During our most recent excursions, we obviously looked out for those colourful Afro-tropical migrants that typically arrive in June-July, moving north with the rains – think cuckoos, rollers, kingfishers, etc. We saw some of course, especially at Wassadou but even in the bone-dry landscapes of Gossas and Diourbel, where we had migrants such as Diederik Cuckoo and Grey Hornbills.
Less expected were a number of breeders from the Western Palearctic that are now supposed to be in full breeding mode, so I thought it would be interesting to review these here. Of course, numerous “WP” species that winter in Senegal can be seen here year-round, but these are mostly waterbirds such as Eurasian Spoonbill, Black-tailed Godwit, Audouin’s Gull and other waders, gulls and terns. Many young birds of these species will actually remain in West Africa during their first summer, and from the end of June it’s quite normal to see early returnees, particularly for waders that failed their breeding season and left Europe early.
A Western Marsh Harrier (Busard des roseaux), probably a young female, flew over the flock of Greater Flamingos and other waterbirds that we’d just been counting at Lac Mbeubeusse, one of the niayes wetlands on the Cap-Vert peninsula, then landed in a reedbed. Some summer observations are known from both Senegal (“a few birds summer”, Morel & Morel) and Mauritania (June-August; Isenmann et al.), and Barlow & Wacher mention that occasional non-breeders are seen “during the rains” (a rather vague way to refer to summer, which doesn’t really tell us whether the records were actually during summer or whether they refer to regular migrants in September & October!).
Also here on the same day (23.6) was at least one immature Purple Heron (Héron pourpré) which may be either an oversummering bird of European origin, or a wandering African bird – I’m yet to figure out whether the species breeds anywhere nearby, though it’s clear that in potential breeding areas such as Technopole the species is absent during ~March to early August (further south, I have records from May-June, in Kolda and Toubacouta).
Still at Mbeubeusse – a decent birding site I’d never visited before despite being not far from Dakar! Never too late… – we also saw a winter-plumaged Knot (Bécasseau maubèche), feeding together with a group of Grey Plovers and a handful of Greenshanks and Redshanks. (Pluvier argenté, Chevaliers aboyeur et gambette). While the latter three species are more or less to be expected at this time in Senegal, the summer record of Calidris canutus may be noteworthy.
Two subadult Yellow-legged Gulls (prob. 3rd c.y.; Goéland leucophée) were at Lac Rose on 23.6, resting together with a group of some 500 Lesser Black-backed and 200 Audouin’s Gulls (Goélands bruns et d’Audouin), several of which were ringed including a Portuguese bird that I’d already seen back in April at Technopole. Also in the group were two or three Kelp Gulls (Goéland dominicain). Yellow-legged Gull is rather scarce here at any time of the year so it was a nice surprise to see these; apparently the species has been “recorded in all seasons” in Senegambia (Barlow & Wacher). Both birds seemed to be typical nominate birds (i.e. from southern Europe) rather than atlantis birds from the Macaronesian islands.
A week earlier at Wassadou and along the road from Tambacounda to the Niokolo-Koba, we noted a good presence of Common & Pallid Swifts (Martinets noir et pâle), which appears to be not unusual at this time of the year since non-breeding birds are said to move north with the rains from their “wintering” grounds over the forest zone of West Africa. There are however few June records (e.g. Barlow & Wacher give a presence of Pallid Swift from July-September and November-January). Even more exciting was the presence of several Mottled Swifts (Martinet marbré) at Wassadou, the first June record of a “difficult” bird in the region – there appear to be less than 10 records for Senegal in total, all of which are from the Niokolo-Koba area. The one below was seen by my Swiss friends in the PNNK earlier this year.
Perhaps more surprisingly than the preceding species, two European Bee-eaters (Guêpier d’Europe) were feeding and flying around pretty much all afternoon on 23.6 in Almadies, Ngor, regularly calling in the process and as such giving away their presence above and near my house. I’d never seen the species before in Dakar (though I have seen them not far, along the Petite Côte in autumn), so this was a highly unexpected record. Paul Isenmann and colleagues mention that the species is present in Mauritania from July/August to October, and March to May/June, but I didn’t find any references to summer records in Senegal or Gambia. Probably just a coincidence, but earlier the same day we saw our first Blue-cheeked Bee-eaters in the Dakar region, at Lac Rose (Guêpier de Perse). Perhaps these were birds en route to their breeding grounds in northern Senegal?
A single House Martin (Hirondelle de fenêtre) at Wassadou on 15 & 16.6 was also remarkable: a very late migrant, an oversummering bird, or a wanderer that decided not to bother going all the way to Europe? The species has been recorded Oct. – June and I’ve seen birds as late as 28/5 at Technopole, but it’s clear that there are very few records from late June and July.
A Melodious Warbler (Hypolaïs polyglotte) photographed by Gabriel in the Niokolo-Koba park, at campement du Lion, on 17.6 is another rare mid-summer record of a species that typically arrives from mid-August and depart by May at the latest. Gabriel recently saw the species in the Boundou community nature reserve as well, so it seems that quite a few are staying around during summer. More generally, one can only wonder how many of these Palearctic passerines are here at the moment. Putting things in perspective, the observations in this post are all by just 3 active resident birders in the country…
A few kilometres further north, Miguel and I observed a Western Olivaceous Warbler (Hypolaïs obscure) at Wassadou, feeding in bushes on the edge of the Gambia river, on 16.6. This is of course a common to very common winter visitor throughout the country, and there are records from all month, so maybe not as surprising as the previous species. Now often called Isabelline Warbler, it is also known to be summering at Nouakchott (June-July) with no noticeable break between pre- and postnuptial passages (spring: March – May/early June, autumn: July-October; Isenmann et al. 2010).
A couple of days later near Diourbel, we had a Woodchat Shrike (Pie-grièche à tête rousse), apparently a first-summer male: the forehead is extensively black and mantle seems mostly jet-black (both features indicative of males), while the moult limit between the adult-type dark wing feathers and juvenile brownish unmoulted primary coverts and flight feathers are typical of 2nd calendar year birds (more on ageing & sexing the species here, from Blasco-Zumeta & Heinze’s excellent series on the topic). The presence of this species in Senegal is fairly similar to Western Olivaceous Warbler. An adult Great Spotted Cuckoo (Coucou-geai) earlier that day near Gossas was assumed to be an African rather than a northern migrant, though we can’t be sure of course; the date is consistent with the arrival of this cuckoo on its Sahelian breeding grounds (a couple of weeks later I had another adult, actively calling, though a bit further east: along the Niger river near Niamey).
Voilà for now; for me it’s time to migrate north for a couple of weeks (though no breeding for me this summer); I’ll be back towards the end of the month. And maybe find some time to finish a few blog posts that have been dormant in my draft folder for a while now… Thanks for reading!
Following on our April summary, here’s a brief update on results from last month’s short but regular seawatch sessions from Ngor, as usual all from the Club Calao terrace. Managed a total of 10 sessions between May 10th and May 26th, with more good stuff to report on, including a lifer!
Again, no pictures other than a few old ones that I’m recycling here… and yet again a pretty dull species list.
Wilson’s Storm-Petrel (Océanite de Wilson): unidentified storm-petrels were regularly seen in small numbers, and most likely referred to this species.
Cape Verde Shearwater (Puffin du Cap-Vert) were seen in good numbers on most days, feeding off Ngor or flying NE, with a max. of at least 540 birds in one hour on 26th. Not as many as last year when the maximum counted on a single day exceeded 5,000 birds (!), but the pattern of appearance and behaviour of birds is very much in line with the previous season.
Cory’s / Scopoli’s Shearwater (Puffin cendré / de Scopoli): at least three on 26th when there was a remarkable diversity of shearwaters, with five species noted. Probably also a few on 11th, 14th and 15th but too far or seen too briefly to positively identify.
Two to five Great Shearwater (Puffin majeur) seen flying NE amidst the other shearwaters on 26th – remarkably similar to last year’s record of two birds on May 25th, noted as “apparently migrating north” and thought to be the first May record – see the short paper we published in the latest volume of Malimbus on a “wreckage” of Great Shearwater in the the occurrence in Senegal & Gambia (Barlow et al. 2018), PDF available here on my ResearchGate page.
Sooty Shearwater (Puffin fuligineux): a few seen on 18th, 21st and 26th, with at least 12 birds on the latter date: these records suggest that this Southern Hemisphere breeder is slightly more numerous later in spring.
Boyd’s / Barolo Shearwater (Puffin de Boyd / Macaronésie): one on 21st seen at fairly close range was identified as Barolo Shearwater – for once it was close enough and I was able to follow it over quite a distance. Probably a bird en route to its breeding grounds. Another one, also flying north-east, was either baroli or boydi. The taxonomic situation of these small black and white shearwaters is complex and seems to be constantly changing. with BirdLife and HBW now treating both taxa as subspecies of Audubon’s Shearwater (Puffinus lherminieri). Either way, these are apparently quite rare spring records, though Dupuy (1984) lists what was then known as “Little Shearwater” as an uncommon offshore “summer” visitor. Boyd’s Shearwater breeds exclusively on the Cape Verde islands (only about 5,000 pairs!), while Barolo’s breeds further north on the Macaronesian islands where it is known from Madeira, the Azores, the Selvagems, and the Canary Islands, with a total breeding population of the same order of magnitude.
Northern Gannet (Fou de Bassan): seen in small numbers on most days; all but one were immature birds (and one on 15th may actually have been a Cape Gannet, but I couldn’t rule out a 4th year Northern Gannet as I didn’t see the underwing pattern…).
Red-footed Booby (Fou à pieds rouges): a species I’d never seen before but somehow expected to show up one day at Ngor, two were seen feeding in the surf just beyond the Ngor islet on 17th, nicely showing their pink (not red!) feet, bluish bill and uniform brown plumage. One was seen again the following day and what I assume are the same two birds (both dark morph adults or near-adults) on 22nd, when they appeared to take off from the islet where they may have spent the night. Third record for Senegal! More on this species, which will likely show up more frequently in coming years, in this recent post.
Brown Booby (Fou brun): just one record so far, of an immature (2nd c.y.) on 14th. Looks like the Iles de la Madeleine birds – if they are indeed still present – don’t wander around the peninsula too much.
A few Great While Pelicans were regularly seen, flying about or resting out at sea (and once on the islet), and on 26th a Pink-backed Pelican made an appearance (Pélicans blancs et gris).
Other than an Oystercatcher on 20th and three Whimbrels on 11th (and a few Common Sandpipers), no more waders were seen during May (Huîtrier pie, Courlis corlieu, Chevalier guignette).
Long-tailed Skua (Labbe à longue queue): following several records in the latter half of April, at least three were identified on 11th, one on 18th, and one on 26th – confirming that spring migration of this species occurs up to the end of May off Senegal. Pomarine and Arctic Skuas were much scarcer than in April, with just three records for the former and five for the latter species.
Audouin’s Gull (Goéland d’Audouin): up to three birds seen in any one session, though no notable active migrants as was the case in April; all were immature birds.
Sabine’s Gull (Mouette de Sabine) were recorded up to May 22nd, with four records of 1-9 actively migrating birds. Other gull species included 10 Grey-headed Gulls flying NE on 20th, and three Slender-billed Gulls on 22nd. A single Lesser Black-backed Gull was seen on 22nd, when a probable Kelp Gull was also present.
Single Bridled Tern (Sterne bridée) were seen feeding and flying around quite close to shore on 11th and 15th, bringing the total to three birds so far this season.
Lesser Crested Tern (Sterne voyageuse): seen twice (17th & 20th), unlike African Royal Tern (Sterne royale) which remained present in decent numbers throughout. Caspian Tern (Sterne caspienne) was seen just once, on 22nd.
Roseate Tern (Sterne de Dougall): following a decent passage in April, just one seen on 17th, though others may have passed through further offshore amidst Common and Arctic Terns (Sternes pierragarin et arctique). These two species were seen almost daily, but again in much smaller numbers than in April.
Three Whiskered Terns (Guifette moustac) flew past on 11th, followed by two White-winged Terns (Guifette leucoptère) on 21st. Black Terns (Guifette noire) were less numerous than in April, except on May 11th when about 300 birds were counted.
Let’s see what June brings! Assuming that I manage to make it out to the Calao…
A new observation of a Franklin’s Gull at Technopole, on May 20th, prompted me to have a closer look at the records of this American species in Senegal and more generally across West Africa. I’ve been compiling records of Nearctic vagrants for some time now, which I may use one day to write up a formal publication on the topic – the list currently includes 83 records of 18 different species and some patterns are starting to emerge.
No less than 21 of these records are of Franklin’s Gulls, though these correspond to at least 36 different observations (one record can refer to a bird seen over several dates). As such, this is by far the most frequent American vagrant seen in Senegal. It’s actually been annual at Technopole since 2011, year that saw the arrival of three different birds. In the following three years, at least five different birds were regularly seen, to the extent that Franklin’s Gull became an expected feature at Technopole during that period (I was lucky to see one of these birds in July 2012, during a visit with Paul). It’s been quite difficult to determine how many records there actually are, as it’s not always clear when multiple records relate to a single bird, and whether the recent spring sightings at Technopole (2015 – 2017) may also be all of just one returning adult.
Here’s the most recent bird:
This year’s bird is clearly not a returning adult, as it appears to be a second calendar year (“first summer”) bird. Ageing Franklin’s Gull is not always straightforward – see K. M. Olsen’s comment in this short post by Paul – but I think this bird can be fairly safely identified as a second year bird, based on the head pattern (adults such as last year’s should have a completely black hood) combined with a small amount of white in the primary tips – and note active moult of primaries.
This is what we have in terms of records so far – corrections and additions welcome!
- 29.5.83 Delta du Saloum, Fatick, paired with Grey-headed Gull, sitting on nest (Erard et al. 1984)
- 17.1.86 Ile de Gorée, Dakar, first winter (F. Baillon) (Baillon & Dubois 1992)
- 24.4.86 Delta du Saloum, Fatick, among Grey-headed Gulls (C. Devisse) (Baillon & Dubois 1992)
- 3.12.88 Plage de Hann, Dakar, adult (J. J. Blanchon, P. J. Dubois, J. P. Pillion) (Baillon & Dubois 1992)
- 18.2.91 Plage de Hann, Dakar, first winter (P. J. Dubois, P. Le Maréchal et al.) (Baillon & Dubois 1992)
- 28.2.07 Saint-Louis, adult (J. Piette; H. Dufourny; ABC Recent Reports Vol. 14(2) & 15(1))
- Oct. 2008 Ngor, Dakar (French seawatch team)
- 26.1.11 Bao Bolon, Kaolack, 2nd year (R. Ottvall et al. – trip report here)
- 24.7 – 1.8.11 Technopole, two 2nd year (P. Robinson)
- 5.8.11 Technopole, 2nd year, different from previous two birds (P. Robinson)
- 29.10.11 Yoff, Dakar (P. Robinson)
- 11.2.12 Technopole (J.-F. Blanc, S. Cavaillès)
- 3.5 – 18.8.12 Technopole, up to three seen min. nine times (P. Robinson, S. Cavaillès, BP)
- 18.5.12 Almadies, Ngor, near lighthouse Pointe des Almadies, seen from boat (P. Robinson)
- 16.4 – 4.8.13 Technopole, up to four seen min. eight times (P. Robinson et al.), also one on 18.8 at lac Mbeubeusse (P. Robinson, G. Citegetse et al.)
- 6-16.3.14 Technopole, adult (P. Robinson; J.-F. Blanc)
- 15-20.3.15 Technopole, adult (BP; J.-F. Blanc)
- 3.5.15 Technopole, adult (BP) – possibly the same as in March, or a different bird (and treated as such in this list).
- 13.7.16 Technopole, adult (W. Hagemeijer, M. van Leeuwen; photo on observado.org)
- 14.5.17 Technopole, adult (BP)
- 20.5, 10.6 & 7.7.18 Technopole, 2nd year (BP, M. Lecoq, G. Caucanas)
There’s obviously a clear increase in the number of records in the last eight years, even since 2007 after which this neat gull was not seen during two years only. The arrival of up to five different immature birds in 2011-2014 is noteworthy and as far as we know this was unprecedented in Africa. With the exception of this year’s bird, it’s quite possible that the single adults seen at Technopole since 2014 all refer to one or more of these original five, spending the winter further south and moving back north through Senegal in spring.
The near-absence of records prior to 2011 doesn’t mean much, since observer coverage was much lower then, so it’s hard to say anything much about longer term trends: the increase in records is probably in a large part related to increased observer pressure, particularly in Dakar where the majority of records are from. This also makes more sense, rather than that it reflects a real increase in records, considering that Franklin’s Gull is a species that’s said to be declining, particularly in the U.S.
Below is an attempt to plot the number of observations (not records!) and the number of birds involved, based on available data up to early June.
Here’s one of the 2011 birds from Technopole, thought to be second year:
This one is from barely a week later, and is thought to be an adult moulting into winter plumage:
And here’s the adult in full breeding plumage from May 2012 at sea off Almadies. Besides the all-dark hood, note the greater amount of white in the wing tips compared to immature birds:
Trying to unravel any seasonal patterns is tricky with so few records, though in recent years it’s clear that most birds show up between March and August, with the most recent observations all from March, May and July. There are only a couple of October records, none from September and November, and at least since 2013 there’s no evidence of wintering birds (if there were any on the Dakar peninsula, we’d probably see them at least from time to time at Technopole!). On the chart below, I’ve included birds that were seen over multiple months in each of the months’ totals, hence the sum of records exceeding 21.
The breeding record from the Saloum delta is of course intriguing, and it’s not excluded that more attempts have occurred again since the 1983 record.
Records from elsewhere in West Africa are much rarer than in Senegal: in Mauritania, one was seen on 27.1.06, followed by a second record on 17.4.16, both at Banc d’Arguin (Bull. African Bird Club 23: 238), then a third on 23.4.17 in Nouakchott (see Robert Tovey’s account on the find here). In The Gambia, Franklin’s Gull was seen in 1984, on 17.1.02, and again on 8-9.2 until 15.3.05 at least; all records are from Banjul. The first for Ghana was an adult on 8.5.11 on the Sakumono lagoon on the outskirts of Accra.
Nine records are known from Morocco, the most recent one being a first-winter bird on 12.2.16 at Oued Souss (Agadir) – so clearly not one of the Senegal birds as these were all adults by then.
Elsewhere in Sub-Saharan Africa, there are several records from South Africa, at least two from Mozambique, one from Congo-Brazzaville (one on 14.11.15 at the Kouilou-Niari River), at least one from Burundi, Uganda, Malawi, Namibia and Zambia, and the species is also listed as a vagrant to Ascension island and Tristan da Cunha. And the first for the Seychelles was seen on 7.5.17. They really do wander about!!
Franklin’s Gull – now known as Leucophaeus pipixcan – is a widespread colonial breeder on the prairies of northern North America, wintering mainly in coastal regions on the Pacific coast of South America (Colombia – Chile; range map xeno-canto). It’s a regular vagrant to Europe, and stragglers have been recorded as far as Kazakhstan, Australia and New Zealand, even Antarctica.
A few references
Baillon, F. & P.J. Dubois, 1992. Nearctic gull species in Senegal and The Gambia. Dutch Birding 14:49-503
Érard, C, Guillou, J.-J. & Mayaud, N., 1984. Sur l’identité spécifique de certains laridés nicheurs au Sénégal. Alauda 52:184-188
Quick update on this past month’s seawatch sessions from Ngor, as there have been a few good species lately. As usual, most of these are from short sessions at the Calao, with a few from Pointe des Almadies and from a mini-pelagic on April 22nd. Here’s a rather dull species list, but given that still fairy little is known about the phenology of spring seabird migration off Dakar, I thought it would be worthwhile reviewing them here. I don’t really have any recent pictures to illustrate these records, except for a really poor header picture of a Sabine’s Gull actively migrating past the Pointe, and a few older pics that I’m recycling in this blog post.
So here we go:
Cape Verde Shearwater (Puffin du Cap-Vert): the first few birds were seen on 3.3 (min. 2), then ca. 20 on 16-17.3, and a regular presence was noted throughout April when seen during most sessions from 4th, typically 50-100 birds feeding offshore, at most ca. 490 birds on 27th (but just a handful the next day and none seen on 29th!).
Scopoli’s Shearwater (Puffin de Scopoli): at least one during our boat trip on 22.4, with Cory’s or Scopoli’s noted from Ngor on 28th (as well as on March 3rd & 11th).
Sooty Shearwater (Puffin fuligineux): first seen on 16.3, then again singles on 31/3 and 7/4, and at least three birds on 20th. Not much… and note that we didn’t see a single bird during our boat trip.
European Storm-Petrel (Océanite tempête): after a good presence during the first half of February, the species was seen again on 22.4 from the boat, with a minimum of two birds.
Wilson’s Storm-Petrel (Océanite de Wilson): at least six were seen on 22.4, again during our boat trip. Unidentified storm-petrels migrating past the Calao on 7th (min. 8), 11th (3), 20th (3) and 29th (1) were likely this species, though others can’t be ruled out – when seen from land, these birds can be incredibly difficult to identify due to either the distance or the very brief sightings as they always fly low over the water surface and are typically seen only for a second or two before they disappear again in between waves.
Northern Gannet (Fou de Bassan): at most ca. 175 on 31.3, with numbers gradually decreasing throughout April. Curiously, no marked NE-ward passage was noted.
Grey (Red) Phalarope (Phalarope à bec large): four migrating on 29th was a good spring record! Other than these, the only waders seen during this period were a few groups of Whimbrel (Courlis corlieu).
Long-tailed Skua (Labbe à longue queue) single adults passing through on 20, 21 & 25.4, two on 26th, and an immature flew past on 29th. Pomarine and Arctic Skuas were seen in small numbers on most days, many of which were flying NE (though rarely more than five in any one session).
Lesser Black-backed Gull (Goéland brun): usually present in small numbers, either feeding in the surf or migrating past Ngor. There was obviously a peak around mid-March, with 107 passing through in just 40 minutes on 16.3, and 52 in half an hour the next day.
Audouin’s Gull (Goéland d’Audouin): typically between one and five birds seen on any one session, but on 16.3 there were 27 (incl. three adults) migrating past in 40 minutes and 14 the following day (in 30 minutes) – thus coinciding with the peak of the previous species.
Sabine’s Gull (Mouette de Sabine): after the first five on 4.4, becomes increasingly frequent towards the end of the month, with a max. of ca. 40 during our 22.4 boat trip, and 31 on 27th in just one hour. Actual numbers must be quite a bit higher as this species mostly passes through far out, typically in small groups. Sometimes a few birds would migrate closer to shore, and occasionally some would be feeding or resting just in front of the Calao. Other gull species included a surprising flock of 31 Grey-headed Gulls flying NE on 27th, and six Slender-billeds at Pointe des Almadies the following day.
Bridled Tern (Sterne bridée): one passing to the NE at fairly short range on 26.4 was a very nice surprise, as I’d only seen the species once before here (and more generally, away from the Iles de la Madeleine breeding grounds). It also appears to be an early date for the species, as it is typically seen in May-July. My only previous Ngor record was of three birds flying SW on 10 June ’16. Sauvage & Rodwell give the range of 27/4 – 9/7 for PNIM, and A. R. Dupuy recorded the species no less than eleven times from Pointe des Almadies from 26 May to 14 July ’92.
Lesser Crested Tern (Sterne voyageuse): seen in small numbers throughout the month, with a good max. of at least 178 birds passing through on 9th, in just 65 minutes. African Royal Tern (Sterne royale) was seen on most days, typically in small numbers. Much less frequent were Caspian Tern (Sterne caspienne; singles on 31.3 and 28.4) and Little Tern (Sterne naine; one on 6.4, and a group of 16 migrating on 29th).
Roseate Tern (Sterne de Dougall): first seen on 31.3, then regular until the middle of the month with a max. of no less than 56 on 9th in just over an hour. Also singles on 26th and 28th. Most birds were actively migrating, with a few feeding locally with the mixed tern flock.
Arctic Tern (Sterne arctique): the first four birds were seen on 16.3, becoming regular from the end of March and seen on most sessions in April, max. ca. 70 on 24th though numbers probably higher as 1) species difficult to count, and many common/Arctic terns noted.
White-winged Tern (Guifette leucoptère): one flew past on 16.3, and a fine adult in summer plumage was feeding among the numerous Black Terns on 28.4 (Guifette noire). The latter species is seen pretty much during every session, with a maximum towards the end of the month: probably more well over 1,200 birds on 28th. An adult Whiskered Tern (Guifette moustac) was seen on 22nd, flying NE.
That’s about it for now.
On the raptors front, Osprey has been a regular sighting, as always during winter, until 31.3 at Ngor, after which one was seen on 13.4 at Mamelles and on 14.4 at PNIM. A few young birds may still hang around of course. The wintering pair of Peregrines was last seen on 20.4 roosting on the Diarama hotel, and two birds were seen roosting in the Mamelles cliff on 22.4 – pretty intriguing!
Sortie dominicale de routine au Technopole avant-hier 29/4, avec comme presque toujours quelques observations intéressantes à la clé.
A commencer par ces trois Goélands dominicains (Kelp Gull), espèce rarement observée au Technopole et à Dakar de manière générale : en scannant un groupe de laridés essentiellement composé de Goélands d’Audouin (quelques 85 inds. en tout, un bel effectif pour le site; Audouin’s Gull), un oiseau costaud sort du lot et lorsque j’arrive à voir son bec massif, je peux confirmer qu’il s’agit bien de Larus dominicanus, pas de doute possible cette fois. Un individu adulte ou presque, de taille nettement supérieure aux quelques Goélands bruns (Lesser Black-backed Gull) dans le même groupe, au bec énorme, un manteau bien sombre, et des pattes grises très claires tirant vers le vert. L’iris sombre est conforme à la ssp. vetula (Goéland du Cap, Cape Gull). A côté de lui se tiennent deux immatures avec la même structure et des pattes de la même couleur que l’adulte, soit trois Dominicains en tout. Les deux jeunes ont un âge similaire, ayant un plumage de type “2e cycle”, donc dans ce cas précis ce seraient des oiseaux nés en 2016. A part la taille et la forme du bec, la couleur des pattes est diagnostique et permet de rapidement repérer l’espèce au milieu de groupes de Goélands bruns, qui ont des pattes jaunes (adultes et subadultes) ou roses (immatures). Les trois oiseaux sont visibles sur la photo ci-dessous.
Pour plus d’infos sur l’identification des Goélands dominicains, voir notamment cet article de Jiguet et al. paru dans Birding World (2002), et aussi ici pour ce qui est des oiseaux de premier cycle.
Clive Barlow et Tim Dodman se sont penchés sur la population ouest-africaine, dont le petit noyau se trouve dans le delta du Saloum où l’espèce niche de manière régulière depuis 1980 au moins, lorsqu’un couple présumé mixte G. dominicain x G. brun fut trouvé sur l’Ile aux Oiseaux. Par la suite, des nidifications par des couples purs sont prouvées dès 1983 par Erard et al. Quelques individus fréquentent régulièrement la Gambie et la Mauritanie, et s’y reproduisent parfois, peut-etre aussi en Guinée-Bissau? Et avec l’intérêt grandissant que portent les ornithos européens au Sahara occidental – ou Sahara atlantique marocain, selon quel point de vue politique on adopte! – l’espèce est vue plus ou moins régulièrement en très petits effectifs plus au nord sur le continent, et il y a même quelques observations récentes au Portugal et en France. Clive et Tim émettent l’hypothèse que notre petite population isolée soit établie par quelques oiseaux égarés depuis l’Afrique australe (Afrique du Sud / Namibie), et que cette population soit maintenant autonome sans qu’il n’y ait de mouvements réguliers entres les populations australes et celle d’Afrique de l’Ouest. Il y aurait ainsi entre 20 et 50 couples dans la région. Une étude génétique est en cours ou du moins est-elle prévue, sauf erreur.
En région dakaroise, ce goéland hautement côtier est assez régulièrement signalée par des observateurs de passage, mais je ne suis pas sûr que toutes les observations soient réellement fiables… D’après mes propres données de ces trois dernières années le Goéland dominicain est très peu fréquent. Cela dit, je ne suis pas un larophile et si je faisais plus attention à ce groupe difficile que sont les grands goélands, j’en verrais probablement plus souvent!
Ainsi, Niklas Holmström et collègues en signalent pas moins de 20 entre le 13 et le 27/10/03 devant Ngor, mais un seul entre le 3 et le 16/10/05. Une équipe danoise en compte même 57 en « en migration vers le sud » du 22 au 29/10/04 – vraiment étonnant vu que l’espèce n’est présente qu’en très faibles effectifs plus au nord, et qu’en plus ils ne signalent aucun Goéland brun alors que c’est l’espèce dominante à cette période. En 2010, on passe à des effectifs plus raisonnables me semble-t-il, avec trois individus entre le 30/9 et le 8/10 (R. Lebrun) et autant du 25 au 31/10/10 (P. Crouzier & co.). Plus récemment, un Goeland dominicain est rapporté le 24/2 de Ngor par un groupe de naturalistes belges.
Pour ma part, ma seule autre observation au Technopole datait du 6/8/17, d’un immature que j’avais identifié comme dominicain et dont je reprends une des photos floues ci-dessous (l’autre est là) – commentaires bienvenus! Puis avec Manuel en février dernier on a également soupçonné un dominicain, mais trop loin et pas de photos pour confirmer l’identité de l’oiseau. Idem les 11 et 30/8/17 lorsque des probables dominicains passent devant Ngor.
Autre observation intéressante, celle d’un probable Heron « pâle », la sous-espèce monicae du Héron cendré qui ne niche qu’au Banc d’Arguin et peut-être ailleurs sur les côtes en Mauritanie et que certains considèrent même comme une espèce à part entière (“Pallid” or “Mauritanian” Heron). L’aspect très clair était frappant, et malgré la distance on arrive à bien voir les petites stries noires, fines et courtes, sur le cou qui comme le reste des parties inferieures parait presque aussi blanc que la Grande Aigrette. Le manteau était d’un gris pâle à l’exception d’une tache plus sombre à « l’épaule ». Il y a juste le dessin de la tête qui peut sembler un peu top contrasté pour un monicae classique, mais en regardant de près les quelques photos d’oiseaux mauritaniens cela semble encore rentrer dans la normale pour cette sous-espèce. Pour compliquer la chose, il y aurait des oiseaux intermediaires, et peut-être que c’est donc aussi le cas pour notre oiseau du Technopole (visibement un adulte nuptial). Bien entendu je suis preneur d’autres avis!
Il doit s’agir d’un des ardéidés les plus rares au monde, la population totale ne comptant que quelques milliers d’individus, avec une aire de répartition très restreinte. Si c’est bien un mauritanien, alors il s’agirait de ma première observation d’un oiseau manifestement rare à Dakar. Ces derniers mois il y a eu au moins deux autres observations dans la région : un le 13/2 au parc de Hann (Gottlieb Dandliker, Cyril Schönbächler; photo ci-dessous) et un le 24/2 aux Iles de la Madeleine (M. Demeulemeester et al.). Monicae est plus fréquente en hiver dans les zones côtières du nord du pays, notamment autour de la Langue de Barbarie et Saint-Louis, mais même là le taxon reste d’observation plutôt aléatoire. Les observations d’Ornithondar permettent d’en savoir plus sur le taxon dans le Bas-Delta, et de comparer les photos avec l’oiseau du Technopole: articles bien instructifs ici et là.
Tout cela pour dire qu’en gros, aussi bien l’identification que le statut et la distribution au Sénégal restent encore à préciser! On trouvera quelques infos résumées sur la page dédiée au Héron cendré sur le site du groupe HeronConservation.
Troisième espèce inattendue, vue par chance alors que j’étais en train de quitter le site : six Bengalis zébrés (Zebra [Orange-breasted] Waxbill). Ce sympathique petits passereau avait été vu pour la première fois au Technopole en janvier-mars 2017, et depuis j’ai pu en voir également à Yène, plus précisément le 1er janvier dernier. On peut donc supposer que ce nicheur du Bas-Delta sénégalais et du Saloum soit un erratique plus ou moins régulier dans la région dakaroise.
Pour le reste, il y a de nouveau un petit groupe de Flamants roses (10 ind.), les premiers poussins d’Echasses blanches – juste trois pour le moment, déjà vus le 21/4 – et plusieurs adultes en train de couver; également un poussin de Vanneau éperonné; quelques Bécasseaux variables et surtout une bonne présence de Sanderlings (+150) et de Sternes caugeks notamment; une Hirondelle de rivage retardataire; et toujours quelques Spatules blanches et d’Afrique (Greater Flamingo, Black-winged Stilt, Spur-winged Lapwing, Dunlin, Sanderling, Sandwich Tern, Sand Martin, Eurasian & African Spoonbill). Sinon assez peu de limicoles, la plupart des chevaliers, pluviers, combattants et autres bécasseaux étant de retour en Europe maintenant: on attend déjà leur retour, d’ici deux mois à peine pour les avant-coureurs. Par contre, il y a toujours autant de Bihoreaux gris: une bonne trentaine (Black-crowned Night-Heron).
Le Souimanga cuivré est vu à chaque sortie en ce moment, et la semaine passée il y avait également un superbe mâle de Souimanga éclatant, photo ci-dessous (Copper & Splendid Sunbird).
Kordofan Lark (Mirafra cordofanica) is a poorly documented African lark species occurring in the Sahel. In West Africa it is known from Mauritania, Mali, Niger and Burkina Faso and its status in Senegal is considered to be that of a vagrant. A recent observation by a Belgian tour group led by Miguel Demeulemeester in March 2018 gives us a good opportunity to have a closer look at this species’ identification and its occurrence in Senegal.
Despite the quite broad range occupied by Kordofan Lark, which covers eight countries, it appears to be a highly localized resident. It is quite remarkable to note that there is not a single picture or video available on the Internet Bird Collection, nor are there any sound recordings on xeno-canto and other online sound libraries! It is probably the only bird species found in Senegal in that case. This is probably because the countries where the species is regular are not top birding destinations nowadays. A thorough internet search only takes you to a set of pictures taken in Niger by Tim Wacher, though it appears that these birds are actually Dunn’s Lark and not Kordofan as initially thought – see further down for a discussion of identification. The pictures taken by Jan Heip are therefore a very good contribution to the online presence of this scarce lark. As it turns out, they may well be the only pictures available online!
Kordofan Lark in Senegal
The first record of the species has been published by Morel & Roux (1962). Since this first observation a few more records have been added, which in most cases are not documented.
- Collected or observed 4 or 5 times in grassland close to Richard Toll, April to June 1960 (Gérard Morel)
- One close to Bakel, January 1983 (H. Schifter in Morel & Morel 1990)
- At least one in the Richard Toll area, during a visit from 30 December 1993 to 5 January 1994 which “produced single records of Golden Nightjar, Little Grey Woodpecker and Kordofan Bushlark […] (per TG).” (Recent Reports, African Bird Club)
- One record of a single bird NE of Louga (15°41´N, 16°7´W) on 30 July 2004, during North-South transects as part of a study on bird population densities along two precipitation gradients in Senegal and Niger (Petersen et al. 2007)
- 4 individuals, Ndiaël, 4 December 2004 (Richard Cruse in Recent Reports, African Bird Club Bulletin)
- 1 individual, southern part of Ndiaël, 14 February 2006 (Richard Cruse in Recent Reports, African Bird Club Bulletin)
- One individual feeding close to Richard Toll, March 1st 2018 (Miguel Demeulemeester et al.)
There have been a couple of claims in the past years that refer to other lark species, and probably undisclosed genuine observations as well, as most observations of guided tours remain in notebooks. Most Kordofan Lark records from Senegal should be considered with care when they are not documented.
Kordofan Lark in surrounding countries
In Mali the species is reported as uncommon but widely distributed from 15°N to 23°N by B. Lamarche (1980), adding that the species undertakes local movements with evidence of breeding from May to July near Tombouctou. In mid-June 2004, several Kordofan Larks were in song in sand dunes south-west of Gao, where the spiky grass Schoenefeldia gracilis was dominant (Robert Dowsett & Francoise Lemaire; ABC Bulletin). Similarly, L. Fishpool recorded the song in June in NE Burkina Faso, by a bird “perched on a bush 2m above ground, on sandy soil (mainly of reddish tint)”. This recording was included in the legendary set of sound recordings of African birds by Claude Chappuis (2000).
For Mauritania the following information is given by Isenmann et al. (2010). The Kordofan Lark is thought to be a resident breeder in the Sahelian part of the country. Gee (1984) only found this lark 50-60 km north of Rosso where it was rather common and probably breeding (displaying and diversion behaviours). This location is close to the Senegalese border, and all observations of Kordofan Lark in northern Senegal most likely refer to birds breeding in this area, as there is not yet any evidence of breeding in Senegal. In fact, the species is so poorly known that its nest and eggs remain undescribed.
As written by Nik Borrow & Ron Demey in their reference bird guide, Kordofan Lark is a “small, pale sandy-rufous lark with stout whitish bill and distinctive tricoloured tail pattern (rufous, black and white). When fresh upperpart feathers fringed buff with narrow blackish subterminal crescents”. Its structure is rather similar to Singing Bush-Lark, but the plumage is noticeably different. The picture shows a head and breast pattern that nicely fits the plate in Borrow & Demey, with limited well-defined brownish streaking on the upper breast, sandy-brown head with paler supercilium and nape and a white throat patch extending below the ear coverts. The bird also shows a few fresh scapulars with a neat white fringe and a subterminal dark bar, typical of the species. Its bill also perfectly corresponds with the description given in the Handbook of the Birds of the World, describing the bill as “pale whitish horn, slightly darker tip and dorsal side of upper mandible“. The juvenile is said to have “broader pale feather fringes on back and wing-coverts, heavier dark spotting on breast“.
To sum up, the main characters to look at are the bicoloured bill, brown-rufous upperparts, pattern of fresh upperparts feathers, upperbreast streaking, pale supercilium and the tricoloured tail. These characters are a unique combination amongst larks from the desert.
The group of birds photographed by Tim Wacher show a very pale plumage without breast streaking or contrasting upperparts, an entirely pale bill except for the tip, and no rufous tones in the plumage. At first sight the tail pattern (and length) fits Kordofan, but it lacks the rufous central tail feathers that should be obvious here, and which are clearly visible on the Richard Toll bird. The central tail feathers in the birds below appear more sandy brown than rufous/rusty. These birds also don’t show any white-tipped mantle feathers. As already suspected by Tim, the features shown by these birds thus correspond much more with Dunn’s rather than Kordofan Lark – including the tail pattern, which is quite similar to what can be seen here for example. It’s important to point out (thank you Tim!) that the tail of Dunn’s Lark can apparently also show a considerable variation in length, and that the white margins visible in the photos from Niger are not always evident (or present?).
We’re including the pictures here for comparison purposes, and also because Dunn’s Lark is likely to be found at some point in northern Senegal, given its nomadic habits and that it occurs not far over the border with Mauritania.
Beware also of the possible confusion with rusty females of Black-crowned Sparrow Lark, which can look superficially similar, but show a different tail pattern and proportions. The shorter tail and legs combined with a proportionally large head give a plump silhouette to the bird. Sparrow-larks are also smaller and more compact, and their upper breast is not streaked.
The only other Mirafra species occuring in Senegal is the Singing Bush Lark Mirafra cantillans. This species is fairly common in dry savanna and grassland, and shares some characteristics with Kordofan Lark. The bill can be similarly coloured, the tail can appear tricoloured as well (though less obviously so, and less neatly separated, than in Kordofan – check out variations below) and upper breast is also streaked. In adult plumage the upperparts of Singing Bush Lark is scaly, identification is then straightforward. But in fresh plumage Kordofan Lark shows a scaly plumage as well, thus separating both species can become tricky.
Then what to look at? Global coloration of upperparts seems to be the clue, ground colour being cold sandy-brown for Singing Bush Lark and cinnamon-rufous for Kordofan Lark. Pay also attention to the fresh upperparts feather pattern, Kordofan Lark showing a clear dark subterminal band absent in Singing Bush Lark (this dark line remains on the photographed Kordofan Lark, which shows a fairly worn plumage; this detail is probably only visible at close range). Singing Bush Lark, at least in fresh plumage, typically has a more contrasted head pattern and appears more mottled overall, especially on the mantle and shoulders, with stronger breast streaking than Kordofan.
Obviously, much is still to be learnt about the various Sahelian larks, be it in terms of identification, status & distribution, or ecology!
A few references
Isenmann P., Benmergui M., Browne P., Ba A.D., Diagana C.H., Diawara Y. & El Abidine ould Sidaty Z. (2010). Birds of Mauritania – Oiseaux de Mauritanie. Société d’Etudes Ornithologiques de France, Paris, 408 p.
Morel G., Roux, F. (1962). Données nouvelles sur l’avifaune du Sénégal. L’Oiseau et la Revue Française d’Ornithologie 32: 28-56.
With thanks to Jean-Francois Blanc, Miguel Demeulemeester, Jan Heip, Tim Wacher.
Simon & Bram