Depuis un peu plus de deux mois on a repris nos habitudes au Calao de Ngor cet automne (ai-je vraiment arrêté depuis l’an dernier?), pour voir ce que donne le cru 2018 pour ce qui est de la migration d’automne des oiseaux de mer. Le printemps avait déjà été pas mal, avec entre autres de beaux passages de Sternes voyageuses et de Dougall, de Mouettes de Sabine, et quelques espèces plus rares comme le Fou à pieds rouges, le Puffin de Macaronésie / de Barolo ou encore le Puffin majeur. Ayant eu un peu plus de temps libre et moins de voyages que d’habitude, j’ai donc repris le suivi régulier depuis fin juillet. J’étais curieux notamment de mieux suivre les mouvements en août et septembre, et finalement j’ai un peu mieux pu suivre ces deux mois que l’an dernier: entre le 30/7 et le 30/9, j’ai pu assurer une présence lors de 41 jours, pour environ 55 heures de suivi (2017: 40.5 heures sur 31 jours). A propos de notre suivi de l’an dernier, un article sur le suivi de la migration en 2017 est en cours de rédaction et sera partagé ici en temps voulu!
Les années se suivent mais se ne ressemblent pas: certaines espèces sont visiblement plus communes certaines années, et les conditions météo varient pas mal également. Ainsi, le mois d’août 2018 a été marqué par plusieurs jours de vent favorable (= vent soutenu de l’ouest a nord-ouest), et notamment le Labbe à longue queue a été bien plus nombreux a passer devant les cotes dakaroises qu’en 2017 et 2016. Idem pour les Phalaropes à bec large qui comme le labbe voient eux aussi s’établir un nouveau record journalier.
Comme d’hab’, voici donc une liste comme toujours un peu longue et ennuyeuse, agrémentée de quelques photos d’archives.
Océanite de Wilson (Wilson’s Storm Petrel): au moins 159 oiseaux sont vus entre le 31/7 et le 23/8, avec un max. de 105 en 30′ de suivi le 13/8.
Puffin du Cap-Vert (Cape Verde Shearwater): 97 ind. passent le 11/8 en 2h40′, suivi d’un isolé sur place le lendemain et deux oiseaux le 20/8.
Puffin fuligineux (Sooty Shearwater): comme en 2017, les premiers oiseaux apparaissent des les premiers jours de septembre, mais cette année les effectifs restent très modestes jusqu’à fin septembre: seulement 87 oiseaux du 2/9 au 30/9 alors que dans la même période l’an dernier il en passent 393 pour un effort comparable.
Puffin des Anglais (Manx Shearwater): seuls six oiseaux sont détectés pour le moment, sans doute en raison de l’absence de bonnes conditions météo pour les puffins courant septembre, mois qui devrait marquer le pic du passage de cette espèce.
Puffin “d’Audubon” (Audubon’s Shearwater): à l’inverse, ce puffin généralement très pélagique a été vu bien plus que ces dernières années, avec 19 oiseaux pour le moment. Le premier oiseau passe le 11/8, puis le lendemain c’est un Puffin de Barolo qui est observé en migration active, assez près du rivage permettant son identification. Encore un Barolo ou Macaronésie le 28/8, et le 17/9 il y en a pas moins de 14 qui défilent en deux heures dont quelques groupes de 3-4 oiseaux migrant ensemble. Encore deux le 28/9, et peut-être qu’il en suivra encore quelques-uns dans les semaines à venir.
Fou de Bassan (Northern Gannet): un oiseau de 1ère année passe le 23/9 déjà (2017: premier le 18/9, puis un seul en octobre avant le véritable debut du passage début novembre).
Fou brun (Brown Booby): deux le 26 (un adulte et un imm.) et un imm. les 28 et 29/9 étaient probablement des oiseaux locaux en excursion de pêche depuis les îles de la Madeleine.
Comme je le disais dans l’intro, l’une des surprises de cette saison a été le passage important de Phalaropes à bec large (Red Phalarope) en août: alors que je n’avais noté aucun oiseau avant le 11/8, ce jour-la j’en dénombre pas moins de 825 en 2h40′ de suivi le matin, plus encore 35 en 40′ le soir – apparemment un nouveau record journalier pour le Sénégal, à en croire les chiffres a notre disposition. Plus rien les jours suivants, jusqu’au 18/8 lorsque quelques 65 oiseaux passent en deux groupes – toujours aussi difficiles à estimer! – 37 le 20/8, etc. jusqu’au 2/9. Encore 55 le 17/9, pour un total tout à fait honnête de 1256 oiseaux. Sans doute que plusieurs milliers sont passes au total, loin au large ou invisible entre les vagues. Parmi les autres limicoles, retenons le Courlis corlieu (Whimbrel) avec 415 ind., deux Barges rousses (Bar-tailed Godwit), 28 Huîtriers pies (Oystercatcher) dont 13 ce matin, deux groupes de Bécasseaux maubèches (Red Knot), quelques Tournepierres (Turnstone), un Combattant varié (Ruff), deux Grands Gravelots (Common Ringed Plover) et quelques Chevaliers gambettes et guignettes (Common Redshank & Common Sandpiper).
Mouette de Sabine (Sabine’s Gull): un avant-coureur passe le 30/7 déjà, constituant peut-être bien la premiere observation de juillet pour le site. Passage plus ou moins régulier bien qu’en effectifs très faibles – comme il se doit en août et septembre – du 11 au 22/8 lors d’une période de vents favorables, puis sept le 1/9 et en tout 31 en 2h45 de suivi les 17-18/9. Encore cinq le 24/9 puis plus rien depuis! On attendra donc le gros passage de la deuxième moitie d’octobre pour cette espèce. Peu d’autres laridés pour le moment, mais tout de même à signaler un Goéland leucophée adulte (ou presque) le 23/8.
- Sternes & Guifettes
Sterne naine (Little Tern): 129 individus pour le moment, soit le même ordre de grandeur que l’an dernier à la même periode (idem pour la Sterne caspienne (Caspian Tern), avec 27 oiseaux au compteur).
Guifette noire (Black Tern): avec 4402 oiseaux, c’est pour l’instant la deuxième espèce la plus nombreuse: pas mal d’oiseaux vers la mi-août, puis petit max. horaire de 460 le 18/9. Au moins une Guifette leucoptère (White-winged Tern) est identifiée le 11/8.
Une Sterne bridée (Bridled Tern) est vue en vol vers le NE le 9/8, suivi d’un individu vers le SW deux jours plus tard, et deux oiseaux (adulte et juv.) sur place le 22/8 – probablement des oiseaux ayant niche aux iles de la Madeleine ou au moins 3-4 couples ont été vus en juillet dernier. Plus surprenante, une jeune Sterne fuligineuse (Sooty Tern) passe vers le SW le matin du 17/9, ma première obs de l’espèce ici et en fait première obs tout court – coche √ 🙂
Sterne de Dougall (Roseate Tern): avec 133 Dougall dénombrés, on dépasse déjà d’un tiers l’effectif total de l’an dernier, avec un maximum de 41 oiseaux en 2h de suivi le 17/9. Toujours sympa de voir cette belle espèce, dont le statut de conservation en Europe est plutôt précaire avec des effectifs ne dépassant pas les 1900 couples au début des années 2000, essentiellement aux Açores et en Irlande.
Sternes pierregarin et Sterne arctique (Common & Arctic Terns): 8760 ind., en flot plus ou moins continu depuis le démarrage du suivi. La Sterne arctique était visiblement l’espèce dominante en août et début septembre, mais actuellement la tendance est en train de s’inverser, et la Pierregarin devrait logiquement être la plus commune courant octobre et novembre.
Sterne voyageuse (Lesser Crested Tern): au moins 187, généralement en groupes de 2-3 oiseaux suivant les Sternes caugeks, rarement plus d’une dizaine par heure.
Sterne caugek (Sandwich Tern): Troisième espèce la plus nombreuse, avec 2429 migrateurs pour le moment, dont 2000 passent dans la 2e moitié de septembre.
Sterne royale africaine (African Royal Tern): déjà 897 oiseaux, soit un peu plus du double de l’an dernier. Environ 45% de cet effectif défile pendant la dernière décade d’août, avec des maxima de 136/heure le 25.
Labbe à longue queue (Long-tailed Skua): au moins 478 individus! Le passage débute soudainement le 10/8 – jour d’observation des premiers labbes – avec au moins neuf en 1h30, suivis le lendemain par un bel effectif de 70 oiseaux en 2h40 de suivi et quasiment tous les jours par quelques-uns ou quelques dizaines de migrateurs jusqu’au 22/8. Ensuite rien pendant quatre jours, puis reprise modeste tout à la fin du mois pour culminer le 2/9 avec un effectif impressionant de 217 individus en 1h15 de suivi. Sauf erreur c’est un nouveau record journalier pour le Sénégal, établi en à peine une heure d’observation: combien sont passés en tout ce jour-la? Sans doute plus d’un millier… Cette espèce est bien connue pour ses fluctuations d’effectifs d’année en année: sur les sites de nidification en fonction de l’abondance de nourriture, et visiblement sur les sites d’observation côtiers comme Ngor en fonction des vents pouvant pousser les migrateurs plus près des rivages. En 2017, je n’avais eu que 126 individus; même en prenant en compte l’absence de suivi à la mi-août et pendant plusieurs jours en septembre, il est clair que c’était une “petite” année à Labbes à longue queue, contrairement à 2018.
Labbe parasite (Arctic Skua): 266 individus au compteur, auxquels il convient d’ajouter sans doute une bonne partie des 82 labbes “sp.”; Seuls six Labbes pomarins (Pomarine Skua) pour le moment, avec le premier certain le 30/8.
Labbe de McCormick (South Polar Skua): un oiseau typique passe assez près du bord le 20/9.
Pendant les trois mois qui restent pour cette saison 2018 j’aurai un peu moins de temps que l’an dernier pour suivre ce spectacle de la migration: avis aux amateurs qui souhaiteraient venir en renforts!
Puis il faudrait que je trouve le temps de vous parler de nos sorties récentes au lac Tanma, à la lagune de Yène, et le lac Rose… Mais avant toute chose, demain matin on a prévu une sortie en mer au large de Ngor! Compte-rendu et photos à suivre, si tout va bien.
It’s been a while since I last talked about Technopole on this blog, so here’s a quick update on recent sightings at our favourite Dakar hotspot. I’ve been fortunate to visit several times in the last few weeks, most recently on August 22nd and September 2nd. At the end of August, the site was the driest it’s been in many years: barely any water left on what I usually refer to as the “central lake”. Only some shallow water remained on the far south end along the main road, and even less in the north-east corner close to the golf club house. Even the level of the large reed-fringed lake on the north-east side has dropped substantially.
As a result, there are far fewer birds around than would usually be the case at this time of the year, when the first rains start filling up the lakes again. There are now very few waders, herons and cormorants, hardly any ducks and fairly few gulls and terns (which is more usual during late summer). With the rains finally arriving in Dakar – though just four or five decent showers so far – the site has rapidly started filling up in the past two weeks and is becoming more attractive once again.
This is what it looked like roughly between June and the end of August: hardly any water!!
Despite the low water levels, diversity remains pretty high, with still some 70-75 species typically seen on recent visits. The highlight on Aug. 22nd was yet again a Franklin’s Gull among the flock of Slender-billed Gulls, most likely the same 2nd c.y. bird as in May and June, seen here for the fourth time (see this piece about the species’ status in Senegal and more broadly in West Africa).
Great White Pelicans are particularly numerous this year, with an impressive 650-700 birds present at the moment. They most likely come from the Djoudj colony; unlike in previous years the species is also present daily at Ngor, though in much lower numbers than at Technopole. And a few days ago I even had four flying over the house at Almadies, yet another garden tick.
Besides the ever-present Black-winged Stilts and Spur-winged Lapwings, (both still with several older chicks and quite a few locally hatched juveniles), Ruff is now the most numerous wader, though there are 30-40 birds only… compare with the ∼500 Ruffs counted last year in August! Also just four Black-tailed Godwits (also a Bar-tailed on Aug. 12th), single Whimbrel, Marsh Sandpiper, Dunlin, 4-5 Little Stints and just a handful of Sanderlings, while the first Curlew Sandpipers were seen on Sept. 2nd. On the same day, a Little Ringed Plover was present near the fishermen’s hut – there don’t seem to be many “autumn” records at Technopole of this species. A Kittlitz’s Plover was seen again on Aug. 22nd, following several records in previous months: could the species have bred at Technopole? In June we found a nest containing two eggs and several additional terrtitories near Lac Rose.
On July 7th, a presumed hybrid Little Egret x Western Reef Heron was seen along the track leading to the golf course: interesting bird, as it may mean that there are mixed broods at the Parc de Hann colony, unless of course it was born in the Somone or another heronry. Or that it may be breeding there at the moment, as our bird was obviously an adult in breeding plumage, judging by the pink-reddish feet, bluish lores and long feathers extending from the back of the head. While difficult to judge, the bill length and shape also seems to be more like Little Egret. In addition to the features in the pictures below – in particular the whitish head, central neck and lower belly – we noted a fair amount of white on the wing, mainly towards the base of the outer hand.
Now compare with this typical Western Reef Heron, photographed during my most recent visit to Technopole:
Our bird corresponds to presumed hybrids found in southern Europe and in Morocco, though we can’t rule out the possibility that it is in fact a rare dark morph Little Egret, as these do seem to exist… mcuh remains to be learned about these egrets! For more on the identification of Western Reef Heron and Little Egret, see Dubois and Yésou’s article in British Birds (1995).
Talking of herons, here’s a breeding-plumaged Great Egret: note the entirely black legs and feet as well as the mostly dark bill, with just the some yellow still apparent on part of the lower mandible. The bare skin around the eye and on the lores could be described as pale turquoise, though it transitions from light green to more bluish tones. Quite amazing how these birds completely change the colour of their bill and legs during breeding season!
Besides the above waterbirds, Technopole of course holds lots of good other birds: at the moment, there are a few Broad-billed Rollers that appear to be breeding, and other wet-season visitors such as Woodland Kingfisher and Diederik Cuckoo are also around. And while breeding wasn’t confirmed this year, Red-necked Falcon is still seen on most visits, usually flying around or actively hunting. Zebra Waxbill was more of a surprise, as I’d only seen this species on a few occasions in winter. The lack of rain may have prompted these birds to wander about and somehow make it to Technopole.
Last Sunday I paid an early morning visit to Yène-Tode, but despite the recent rains the lagoon is still largely dry and didn’t hold many birds… The first few puddles had formed, but I reckon it’ll take several more decent showers before the lagoon fills up again. The highlight were two Spur-winged Geese, a species that is rarely seen in the Dakar region and that somehow manages to largely avoid Technopole. To be continued!
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, 22.8 & 20.9.18 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 2018.
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!