nests of cisticolids (cisticolas and prinias), apparently up to c. 30 eggs per season (!), in batches of 1-4 eggs per “set”. Zitting Cisticola and Tawny-flanked Prinia may be the most likely host species in Senegal and Gambia.
There’s of course a lot more to be said about this peculiar songbird, for instance how females adopted a mimetic strategy to fool its hosts: Feeney et al. (2015) demonstrated how “female Cuckoo Finch plumage colour and pattern more closely resembled those of Euplectes weavers (putative models) than Vidua finches (closest relatives); that their Tawny-flanked Prinia hosts were equally aggressive towards female Cuckoo Finches and Southern Red Bishops, and more aggressive to both than to their male counterparts; and that prinias were equally likely to reject an egg after seeing a female cuckoo finch or bishop, and more likely to do so than after seeing a male bishop near their nest.” Fun fact: I happened to meet Claire Spottiswoode, one the co-authors of the paper and specialist of brood parasites, on their southern Zambian study site while they were conducting field work in March 2013… but I failed to find any Cuckoo Finches!
For some more on parasitic birds, here’s a good start.
Plenty of other good birds were seen in Casamance last month, including the first White-tailed Alethe (Alèthe à huppe rousse) in many many years, Lesser Moorhen (Gallinule africaine), Ovambo Sparrowhawk (Epervier de l’Ovampo), Bluethroat (Gorgebleue à miroir), Forbes’s Plover (Pluvier de Forbes), European Golden Plover (Pluvier doré), Yellow-legged & Kelp Gulls (Goélands leucophée et dominicain), and quite a few more scarce species. With a bit of luck, Gabi and Etienne will find some time to write up the highlights of what was once again an epic trip across Senegal.
Meanwhile in Dakar, seabird spring migration is in full swing, with the first Long-tailed Skuas, Sooty Shearwaters, Roseate Terns and so on passing through in recent weeks (Labbe à longue queue, Puffin fuligineux, Sterne de Dougall). More on this in due course.
Many thanks to the finders for allowing me to write up this post, and to Olly Fox for providing info on the Kartong records.
We’re continuing our little series on the status of some lesser known passerines that spend the winter in Senegal. This time round we’re looking at Iberian Chiffchaff (Pouillot ibérique), yet another drab songbird that can be tricky to identify unless of course it’s singing. We won’t go much into its identification in this post; a lot has been written on the topic, though unfortunately the standard West Africa field guides lack sufficient detail and may oversimplify the matter somewhat. In addition, few if any of the local guides really know how to identify the species in the field, and not all visiting birders pay much attention to these LBJs.
There are a few subtle differences in plumage, but generally it’s not easy to identify these birds on plumage and “jizz” alone.. so maybe it’s useful after all to summarise key characteristics here. Lars Svensson, in what is still one of the main reference papers on Iberian Chiffchaff identification (2001), neatly listed the following field characters in comparison with Common Chiffchaff:
- As a rule, the entire upperparts of ibericus are purer moss green than on Common Chiffchaff, lacking the brown tinge on crown and mantle usually present in collybita in freshly moulted plumage in early autumn a very slight brownish tinge can be found on the greenish upperparts of some Iberian Chiffchaffs
- More tinged yellowish-green on sides of head and neck, and has no buff or brown hues at all, or only very little of it behind the eye and on ear-coverts. The breast is whitish with clear yellow streaking
- Typically, has vivid lemon yellow undertail-coverts, contrasting with a rather whitish centre to the belly
- Supercilium on average more pronounced and more vividly yellow, particularly in front of and above the eye
- On average, the legs are a trifle paler brown on Iberian than on Common Chiffchaff, though many are alike
- Bill is very slightly stronger [though I find this one of very little use in the field!]
Clearly these are mostly subtle differences and when identifying on plumage alone, a combination of characters should typically be used. Confusion with Willow Warbler is not unlikely, even by experienced birders, and I’m assuming that at least some Iberians are noted as Willow Warbler, especially in mid-winter in northern Senegal when Willow Warbler should in fact be rare, as it winters chiefly in the forest zone further south. The longer wings, pale underparts and paler legs can indeed result in striking similarities between Willow and Iberian. A good pointer to separate these two is that the latter typically dips its tail while feeding, whereas Willow, Warbler characteristically flicks its wings while moving its tail sideways.
The two pictures below were taken by Frédéric Bacuez near Saint-Louis, on 18.4.16 (top) and 20.1.13 (bottom), and while it’s probably impossible to be certain, I do tend to believe these are Iberian Chiffchaffs.
The vocalisations on the other hand are far more reliable and are indeed always ideal in order to confirm an Iberian Chiffchaff, particulary the song. While there’s some variation and there may be some “mixed singers”, the difference with Common Chiffchaff is usually obvious (though maybe a bit less so on this one from Wassadou). It’s worthwhile pointing out though that besides the quite distinctive song, a good yet undervalued criterion is the call of the species – see this nice summary on the Turnstones blog (and also Collinson & Melling 2008, who state that the call “in sharp contrast to that of Common Chiffchaff, is downwardly inflected, from 5 to 3 kHz, transcribed as ‘piu’ or ‘peeoo’, perhaps reminiscent of the call of Siskin” – now compare with my recording from Technopole (same bird as in the song recording): I wouldn’t say this sounds like a Siskin – and even less like a Bullfinch! – and at 3.5-6 kHz the frequency is clearly a bit higher as can be seen on the sonogram below (click to enlarge).
Status & Distribution in Senegal
Up to not so long ago, most authors considered Iberian Chiffchaff to be a resident or partial migrant, mostly due to lack of reliable identification criteria at the time. Svensson (again!) provided the most comprehensive overview of our knowledge of the wintering areas in his 2001 paper, concluding that it is “a long-distance migrant which winters primarily in tropical Africa“. This assumption was however based on very few specimens and even fewer reliable field observations. One of these is of a bird “singing like an Iberian Chiffchaff” by Yves Thonnerieux from northern Ghana, and the only two specimens from wintering grounds are from Mali in 1932 (Segou) and 1955 (Bamako); both were found by Svensson in the museum of natural history in Paris (MNHN). A third specimen was collected in January 1955 in Tunisia, suggesting that some birds may winter north of the Sahara; Svensson also showed that the species is present during spring migration in Morocco (at least late March – early April).
With increased “observer awareness” and better reporting systems, recent years have seen a clear increase in field observations from West Africa, described further below. Combined with the absence of any winter records from the Iberian peninsula, I think it’s quite well established now that indeed most if not all Iberian Chiffchaffs winter south of the Sahara.
To further refine its status in West Africa, we turn to our usual suspects: Morel & Morel provide a single record, presumably obtained by themselves, of a singing bird at Richard Toll on 22-24.2.87 (this is probably the unpublished record “from tropical Africa” that Svensson refers to). This can safely be assumed to be the first published record for Senegal; identification was apparently largely based on song since they write that they compared the song with recordings by Claude Chappuis. It’s quite easy to miss out on this observation though, as ibericus (or brehmi as it used to be known) is only referred to in the annex of Les Oiseaux de Sénégambie (1990), as their sighting was obviously too recent to be included in the near-final manuscript of their book. Of course, the species was at the time still considered to be “just” a subspecies of Common Chiffchaff. Rather curiously, the Morels refer to a significant proportion of Scandinavian Common Chiffchaffs (ssp. abietinus) – up to half! – though we now know that these populations tend to winter in eastern Africa, heading in a south-easterly direction in autumn. Could it be that these were actually Iberian Chiffchaff rather than abietinus?
Moving on, Rodwell and colleagues (1996) refer to three records of calling (singing?) birds in the Djoudj NP in Jan 1990, Jan 1991 and Feb 1992. Sauvage & Rodwell (1998) do not provide any additional records: up to the mid-nineties, ibericus was obviously still considered a rare to scarce winter visitor to northern Senegal. More than a decade later, Borrow & Demey still consider the species’ distribution in Senegal as “inadequately known”, and their map only shows the lower Senegal valley.
As is the case with quite a few other little known taxa that were recently elevated to species rank – think Moltoni’s Warbler, Seebohm’s Wheatear, Atlas Flycatcher – these past few years our knowledge has greatly increased, and it is clear that Iberian Chiffchaff is indeed quite frequent in northern Senegal. Recent reports mainly come from the Djoudj NP – obviously a key wintering site, with decent densities – and from around Richard Toll and Saint-Louis (e.g. Bango, Trois-Marigots, Langue de Barbarie, and see picture above). There are however a number of recent records elsewhere that suggest that the species is more widespread: last winter I was lucky to find a singing bird at Technopole which is thought to be the first record from Dakar; there are also a few reports from the Somone lagoon, though not sure that these are reliable (I have suspected the species here before, but never been able to confirm based on call or song). Rather intriguingly, the species was also seen several times along the Gambia river at Wassadou these past two years: first in December 2017, then more than two months later at least one singing bird that we found on 24.2.18, and again this winter (7.1.19). Finally, another singing bird was reported near Kounkane, Velingara, on 28.1.18 (G. Monchaux) – to our knowledge the first record from Casamance. The observations in these southern locations suggest that the species is more widespread and that it can turn up anywhere in Senegal.
In Mauritania, it appears that up to recently the only records were obtained during extensive field work conducted by the Swiss Ornithological Station, with several birds captured both in spring and in autumn 2003 (Isenmann et al. 2010). There are several more recent reports from around Nouakchott mainly, presumably of birds passing through. In addition to the two aforementioned specimens from Mali, the only other record from that country that I’m aware of is of a singing bird that I recorded in a hotel garden in Bamako, where it was singing for at least a week in January 2016. Burkina Faso should also be part of the regular range, though there again there are just a couple of records, most recently a singing bird reported by van den Bergh from the Bängr-Weeogo park in Ouagadougou in December 2011.
The Xeno-canto range map, which is largely based on BirdLife data, is probably the most accurate when it comes to the winter range (though not for the breeding range, the species being absent from most of central and eastern Spain). It should also include all of northern Senegal, or at a minimum, the lower and middle river valley, particularly the Djoudj NP which is omitted from the map below. I’m not sure that the species has been reliably recorded from Gambia even though there are several unverified observations on eBird. Further north, there are several winter records from Western Sahara between early December and early February, mainly at coastal sites (Bergier et al. 2017), suggesting that not all Iberian Chiffchaffs cross the Sahara. Spring migration is noted from mid-February to mid- or end of April.
Iberian Chiffchaff should be present in Senegal and generally throughout its winter quarters from about October to early or mid-April; the earliest observation I could find is one of a bird reported singing east of Richard Toll on 27.10.15. A Danish group reported two birds in Djoudj in early November 2017, but other than that almost all records are from December – February during the peak orni-tourist season.
Paulo Catry and colleagues (including our friends Miguel and Antonio!) showed marked differential distance migration of sexes in chiffchaffs, with females moving further south than males. Their study did not distinguish between Common and Iberian Chiffchaff, but because south of the Sahara (Djoudj mainly), sex-ratios were more male-biased than predicted by a simple latitude model, their findings suggest that among the chiffchaffs wintering in West Africa, a large proportion is composed of Iberian birds, providing further support that these birds are long distance migrants. The ringing data from Djoudj also showed that chiffchaffs display differential timing of spring migration, with males leaving the winter quarters considerably earlier than females [typically, male migrant songbirds arrive a little earlier on the breeding grounds than females, presumably so they can hold and defend a territory by the time the females arrive].
Finishing off with some essential ibericus reading…
- Collinson & Melling, 2008. Identification of vagrant Iberian Chiffchaffs – Pointers, pitfalls and problem birds. British Birds 101.
- Svensson, L. 2001. The correct name of the Iberian Chiffchaff Phylloscopus ibericus Ticehurst 1937, its identification and new evidence of its winter grounds. Bull. B. O. C. 121.
La littérature disponible pour l’identification des oiseaux d’Afrique de l’Ouest a longtemps été très limitée, et ce n’est que depuis 2002 et la parution du guide Birds of Western Africa de Borrow et Demey que ce manque a été en grande partie comblé. Une deuxième édition de ce guide est sortie en 2014, ainsi que des traductions en français de ces ouvrages (Guide des oiseaux de l’Afrique de l’ouest en 2012 suivi de Oiseaux de l’Afrique de l’Ouest en 2015). Deux déclinaisons nationales de ce guide ont été publiées, à savoir Birds of Ghana (2010) et Birds of Senegal and the Gambia (2012) qui est le guide le mieux adapté pour l’ornithologue visitant le Sénégal, bien que limité à une version anglaise.
La taxonomie utilisée dans ce guide a évolué suite à la publication de nombreux travaux scientifiques, et il n’est pas rare que lorsqu’on parcourt un compte-rendu de voyage récent ou qu’on veuille saisir des données sur une base de données participative comme observado, ebird ou autre on tombe sur des espèces aux noms inconnus ou différents de ceux qu’on a l’habitude d’utiliser. La taxonomie, qui est la science s’attachant à nommer les organismes vivants, est comme son sujet d’étude : vivante. Elle évolue au gré des avancées scientifiques et technologiques, et permet de cerner les liens et différences entre espèces. Les noms donnés aux espèces peuvent donc évoluer, au grand dam de nombre de naturalistes. Cet aspect est à considérer, notamment quand on consulte la littérature ancienne. Un exemple de changement de nom d’espèce générant des erreurs d’appellation dans les carnets de terrain et sur les bases de données en ligne est celui du Pic goertan. Dans le livre de Morel et Morel Les oiseaux de Sénégambie (1990), ainsi que dans le vieux Serle & Morel (1993) – pendant longtemps l’unique guide de terrain pour l’Afrique de l’Ouest – le Pic goertan est nommé Pic gris, qui réfère aujourd’hui à une espèce différente, bien plus rare et présente au Sénégal uniquement dans le nord du pays, anciennement nommée Petit Pic gris.
Les concepts de délimitation d’espèces se font et se défont au cours du temps, et à l’heure actuelle les recherches ne permettent pas encore de lever le voile sur les liens taxonomiques au sein de certains groupes, comme c’est le cas chez la Pie-grièche « grise » que l’on observe au Sénégal, tantôt rattachée à la Pie-grièche méridionale et tantôt rattachée à la Pie-grièche grise. Parfois appellée “Pie-grieche grise du désert”, ce groupe comprendrait alors au moins trois taxons présents dans le pays: elegans, leucopygos et algeriensis.
Dans cet article nous listons tous les changements de noms effectifs depuis la parution de la deuxième version du guide Birds of Western Africa, et l’article sera mis à jour à chaque évolution taxonomique. La liste d’espèces proposée par l’International Ornithological Committee (IOC) sera prise comme référence principale ; c’est aussi celle que nous avons suivi pour établir la liste des oiseaux du Sénégal. Nous ne tenons pas compte dans cet article des évolutions taxonomiques n’amenant pas à un changement du nom d’espèce, tels que le changement d’orthographe des noms scientifiques ou les changements dans les rangs taxonomiques supérieurs au rang d’espèce (changement de famille).
Il faut savoir que la plupart des noms nouveaux ne sont pas issus de la découverte de nouvelles espèces, mais de la réévaluation du statut taxonomique d’espèces ou de groupes d’espèces grâce à l’utilisation d’outils et de techniques d’analyse génétique récentes. Le résultat de ces études est le plus souvent un split, qui est la reconnaissance de différentes espèces à partir de taxons avant considérées comme appartenant à une seule espèce. Sur la base de différences génétiques, morphologiques, accoustiques et/ou d’aire de répartition on aboutit alors à la description de nouvelles espèces. D’autres ajouts taxonomiques proviennent de l’étude d’espèces cryptiques, comme chez les drongos dernièrement. Des analyses génétiques ont permis de reconnaître un ensemble d’espèces différentes chez des espèces à large répartition montrant des variations morphologiques mineures d’une région à l’autre.
Si tout le monde s’accorde pour dire que le nombre actuel d’espèces reconnues en tant que telles est sous-estimé, certains chercheurs pensent même qu’il y aurait en réalité plus de 18’000 espèces distinctes, soit près du double du nombre actuellement établi. Des travaux récents (Fuchs et al. 2018) ont par exemple révélé que le Drongo brillant, espèce couramment observée dans les savanes ouvertes africaines, comprend un minimum de cinq espèces, et que le Drongo de Ludwig présent dans nos contrées est en fait une espèce bien distincte auparavant passée inaperçue.
Les résultats de tels travaux scientifiques ne sont pas toujours reconnus par toutes les instances nationales et internationales en charge de la taxonomie et de la nomenclature, et certaines instances reconnaissent un plus grand nombre d’espèces que d’autres. Afin de se maintenir au courant des avancées récentes en termes de taxonomie, il est possible de consulter le site web de l’IOC qui résume biannuellement les résultats des travaux scientifiques dédiés.
Voici donc la liste des principaux changements taxonomiques à prendre en compte depuis la publication du Birds of Senegal and the Gambia (2012) :
Puffin de Macaronésie (Puffinus baroli) ⇒ splitté en deux espèces présentes au Sénégal : Puffin de Macaronésie – Barolo Shearwater (Puffinus baroli) et Puffin de Boyd – Boyd’s Shearwater (Puffinus boydi). Il n’y a pas si longtemps que cela, ces taxons étaient considérés comme faisant partie du “Petit Puffin” (P. assimilis).
Puffin cendré (Calonectris diomedea) ⇒ splitté en deux espèces présentes dans les eaux côtières du Sénégal : Puffin de Scopoli – Scopoli’s Shearwater (Calonectris diomedea) et Puffin cendré – Scopoli’s Shearwater (Calonectris borealis). Auparavant, même le Puffin du Cap-Vert faisait partie de C. diomedea. Nous avions résumé les principaux critères d’identification de ces trois puffins dans cet article.
Grand Cormoran (Phalacrocorax carbo ssp lucidus) ⇒ Cormoran à poitrine blanche – White-breasted Cormorant (Phalacrocorax lucidus) ; à noter que le Grand Cormoran (Phalacrocorax carbo) est également présent sur la liste Sénégal. Le rattachement de la sous-espèce maroccanus du nord-ouest de l’Afrique à l’une ou l’autre de ces deux espèces reste sujet à discussion.
Milan parasite (Milvus migrans ssp parasitus) ⇒ Milan d’Afrique – Yellow-billed Kite (Milvus aegyptius parasitus), appelé “Milan noir d’Egypte” sur observado.org ; le Milan noir (M. migrans) est présent en tant qu’hivernant. Ce split n’a pas été retenu par le HBW, contrairement à la plupart des autres références.
Autour tachiro (Accipiter tachiro) ⇒ Autour de Toussenel – Red-chested Goshawk (Accipiter toussenelii) ; en Afrique de l’Ouest c’est la ssp. macroscelides qui est présente.
Talève sultane (Porphyrio porphyrio) ⇒ Talève d’Afrique – African Swamphen (Porphyrio madagascariensis)
Calao à bec rouge (Tockus erythrorhynchus) ⇒ Calao occidental (ou Calao de Kemp) – Western Red-billed Hornbill (Tockus kempi)
Hirondelle rousseline: la sous-espece domicella élevée au rang d’espèce devient l’Hirondelle ouest-africaine – West African Swallow (Cecropis domicella), résidente dans le sud et l’ouest du pays. L’Hirondelle rousseline (C. daurica) est donc également visible au Sénégal en tant qu’hivernant et migrateur venu des régions méditerranéennes.
Traquet de Seebohm – Seebohm’s Wheatear/Black-throated Wheatear (Oenanthe seebohmi) : Traité comme espèce par HBW et d’autres auteurs mais pas (encore) par IOC, pour qui c’est encore une sous-espèce du Traquet motteux ; voir notre récent article traitant de l’identification puis du statut de ce taxon.
Traquet à ventre roux (Thamnolaea cinnamomeiventris) ⇒ Traquet couronné – White-crowned Cliff Chat (Thamnolaea coronata) ; ce traquet inféodé aux milieux rupestres du sud-est du Sénégal hérite d’un nom on ne peut moins adapté à son plumage, sa tête étant uniformément noire.
Hypolaïs obscure – Western Olivaceous [= Isabeline] Warbler (Iduna opaca) élevée au rang d’espèce et séparée de l’Hypolaïs pâle – Eastern Olivaceous Warbler (Iduna pallida) ; si la première est très commune au Sénégal, la ssp. reiseri de l’Hypolaïs pâle est un visiteur bien plus rare et encore assez méconnu.
Fauvettes « passerinettes » splittées en 3 espèces, dont 2 sont sur la liste du Sénégal : Fauvette passerinette – Western Subalpine Warbler (Sylvia inornata) et Fauvette de Moltoni – Moltoni’s Warbler (Sylvia subalpina). Nous avions résumé les connaissances sur l’aire d’hivernage de cette dernière dans un article paru dans la revue Malimbus en 2017.
Cisticole roussâtre (Cisticola galactotes) ⇒ Cisticole du Nil – Winding Cisticola (Cisticola marginatus)
Camaroptère à tête grise (Camaroptera brachyura) ⇒ Camaroptère à dos gris – Grey-backed Camaroptera (Camaroptera brevicaudata)
Gobemouche méditerranéen – Mediterranean Flycatcher (Muscicapa tyrrhenica) splitté du Gobemouche gris (M. striata) et également présent au Sénégal. Les deux taxons sont très délicats à identifier sur le terrain, et ce split n’a pas été adopté par toutes les instances.
Gobemouche de l’Atlas – Atlas Pied Flycatcher (Ficedula speculigera) élevé au rang d’espèce; le Gobemouche noir est bien sur également présent en hiver.
Pie-grieche méridionale ssp elegans et leucopygos – Southern Grey Shrike (Lanius meridionalis) ⇒ Pie-grièche grise – Great Grey Shrike (Lanius excubitor), attention taxonomie très fluctuante et potentiellement amenée à évoluer : il paraît assez logique que les Pie-grièches “grises” d’Afrique du nord et du Sahel soient élevées au rang d’espèce, la Pie-grièche du désert.
Pie-grièche isabelle (Lanius isabellinus) ⇒ splittée en 2 espèces, Pie-grièche du Turkestan – Red-tailed Shrike (Lanius phoenicuroides) et Pie-grièche isabelle – Isabelline Shrike (Lanius isabellinus), celle présente au Sénégal étant vraisemblablement la première.
Drongo brillant (Dicrurus adsimilis) ⇒ Dicrurus divaricatus (Glossy-backed Drongo, nom français pas encore connu; on pourrait logiquement retenir le nom d’origine donc Drongo brillant).
Drongo de Ludwig (Dicrurus ludwigii) ⇒ Drongo occidental – Western Square-tailed Drongo (Dicrurus occidentalis) – voir notre billet au sujet de ce taxon.
Bruant cannelle (Emberiza tahapisi) ⇒ Bruant d’Alexander – Gosling’s Bunting, parfois aussi appellé Grey-throated Bunting (Emberiza goslingi).
Plusieurs splits sont attendus dans le futur, notamment la séparation des populations africaines et américaines de la Sterne royale, le changement de statut de la sous-espèce africaine de l’Agrobate roux (Agrobate mineur, qui deviendrait alors Cercotrichas minor), la séparation entre le Tisserin à cou noir et le Tisserin pirate (Ploceus brachypterus), l’Amarante masqué splitté en trois taxons distincts (dans la sous-région, elle devient alors l’Amarante vineux, Lagnosticta vinacea). Et bien d’autres encore !
Affaire à suivre!
Simon & Bram