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).
Les fous des Iles de la Madeleine, j’en avais déjà parlé ici, en décembre 2016, pour faire le point sur le statut du Fou brun dans la région. Ce superbe oiseau marin est, depuis, signalé quasiment lors de chaque sortie au “PNIM” et plus particulièrement entre octobre et mai, et on le voit de temps en temps passer ou pêcher devant Ngor. Pas encore d’indices probants de sa nidification, mais ce n’est peut-être qu’une question de temps… voir plus bas.
Cette fois, c’est d’un autre fou dont il s’agit, et pas de celui que vous pensez – des Fous de Bassan, il y en a plein qui passent l’hiver dans les eaux dakaroises, et en ce moment même on les voit facilement de part et d’autre de la péninsule, que ce soit à Ngor ou devant les Mamelles.
En effet, il s’avère qu’un fou photographié le 26 janvier dernier par un groupe d’ornithos canadiennes (équipe 100% féminine, c’est assez rare chez les ornithos pour le souligner!), était en fait un Fou à pieds rouges (Red-footed Booby), et non un Fou brun (Brown Booby) comme initialement identifié. C’est grâce à une remarque laissée par un utilisateur d’eBird ayant mis en doute l’identité (« semble avoir les pieds étonnamment rouges pour un Fou brun! »), que la donnée est passée dans la liste à valider sur eBird, liste que je scrute de temps en temps en tant que vérificateur pour le Sénégal.
Et effectivement, l’oiseau pris en photo montre bien un Fou à pieds rouges, un individu de forme sombre – et qui du coup ressemble pas mal au Fou brun (et dont un oiseau était présent le même jour). Il se tenait sur la fameuse balise rouge et blanche qui sert très souvent de reposoir au Fous bruns, situé un peu au nord-est des îles.
L’identification est relativement facile ici, d’une part parce qu’on voit encore tout juste les pattes roses, d’autre part parce que le plumage est brun uniforme y compris sur le ventre, sans contraste (même flou) comme chez les Fous bruns immatures. De plus, le bec relativement court et peu épais pour un sulidé, avec une base rosée et un cercle orbital bleu, est typique pour l’espèce. Notre oiseau montre également un front légèrement bombé, alors que chez le Fou brun il n’y a quasiment pas de front: la base du bec épais est dans la prolongation directe de la calotte, rendant la tête moins rondouillarde que chez le brun.
L’âge par contre est moins facile à déterminer: très probablement un immature, car le bec n’est pas bleu mais plutôt gris sur fond rose et peut-être que la couleur des pattes (rose et non rouge vif) est également un signe d’immaturité.
A comparer maintenant avec le Fou brun immature : ci-dessous, un oiseau d’un voire deux ans, ici en avril 2017 en compagnie de deux adultes. Les critères le distinguant du Fou à pieds rouges de forme sombre sont notamment la couleur des pattes et du bec, le contraste entre d’une part le ventre plus clair et d’autre part la poitrine et le dessus sombres, ainsi que la coloration générale plus sombre et moins pâle que son cousin à pieds rouges.
C’est seulement la deuxième donnée de l’espèce au Sénégal, donc c’est loin d’être anodin comme observation! La précédente date d’octobre 2016, lorsqu’un oiseau est observé au cours d’une sortie en mer en marge du PAOC, à une vingtaine de kilomètres au large de Yoff – les détails de cette première observation pour le pays seront publiés dans le prochain bulletin de l’African Bird Club, à paraitre en septembre et que l’on partagera en temps voulu (Moran N. et al., First record of Red-footed Booby Sula sula for Senegal, voir photo ci-dessous).
Le Fou à pieds rouges est une espèce marine tropicale plutôt répandue, et est classée non menacée par l’UICN bien que la population globale soit considérée comme étant en déclin. Les colonies les plus proches se trouvent sur l’île d’Ascension dans l’Atlantique Sud et sur l’archipel Fernando de Noronha (NE du Brésil). Il hiverne sur des îles tropicales sur tous les océans, en gros entre les deux tropiques.
Jusqu’à récemment l’espèce était un visiteur rare aux Îles du Cap-Vert, mais en octobre 2016, au moins 17 individus étaient présents à Raso, puis en octobre 2017 apparemment une centaine!! Autant dire que c’est l’explosion des effectifs, même si aucune nidification certaine n’a été rapportée pour le moment – du moins pas à notre connaissance. On peut donc s’attendre à d’autres observations dans les eaux sénégalaises à l’avenir, et j’espère bien sûr le voir un jour passer devant le Calao ou encore au PNIM. [addendum du 17/5/18: ce matin j’ai eu la chance d’en voir deux en train de pêcher longuement devant Ngor, non loin du rivage! Je ne pensais pas que je verrais l’espèce aussi rapidement…]
Ailleurs dans la région, Sula sula a été vu devant les côtes mauritaniennes (au moins un en oct.-nov. 2012), et des individus ont été signalés aux iles Canaries, aux Açores, et à Madeire. L’espèce est très rare plus au nord, avec p.ex. tout juste deux observations en France (un sur le lac de Sainte-Croix dans les Alpes-de-Haute-Provence en juillet 2011, puis un en juin 2017 en Bretagne dans la colonie des Fous de Bassan des Sept-Iles – voir l’article sur Ornithomedia). Ou encore cet oiseau trouvé épuisé sur une plage de l’East Sussex en septembre 2016, le premier pour la Grande-Bretagne.
Je reviens encore brièvement sur les Fous bruns, car samedi dernier (14/4) lors d’une visite aux Iles de la Madeleine nous avons pu observer de nouveau au moins sept individus : cinq posés dans leur falaise habituelle des îles Lougnes¹ (trois adultes, un subadulte, et un jeune au plumage similaire à celui de la photo d’avril 2017), puis encore deux adultes sur la fameuse balise marine, en train de parader lorsque nous passons à côté en bateau… Situation très similaire voire identique donc à celle d’avril-mai 2017, et toujours aussi intriguante: à quand la première nidification de l’espèce? Ci-dessous encore une photo médiocre de quatre de ces oiseaux dans leur falaise, prise lors de notre visite la plus récente, pour vous donner une idée.
Samedi dernier il restait encore quelques Fous de Bassan, deux Courlis corlieux et deux Balbuzards, mais sinon peu d’oiseaux sur l’île. Lors de la traversée depuis Soumbedioune on a pu voir un Océanite de Wilson passer tout près, un Labbe pomarin, et plusieurs sternes (Dougall, arctique, pierregarn, caugek, voyageuse et royale) ainsi que quelques Guifettes noires en migration active (Northern Gannet, Whimbrel, Osprey, Wilson’s Storm-Petrel, Pomarine Skua, Roseate, Arctic, Common, Sandwich, Lesser Crested, Royal & Black Terns). Et bien sûr les Phaétons à bec rouge, emblème du parc, dont la nidification bat encore son plein; on a d’ailleurs eu la chance de renconter l’experte Ngoné Diop en train de faire le suivi de la colonie, qui abriterait cette saison au moins 40-50 couples nicheurs (Red-billed-Tropicbird).
Merci aux observateurs tout d’abord: Hélène Gauthier, Marie O’Neill, Lorraine Plante, Diane Thériault. Et à Nick Moran et Barend van Gemerden pour avoir fourni les photos et la version finale de l’article sur la première observation sénégalaise. Et enfin, à tout seigneur tout honneur: c’est Brennan Mulrooney qui à signalé la donnée sur eBird, sans quoi elle aurait bien pu passer à travers les mailles du filet!
¹ Les îles Lougnes sont cees îlots rocheux inaccessibles faisant partie du parc national, photo ici.
(see also this Ornithondar post on the same topic, en Français!)
Back in January, when Frédéric Bacuez (Ornithondar), Filip Verroens and I visited the middle Senegal valley, we stayed the night at Gamadji Sare on the Doue river bank in the far north of the country. We had some really good birds here, such as Egyptian Plover, Red-throated Bee-eater, Fulvous Babbler, Cricket Warbler, and Seebohm’s and Isabelline Wheatears. We also encountered a flock of swifts which we initially took for White-rumped Swift as these had been reported from the Senegal valley before and since in Senegal this is the only swift with a white rump other than Little Swift.
However, something felt not quite right for this species, and luckily Frédéric was able to take a number of decent pictures – not an easy feat with these birds! Subsequent study of the pictures revealed that the birds did indeed not quite fit White-rumped Swift, and that they were something else… Frédéric was lucky to pay a second visit to the same site, in mid February, and despite very dusty conditions he obtained even better pictures. These provided a more definite clue to the identity of these mystery swifts, which we now feel confident are nothing less than HORUS SWIFTS!!!
Why do we get so excited about this one? It’s always exciting of course to find an addition to a country’s species list, but in this case we have a highly unexpected record since it comes down to a range extension of no less than 1,600 km, and because the species may even breed here. Plus, one can now safely assume that Horus Swift also occurs in Mauritania, Mali and Burkina Faso, and why not in northern Cote d’Ivoire and NE Guinea too (and for any WP listers out there: it may well make its way across the biogeographical border!). It also shows, once again, that there’s still so much to learn and to be discovered about birds in Senegal despite it being among the better explored countries in West Africa.
So far, the closest Horus Swift observations to Senegal were from Ghana, more precisely from Mole National Park and a few other locations in the NW of the country where they were first found in 2004, though it’s not clear whether these were incidental records of wanderers or whether the species is a resident here. It has also been recorded from SW Niger (‘W’ NP), several plateaux in Nigeria and the highlands in Cameroon, but only becomes relatively widespread in the highlands of East and Southern Africa.
On hindsight, the identification as Horus Swift is actually relatively straightforward, the key id features of Horus Swift being the following:
- Broad rectangular white rump patch extending well onto the sides of the lower flank (not narrow and U-shaped as in White-rumped)
- Moderately forked tail, intermediate in depth between Little and White-rumped Swifts
- Absence of white trailing edge to secondaries (a feature that’s almost always present in White-rumped)
- Overall structure and flight action closer to Little than White-rumped Swift, which is a slender bird with a graceful flight.
All of these are clearly visible on the pictures, some of which are shown below (merci Fred!). The option of a hybrid Little x White-rumped Swift was initially suggested, but all features fit Horus perfectly, and a hybrid would be slimmer with a smaller throat patch and some white edges to secondaries. Plus, it would be (near) impossible to have 18-20 hybrids together, without any pure birds. All swifts looked similar in the field, though pictures reveal that there may have been a Little Swift in the lot as well (picture here). A presumed hybrid was reported from Spain recently, see this eBird record. Our identification was confirmed by Gerald Driessens, illustrator of the reference guide to the swifts of the world.
The next three pictures are from February 12th, i.e. some five weeks later than our first observation when Frederic and Daniel Nussbaumer visited the site. Only a few birds were present, at least one of which showed a heavily worn plumage, see picture (6). Besides the shallow tail fork and large rump patch, the extensive white throat patch extending onto the upper breast is obvious here.
Here’s a more detailed description, largely based on the ca. 50 pictures by Frédéric :
Structure: typical swift build with a body shaped like a fat cigar and long and pointy wings, and a moderately forked tail, the fork being about a third of the length of the outer rectrices when closed.
- The wing shape resembled Little Swift much more than White-rumped, which has narrower wings. It often appeared to be fairly broad, particularly in the middle (inner primariers and outer secondaries). As can be seen on several of the images, the wing shape varied considerably throughout the birds’ flight action – for instance, compare pictures (3) and (4) which give very different impressions, and see also (8).
- The tail always appeared to be broad throughout, never pointed as is often the case in caffer (1) & (2). When completely fanned out, the fork appeared very shallow, quite similar to House Martin (2). At times it disappeared nearly entirely, thus resembling Little Swift: compare (6) and (7), of the same bird taken at an interval of a few seconds.
- Overall very dark brown to black plumage except for the white throat, the very pale forehead extending to just above the eye (4), and the white rump;
- The rectangular white rump patch (4) clearly extended onto the flanks and was thus visible from below, e.g. pictures (5) and (6).
- The throat patch was similar to or larger than Little Swift, obviously extending onto the upper breast. Both features are nicely visible on (6) and to some extent on (1).
- Several photographs clearly show the relatively contrasting underwing pattern, stemming from a combination of paler brown leading edge-coverts, dark lesser underwing coverts, again paler median coverts, and slightly darker greater coverts – see header picture and (3) and (6). In White-rumped Swift, the lesser and median coverts are all darker than the remainder of the underwing.
- Upperwing entirely dark, without white trailing edge to secondaries. The latter appear slightly greyer or browner than the black mantle and scapulars (the “saddle”).
Voice: slightly lower-pitched trills than Little or White-rumped Swift; the short sound recording that I managed to obtain can be found here and contains two different calls, including a typical shrill swift call and a slower “twittering” of more melodious quality. It matches the recording by C. Chappuis quite well, both by ear and on sonogram, even if I find it hard to hear clear differences with some White-rumped Swift recordings (compare with e.g. this recording from Zambia). HBW describe the most common Horus call as a reedy trilled ”prrreeeeoo” or “prrreee-piu”. Of note is that until now, no recordings were available on xeno-canto or other online sound libraries.
Behaviour: the swifts were mostly feeding over the river and nearby banks, though usually remained above the water at various heights, occasionally flying right above the surface. They mostly remained in a loose flock, sometimes with 2-5 birds flying closely together and swooping close to the sand bank above which we were standing, sometimes calling in the process – a behaviour that’s indicative of breeding… The picture below shows two such birds “chasing” one another.
Below are a final few pictures from the January series:
Now compare with these pictures:
- Horus Swift
- White-rumped Swift
The habitat in which we found these birds is also very much in line with what is to be expected from Horus Swift. Quite unlike most (all?) other swifts, the species breeds in “old burrows of bee-eaters, kingfishers and martins” (Borrow & Demey), i.e. typically in sandy banks along rivers – exactly the kind of place where we found these birds, which were seen “visiting” the Gamadji Sare cliff (approx. 6-8m at its tallest). Our swifts either rested on the cliff, or inside holes: at dawn on 6/1, several birds visibly left the river bank while the previous evening they were flying very close to or into the cliff, oftentimes calling (unfortunately, because we were positioned on top of the cliff, we could not confirm that they actually entered any nest holes). We estimated there to be about 18-20 birds on Jan. 6th, while the previous afternoon we saw just four.
It may thus even breed by the Doue river which likely has Pied Kingfisher and Blue-cheeked Bee-eaters, and possibly also Red-throated Bee-eater nesting here – something that we really ought to confirm in coming months (just before, during, or right after the rains?). White-rumped Swift typically breeds in disused swallow or Little Swift nests, though sometimes also “in crevices or on ledges within rock fissures or buildings” (Chantler & Driessens 1995). It may well breed at Popenguine for instance, where in September 2015 I saw two birds entering and leaving one of the World War II bunkers.
As I was typing this up, I started wondering why a rather unassuming little bird such as this one was named after one of the most significant ancient Egyptian deities. Well, I’m not quite sure! It was described in 1869 by German zoologist Theodor von Heuglin, who spent many years in north-east Africa in the mid-19th century. One can assume that he collected the type specimen in Sudan or especially in Ethiopia where Horus Swift is locally fairly common. And that Heuglin somehow must have been inspired by Horus, depicted as a falcon-headed man, when coming up with a name for this species.
Many thanks to François Baillon, Simon Cavaillès, David Cuenca, Ron Demey, Gerald Driessens, Miguel Lecoq, Carlos Sánchez and others who commented on the identification or provided reference material.
Bram & Frédéric (une co-production Senegal Wildlife & Ornithondar!)
- Chantler, P. & Driessens, G. (1995) Swifts. A Guide to the Swifts and Treeswifts of the World. Pica Press.
- Chantler, P. & Boesman, P. (2018). Horus Swift (Apus horus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
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
Routine Technopole visit this morning, with a a few good birds to report and (most importantly) a correction to be made.
With water levels now very low, most waders, gulls and terns are now concentrated in the SW part of the main lake and along its northern edge. After an initial scan from behind the fishermen’s cabin (African Spoonbill, Yellow-billed Stork), I made my way to where most of the smaller waders were feeding, and soon located an American Golden Plover, an adult moulting into breeding plumage. The contrasted plumage, long wings (clearly extending beyond the tail tip), and smaller and more slender build than Grey Plover made the identification pretty straightforward, even at long range as in the record shot below:
This is now the fourth record in three years at Technopole, all of which have been in spring (8/4-21/5) and all birds so far have stayed for several days or weeks, so it’s likely that this one will hang around a bit longer. And going by last year’s series of observations, it may well be joined by other AGP’s in coming weeks – no doubt are there several birds wintering in (West) Africa each year, and some of these will pass through the Dakar penninsula. Previous Technopole records were in June 2012 (M. van Roomen) and October 2005 (Nillson et al., W. Faveyts) and there’s also an observation from lac Mbeubeusse in March 2013, by Paul Robinson.
The image below is a bit less distant, and clearly shows the dark upperparts speckled with fresh golden mantle feathers, a contrasting white supercilium wrapping around the ear coverts, an “open” face due to pale lores, the thin bill and especially the very long primaries, extending well beyond the tail. Note also the black feathers appearing on the lower breast.
Despite not having relocated the White-rumped Sandpiper during my two previous visits, I still had this bird in the back of my mind, so was pleased to see it again, this time not too far. I was determined to see the white rump as we hadn’t clearly seen it two weeks ago, and as such a slight doubt remained as to whether we could safely rule out Baird’s. It didn’t take long for the bird to fly off, and now I clearly saw the rump: no white!!! This was confirmed when the bird took off a second time. So it was a Baird’s Sandpiper after all… which means we somehow got tricked into believing we saw white on the rump during our initial observation (wishful thinking? a Curlew Sandpiper?), at least that’s assuming that we’re talking about one and the same bird here. It does explain why we felt that several features on the pictures from 25/3 were pro-Baird rather than White-rumped Sandpiper.
So, still no Calidris fuscicollis in Senegal, but we’re pretty happy with Calidris bairdii as well – I’d never seen either species before, and Baird’s has been seen only once before in Senegal, in 1965 (!), though I still need to find out exactly when, where and by whom.
I’ve updated and renamed the original post with some more details.
Other than these, there are a couple of Dunlins around, still several Curlew Sandpipers (some now in full breeding plumage), a Spotted Redshank, a couple hundred Common Ringed Plovers, a handful of Sanderling (much less than just over a week ago), a Whimbrel, a Greater Painted-Snipe, etc.
Unlike earlier in the week, I didn’t see any Mediterranean Gulls and the majority of Black-headed and Lesser Black-backed Gulls seem to have left the area by now. The various flocks of terns held Arctic, Common, Caspian, African Royal, Lesser Crested, Sandwich, and Gull-billed Terns! A few Black Terns were flying around (while Roseate and Little Terns were seen in the last few days from Ngor, so that’s almost all regular tern species that are present in Dakar at the moment). A few Eurasian Spoonbills are still around, including one on 1/4 with a white ring “AVLV” from the Camargue program – awaiting details on this bird’s life history.
A Marsh Harrier hunting over the area was probably one of two birds that spent the winter at Technopole, while a kestrel passing through quite high was visibly actively migrating and may well have been a Lesser Kestrel, though not sure.
Still lots of Black-crowned Night-Herons, but with the water levels being so low there aren’t many other herons around, just a few of each of the regular species incl. a few Black Herons. And most of the northern songbirds are gone now, with just a few Yellow Wagtails still around. A pair of Copper Sunbirds was singing and feeding in mangroves not far from the Club House, and has been seen several times in the same area in recent weeks. Also still lots of Sudan Golden Sparrows, while the Black-headed Weavers are now in full breeding plumage and are actively nest-building, and Northern Crombec has been heard singing on most recent visits.
This post – including its title – was modified on 8/4 after we found what is supposed to be the same bird, and re-identified it as Baird’s Sandpiper rather than White-rumped.
Last Sunday (25/3), during a routine Technopole visit with Miguel and Antonio, we picked up an odd looking sandpiper among a group of Common Ringed Plovers. Slightly yet noticeable larger than the numerous Little Stints that are currently present, it mainly stood out by its peculiar elongated shape, due to its long wings projecting well beyond the tail tip: could it be a Baird’s or White-rumped Sandpiper?
Adrenaline levels rising fast, we quickly tried to get some pictures while studying the bird. When it moved next to a Little Stint, we could clearly see that this was not just another oddly shaped Little Stint but something different, and that it could only be one of those two American waders. It was closer in size to Common Ringed Plover, appearing intermediate between Little Stint and Dunlin. The bird was actively feeding now, probing for food in the mud, and we could see the moderately long and clearly down-curved bill (longer than Little Stint, but shorter than Dunlin), a faintly streaked breast, white underparts, brown-grey upperparts with some new scapulars in an otherwise seemingly very worn plumage. And then that elongated body shape combined with short black legs giving it a silhouette and posture unlike any other calidrids I’d seen thus far.
Then it took off – maybe because of yet another Peregrine blitz – and even though views were brief and quite distant, we each thought that we saw that the rump was mostly white (in fact it’s the uppertail coverts, but “White-uppertailcovered Sandpiper” somehow doesn’t sound quite right). This clinched the id for us even though none of use were fully familiar with the subtle differences between Baird’s and White-rumped, other than the difference in uppertail / rump pattern. I found what was most likely the same bird again on 8/4 (after not seeing it on two previous visits), and this time got much better views including of the rump in flight, which was not white at all: Baird’s Sandpiper!! So not a White-rumped after all… It just shows how one false impression in the field can lead to wrong conclusions, and that you should not take our id’s for granted! And that we still have lots to learn. It also explains why we were confused and felt that the bird looked more like Baird’s, but given that we thought we saw a white rump we could only announce it as a fuscicollis… Maybe when we saw the bird flying, rather in the distance, we were in fact somehow looking at a Curlew Sandpiper.
The distant pictures that follow show an overall fairly brown sandpiper with a diffuse yet clearly demarcated breast band and otherwise white underparts, a feature that actually fits Baird’s more than White-rumped. However, the pictures may be somewhat misleading as the impression in the field was of a slightly paler and colder-toned bird with less uniform plumage – for instance, the upper breast was finely streaked, incl. on the upper flanks. Some mantle feathers had already moulted and the crown was very finely streaked. That said, it appears that White-rumpeds in winter can have quite a bit of variation, some birds being browner overall and (almost) lacking any streaks on the flanks that are otherwise considered to be typical of the species – we found pictures of a few such birds online, e.g. here (IBC) as well as in this useful series of Baird’s and White-rumped from their wintering grounds in Argentina (beware though of the second Baird’s picture, which I think is actually a White-rumped Sand’). We suspect that this was a first-winter bird starting to moult into its first summer plumage, though without better pictures we can’t rule out that it was a full adult.
The bill shape appears subtly different from one picture to another, but the first photograph is probably the most accurate: fairly thick at the base and slightly curved. This fits Baird’s quite well, though many birds appear to have a more straight bill than this one (another reason why we were lead to believe it was White-rumped!).
The long wings, crossed like scissors, are quite well visible on this picture, as is the overall “flat” appearance of the species. The whitish supercilium extends well beyond the eye, a pro-fuscicollis feature, but apparently still ok for Baird’s. One may expect the primary projection to be longer, but there again there seems to be quite a bit of individual variation.
Unfortunately, the rump can’t quite be seen in this picture:
A useful discussion on separation of Baird’s and White-rumped Sandpipers, even if it mainly focuses on birds in summer and autumn when most likely to show up in the UK, is to be found here. The European and North American field guides were surprisingly unhelpful when it comes to describing the variation in winter plumage of both species. I thus turned to Faansie Peacock’s excellent field guide to the Waders of Southern Africa, which provides a more relevant Southern Hemisphere perspective on wader identification. Along with the author’s other publications (LBJs, Pipits of Southern Africa) this easily ranks among the finest bird guides that are currently available¹. Let’s just hope that ornithodippiasis doesn’t get the better of him and that he can author many more books.
We moved to the main track as we were hoping to relocate our sandpiper given that it seemingly had landed in the area. After careful scrutiny of the numerous Little Stints, Curlew Sandpipers and Common Ringed Plovers (and finding a Buff-breasted Sandpiper in the process!), we ended up seeing it just as we were about to give up. Even worse pictures followed (distance, heat haze are the usual excuses) and the bird settled down to sleep, so we eventually moved on as we still wanted to check the other side of the main lake (where we saw Short-eared Owl and Copper Sunbird; other good birds at Technopole included an imm. Yellow-billed Stork, African Spoonbill, and Mediterranean Gull).
Here’s a picture from this morning 8/4, where the bill appears less curved and thinner at the end, and it clearly is all black (which all fits Baird’s perfectly):
Baird’s is a rare vagrant to Africa, with just a single claim from Senegal (Dec. 1965 in or near the Djoudj, as per Borrow & Demey, but I could not find the original reference so far), one from The Gambia (Nov. 1976), plus a record from November 1987 in Nouakchott but which was not retained by Isenmann et al. As such it seems that our bird is the first record for the subregion.
White-rumped Sandpiper is equally rare, with most continental records from South Africa during winter. In West Africa, there appear to be just a handful of records: one from Cote d’Ivoire (Oct.-Nov. 1988), and two from Ghana (Dec. 1985 & 2012). Given that it’s relatively frequent in Western Europe in autumn, and that in the Cape Verde and other East Atlantic islands the species is also quite regular, surely they must be pretty much annual visitors to West Africa. More generally, one can only speculate how many American and other vagrants truly pass through Senegal each year.
Both species are long-distance migrants, breeding in the Nearctic tundra, and spending the winter in South America.
The same goes for the Buff-breasted Sandpiper; this bird was likely one of the two that were seen on most visits between 13/1 and 19/2, but then again it may also have been a new bird that was just passing through.
So now we just need to find a proper Calidris fuscicollis, and finally add it to the national list.
In fact, how many bird species have been sighted in Senegal thus far? We’ll try to answer that question in a future blog post!
¹ Peacock, F. 2016. Chamberlain’s Waders. The Definitive Guide to Southern Africa’s Shorebirds. 256 p., Pavo Publishing. See the author’s website for more info.