The Great Re-Tern

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.

Gulls & Terns at Technopole

 

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.

Colour-ringed Gull-billed Tern & Black-winged Stilts / Sterne hansel & Echasse blanche

 

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!

More gulls & terns

 

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.

A sleepy Franklin’s Gull / Mouette de Franklin

 

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.

 

Greenshank & Black-winged Stilt / Chevalier aboyeur & Echasse blanche

 

 

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27/1/19, journée folle au Technopole

Il y a des jours comme ça!

Après une sortie déjà bien mémorable en compagnie de Simon le 24/1, lorsque nous observons entre autres des Canards chipeaux et un siffleur – tous deux des nouvelles espèces pour le site que Simon avait trouvées la veille – puis d’un Bécasseau de Temminck, Miguel et moi avons pris le temps de bien fouiller notre local patch dimanche dernier. Arrivés à l’aube sur les lieux, nous sommes repartis cinq heures plus tard avec pas moins de 111 espèces au compteur. Pas mal du tout, si l’on considère qu’une visite typique en hiver apporte généralement 70 à 80 espèces. De plus, la journée a été exceptionnelle aussi bien point de vue quantité – il devait y avoir facilement 4’000 oiseaux au Technopole ce jour-là – qu’en termes de qualité, avec plusieurs oiseaux rares et tout à fait inattendus.

Voici donc, in order of appearance, une sélection d’espèces rencontrées:

• Tourtelette d’Abyssinie (Black-billed Wood Dove): un juv. dans le coin nord-est du site était une petite surprise, cet oiseau n’ayant apparemment jamais encore été signalé auparavant au Technopole. En même temps, une Tourterelle vineuse (Vinaceous Dove) chantait dans le cordon boisé juste derrière: espèce numéro 233 pour le site!

Black-billed Wood Dove / Tourtelette d’Abyssinie juv.

 

• Hibou des marais (Short-eared Owl): on pensait qu’ils ne reviendraient pas un deuxième hiver de suite, mais les revoilà! Au moins deux de ces hiboux qui nous avaient gracié de leur présence l’hiver dernier, alors qu’un afflux important se déroulait en Afrique occidentale, étaient de nouveau présents sur leur dortoir favori dans un groupe d’acacias. Ils y avaient déjà été répéres fin décembre par deux observateurs, donc tout indique qu’ils resteront encore jusqu’à fin mars ou début avril avant de repartir pour nicher en Europe.

 

• Bécasseau de Temminck (Temminck’s Stint): déjà vu le 24/1, il ne nous a pas fallu beaucoup de temps pour le retrouver dans le même secteur, se nourrissant en compagnie d’autre bécasseaux. Du coup, nous avons pu observer en cette seule matinée tous les Calidris réguliers du pays: Bécasseau maubèche, cocorli, variable, minute et sanderling – pas mal, non? De plus, ce n’est apparemment que la deuxième obs du Temminck au Technopole, la précédente datant de mai 2015. A peine visibles sur la photo, les pattes jaunâtres en combinaison avec le dessus et la poitrine bruns uniformes sont typiques de ce petit bécasseau, trop souvent confondu avec le Minute. Il est ici tout à fait en marge de son aire de répartition régulière, étant bien plus commun en Afrique de l’Est (au Sénégal, il semble hiverner en petit nombre dans le bas-delta notamment).

Temminck’s Stint / Bécasseau de Temminck

 

• Chevalier à pattes jaunes (Lesser Yellowlegs): alors que je cherchais à mieux observer un pluvier posé parmi les nombreux Grand Gravelots (c’était un argenté…) je vois un chevalier suspect tout près de la piste, se nourrissant activement dans la vase: bec sombre assez court à base légèrement jaune, dessus gris-brun uni, dessous blanc, croupion blanc, et surtout: des pattes jaunes flashant… encore un Tringa flavipes! Serait-ce le même que celui vu l’hiver dernier en février, peut-être même l’oiseau déjà vu en août 2015 et janvier 2016, voire également à Yene en novembre 2017?? En tout cas cette régularité d’observations est intriguante. Comme pour les bécasseaux, nous avons pu observer ce jour tous les chevaliers réguliers au Sénégal, car en plus des habituels des lieux il y avait également deux ou trois Chevaliers arlequins, peu communs ici (Spotted Redshank). En plus de quelques photos relativement nettes pour une fois, on a même réussi à faire un enregistrement de son cri, à écouter ici.

Lesser Yellowlegs / Chevalier à pattes jaunes

Lesser Yellowlegs / Chevalier à pattes jaunes

 

• Goéland de la Baltique (Baltic Gull): probablement la plus grosse surprise du jour, on a été bien étonnés de voir un adulte on ne peut plus typique de cette sous-espèce nominale du Goéland brun: en comparaison directe avec ce dernier, notre oiseau s’en distinguait nettement par sa taille plus petite (sans doute s’agissait-il d’une femelle), son manteau très sombre, presque noir même, et surtout une projection primaire importante lui conférant un aspect bien plus élégant et plus allongé (un peu comme un Pluvier bronzé comparé au Pluvier argenté!). En vol, les ailes longues et plutôt étroites, avec très peu de blanc au bout des primaires externes, étaient frappantes. Malheureusement après un envol général l’oiseau n’a pas été revu, donc pas de photos à l’appui… Notre première obs au Sénégal, ce taxon est néanmoins connu pour hiverner en effectifs très modestes sur les côtes d’Afrique de l’Ouest (quelques individus? pas sûr même que ce soit un visiteur annuel). Sa présence ici, loin de ses quartiers d’hiver réguliers en Afrique de l’Est et l’ocean indien, a été confirmée grace à quelques lectures de bagues notamment en Gambie. Egalement présent dans le tas de centaines de goélands, au moins un Goéland leucophée (Yellow-legged Gull) de 1er hiver, un individu au manteau très clair.

 

• Mouette mélanocéphale (Mediterranean Gull): une dizaine d’oiseaux au moins, soit un peu plus que d’habitude. Comme toujours, l’essentiel des effectifs hivernants est composé d’oiseaux de premier hiver. Pas vu d’oiseaux bagués cette fois-ci, mais on vient de me signaler – merci Renaud – que “RV2L” vu l’hiver dernier a été observé il y a tout juste quelques jours au Portugal.

 

• Canard chipeau (Gadwall): les trois individus trouvés par Simon le 23/1 étaient toujours présents, bien que pas forcément faciles à répérer dans le tas d’anatidés, bien plus compact que quelques jours plus tôt: avec près de 400 Souchets et autant de Sarcelles d’été, cela fait du monde à fouiller… Il s’agit a priori de la première donnée sur la péninsule du Cap-Vert de cet hivernant rare au Sénégal, dont les quelques observations proviennent sauf erreur toutes du bas-delta. On n’a pas vu la femelle de Canard siffleur (Wigeon) cette fois alors qu’elle était assez bien visible les 23-24/1; là aussi il s’agirait d’une première pour le Technopole. Cela fait donc pas moins de 4 ajouts à la liste, et cela en moins d’une semaine.

Gadwall / Canard chipeau

 

• Mouette de Franklin (Franklin’s Gull): encore une obs de ce laridé néarctique! C’est presque devenu banal ici… Un peu loin comme souvent, au repos dans un groupe de Goélands railleurs et Mouette rieuses – bien nombreuses ce jour – j’ai tout de même fait une photo-preuve où l’oiseau, au manteau gris sombre et au capuchon déjà en grande partie noir, est tout juste reconnaissable au milieu du groupe. Entre la photo du Temminck et celle-ci, je ne sais pas laquelle gagnera au concours de la photo la plus pourrie du jour…

Franklin’s Gull / Mouette de Franklin

 

Pour le reste, voir notre checklist eBird (merci Miguel!)

Une fois de plus, le Technopole confirme sa position de haut-lieu de l’ornithologie sénégalaise, et de hotspot urbain tout à fait exceptionnel. A voir ce que nous apporteront les prochaines visites!

 

White-rumped Seedeater / Serin à croupion blanc

 

 

 

 

 

Unseasonal visitors…

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).

Purple Heron / Héron pourpré imm., Mbeubeusse, June 2018

 

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.

Mottled Swift / Martinet marbré, Niokolo-Koba NP, 20.2.18 (P. Albrecht)

 

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?

European Bee-eater / Guêpier d’Europe (seen here on wintering grounds in coastal Casamance, March 2017)

 

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…

Melodious Warbler / Hypolaïs polyglotte, Niokolo-Koba, June 2018 (G. Caucanas)

 

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).

Woodchat Shrike / Pie-grièche à tête rousse, near Diourbel, June 2018

 

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!