As is now a bit of a tradition on these pages, I’m again compiling a review of last year’s main birding events. Senegal’s bird year 2019 was a pretty good one, with the usual decent mix of new discoveries, rare vagrants, scarce migrants, range extensions and new breeding records.
First things first: last year saw the addition of two new species to the country’s avifauna, so rather similar to previous years – on average, there have been two additions per year during 2014-2018. First a Willcock’s Honeyguide in Dindefelo nature reserve found by Nik Borrow and his group in January, then the discovery of a small group of Cuckoo Finches at Kagnout in Casamance, in February by Bruno Bargain, Gabriel Caucal and Adrien de Montaudouin. As predicted back in 2018, both Dindefelo and Casamance are obviously key areas for finding new birds in the country. Both species are known to occur in neighbouring countries so these additions are not too much of a surprise, and will likely show up again in Senegal in coming years. These “firsts” bring the total number of species confirmed to occur in Senegal to 674, with seven additional species listed as requiring confirmation. The full checklist as per IOC taxonomy (v.8.1) may be found here.
Next up, the usual lot of vagrants: from North America, the now annual American Golden Plovers (Palmarin in April, and Yene in December), the country’s fourth Pectoral Sandpiper at Lac Mbeubeusse on 5.10, and a Lesser Yellowlegs wintering at Technopole – apparently the longest stay recorded in Africa (at least 71 days!), and most likely the same bird seen several years in a row now. Two Laughing Gulls that were present at Technopole in April-May – an adult in breeding plumage and a first-summer bird – were the 6th and 7th records; the immature was also seen at Ngor on 22.5. Also at Technopole were at least two different Franklin’s Gulls, one in January and two in April-May including an adult displaying to other gulls. A Lesser Jacana was found by Vieux Ngom on 16.3 on the Lampsar, while a Spotted Creeper on 17.12 at Kamobeul (Ziguinchor) was another rarely recorded Afro-tropical vagrant. And finally from Europe, a Little Gull – possibly not a true vagrant but rather a very scarce winter visitor – was seen on 8.3 at Ngor, and a European Golden Plover was at Saloulou island (Casamance) on 25.2.
Scarce migrants included a few species of ducks that are rarely reported from Senegal, starting with these three Gadwalls found by Simon Cavaillès at Technopole in January, which were probably the same birds as those seen in December 2018 in The Gambia. A Eurasian Wigeon was present at the same time; while the latter is regular in the Djoudj, both ducks were apparently seen for the first time in the Dakar region.
Almost a year later this pair of Ferruginous Ducks on a small dam at Pointe Sarène near Mbour on 24.12 were a real surprise in this location. Apparently they didn’t stick around: earlier today (19.1.20) I had the chance to visit the dam again but no sign of our two Palearctic ducks…
An African Crake found by Miguel Lecoq in a dry river bed at Popenguine NR on 12.7 was highly unusual. The two Short-eared Owls at Technopole in January (with one still here on 11.2) were possibly returning birds from the 2017-18 influx as they roosted in exactly the same location; another bird was found in the Djoudj on 26.12 by Vieux and Frank Rheindt. Perhaps more unexpected was a Marsh Owl that was actively migrating at Ngor on 8.10, coming from the north out at sea, but even more spectacular was the discovery of an Egyptian Nightjar by Frédéric Bacuez on his local patch at Trois-Marigots, on 23.10 (an early date and first in this location); in the Djoudj NP, a somewhat classic location for the species, three birds were seen several times from 23.11 up to mid December at least.
A few Red-footed Boobies were again seen at Ngor: an adult on 3.7 and likely the same bird again on 22.7, then daily from 9-12.8 (with two here on 17.8), and again an imm. seen twice in November. These are the 5th to 7th records, a remarkable presence given that the first record was in October 2016 only! As usual, several Brown Boobies were seen as well but we didn’t get the chance to properly check on the birds at Iles de la Madeleine this past year. Other scarce seabirds seen from Ngor were a Balearic Shearwater (18.11), a Bulwer’s Petrel (5.12), several Leach’s Storm-Petrels (11 & 13.11), and some 30 Barolo’s/Boyd’s Shearwaters that passed through in August and September. A Baltic Gull (fuscus Lesser Black-backed Gull) at Technopole 27.1 was our first record here.
Quite a few birds were reported for the first time from Casamance by Bruno and friends, and several resident forest species that had not been seen in many years were “rediscovered” this past year, such as Black-shouldered Nightjar, Black Sparrowhawk, White-throated and Slender-billed Greenbuls, Flappet Lark, Red-faced and Dorst’s Cisticolas – the online Casamance atlast can be found here. Several Senegal Lapwings were again seen towards the end of the rains, and a Forbes’s Plover at Kagnout on 17.2 was definitely a good record as the species had previously been reported only on a few occasions from the Niokolo-Koba NP.
A Brown-throated (= Plain) Martin feeding over the lagoon at Technopole on 28.4 was a first for Dakar; this species is rarely seen in Senegal it seems. A few Moltoni’s Warblers were reported in autumn including at least one on 20.10 at Mboro, where Miguel also noted several northward range extensions such as Fine-spotted Woodpecker, Grey Kestrel, Splendid Sunbird, and Orange-cheeked Waxbill. The observation of two Mottled Spinetails some 15km south of Potou (Louga region) is the northernmost so far and seems to confirm the presence in this part of the country, following one in the same region in January 2018. A pair of Little Grey Woodpeckers at Lompoul and the discovery of Cricket Warbler in the Gossas area (Diourbel) are also noteworthy as they are just outside known distribution ranges for these two Sahelian species. More significant is the observation of a Long-billed Pipit on the Dande plateau near Dindefelo on 9.2, as this is the first record away from the Djoudj area, raising the possibility that the species is breeding in the vicinity.
Additional good records for the Dakar region included a White-throated Bee-eater on 12.8, a Red-breasted Swallow near Diamniadio on 11.10 and Grasshopper Warblers at Yene lagoon on 8 & 15.12, as well as at Lac Tanma (Thiès region) on 27.10 – and more surprisingly, one was found aboard a sail boat some “400 Miles South West Of Dakar” on 13.9. Last year we documented oversummering of Yellow-legged and Mediterranean Gulls on the peninsula.
We also continued our modest efforts to survey breeding Black-winged Stilts at several sites in Dakar, Ziguinchor and Saint-Louis; the findings of these should be formally published later this year. The Horus Swift colony was visited on several occasions (Jan.-March and Nov.-Dec.) with further evidence of breeding. A pair of Tawny Eagles at their nest site on a high tension pylon near Ndioum, where they are known since at least 2015, were seen again in December by Frédéric and Jérémy. Yellow-throated Longclaw was found to be breeding at lac Mbeubeusse and probably at lac Rose as well: more on the species in this post.
In July we found several additional pairs of Turati’s Boubou right on the border with Guinea-Bissau, a bit further to the south of the site where Bruno initially found the species, in October 2018 near Ziguinchor. Also in Casamance, breeding was confirmed for Common Buttonquail, Golden-tailed Woodpecker, and a whole range of other species.
Another noteworthy record is that of a group of 113 Eurasian Griffons in the Djoudj NP on 2.11 – apparently the largest flock ever recorded in Senegal! This surely reflects the general increase in numbers of what used to be a rather scarce species it seems – read up more on the status of this vulture in Senegal in this post on Ornithondar.
As usual, a few interesting ring recoveries were obtained, including several returning birds, providing further evidence for site fidelity and local movements between key sites for e.g. Black-tailed Godwits and Ospreys of course, but also for a Eurasian Spoonbill from Spain – more on this in a future post. A Gull-billed Tern from the Neufelderkoog colony in northern Germany was also a good recovery, just like the many Sandwich Terns that we managed to read at Technopole in April-May with birds originating from Ireland, the UK, the Netherlands and Italy! Also of note were a French Black-headed Gull, the first colour-ringed Greenshank and wing-tagged Marsh Harrier in our ever-growing database, and last but not least the first recovery of a Croatian-ringed bird in Senegal, an Audouin’s Gull seen at three sites in Dakar in January and February.
During 2019 I was fortunate to continue our regular coverage of Technopole but also for the third consecutive year of seabird migration at Ngor, and managed a few trips further afield: the northern Saloum delta (Simal, Palmarin), three trips to Casamance (January, May, July), the Petite Côte (at long last explored the lagoons at Mbodiene!), the Langue de Barbarie and Trois-Marigots in April, the Djoudj and other parts of the lower Senegal valley (November), and finally Toubacouta in December. Oh and a memorable day trip on a successful quest for the enigmatic Quail-Plover!
Another series focused on recent ornithological publications relevant for Senegal, in three parts. I’m not sure how I managed but in the end I was involved in quite a few articles published in 2019: the autumn migration of seabirds at Ngor and the status of Iberian Chiffchaff in West Africa (the latter with Paul Isenmann and Stuart Sharp) in Alauda, the first records of Eurasian Collared Dove and of Turati’s Boubou in Senegal (the latter with Bruno Bargain) published in Malimbus, and finally two papers in the Bulletin of the African Bird Club: a short piece on the hybrid shrike from lac Tanma in 2017 (with Gabriel Caucanas), and a review of the status of the Short-eared Owl in West Africa, following the influx during winter 2017/18.
Many thanks to all visiting and (semi-)resident birders who shared their observations through eBird or other channels, particularly Miguel, Frédéric and Bruno. The above review is of course incomplete and probably a bit biased towards the Dakar region: any additions are more than welcome and will be incorporated!
Pas trop le temps pour écrire en ce moment (trop d’oiseaux à compter au Calao!) je voulais tout de même partager quelques clichés pris lors d’une nouvelle visite au Bas-Delta du fleuve Sénégal, au tout début du mois. En compagnie, bien sûr, du référent local et fin connaisseur de l’avifaune de la région – que dis-je, de la faune tout court – Frédéric Bacuez. D’abord les environs de Bango et les Trois-Marigots, puis une journée dans le parc national du Djoudj avec Vieux, Miguel et Rosa en plus dans la bande, puis pour terminer une matinée dans la réserve de faune du Ndiael. Pas loin (voire un peu plus) de 200 espèces observées pendant notre long weekend ornitho, tous les détails comme d’hab sur eBird.
Sans plus tarder, voici donc en ordre chronologique une petite série d’images:
Divers articles consacrés à l’avifaune sénégalaise ont été publiés ces dernières années, nous incitant à faire une petite synthèse de ces publications. Le Sénégal est depuis une cinquantaine d’années une terre fertile pour les études ornithologiques, et ces dernières années cela n’a pas changé. Peut-être bien au contraire, même s’il n’y a plus de vrais ornithologues tels que les Morel ou Baillon résidant au pays – peut-être qu’un jour on se risquera à une note sur les nombreux chercheurs et autres personnages ayant marqué l’histoire ornithologique du pays. Peut-être.
Pour le moment, on se limitera aux 3-4 dernières années (2016-2019), en commençant par les publications ayant trait à l’écologie des espèces, suivi par quelques traités taxonomiques pertinents. La deuxième partie couvrira principalement les articles traitant du statut, de la phénologie et de la répartition d’espèces. J’en oublie certainement, donc tout complément que vous pourrez apporter sera grandement apprécié! Une partie des articles qui suivent sont déjà accessibles en ligne, p.ex. sur le site ResearchGate. Quelques-uns se trouvent sur notre page Ressources. Si nécessaire, je peux aussi fournir la plupart sur demande.
Seul bémol, l’absence quasi totale d’auteurs sénégalais dans les publications qui suivent… espérons que la relève ornitho locale – elle existe bel et bien, timidement – pourra changer cet état des lieux dans un futur proche. Ce triste constat a même été démontré, chiffres à l’appui, dans un article récent paru dans la revue Ostrich: Cresswell W. 2018. The continuing lack of ornithological research capacity in almost all of West Africa. Ostrich 89: 123–129. [Le manque continu de capacité de recherche ornithologique dans presque toute l’Afrique de l’Ouest]
- Comment les Busards cendrés font face au Paradoxe de Moreau pendant l’hiver sahélien: Schlaich et al. 2016. How individual Montagu’s Harriers cope with Moreau’s Paradox during the Sahelian winter. Journal of Animal Ecology (doi: 10.1111/1365-2656.12583).
Cette étude sur le Busard cendré, menée par une équipe franco-hollandaise, illustre de manière concrète comment un hivernant paléarctique répond au paradoxe de Moreau. Ce terme fait référence au phénomène des conditions écologiques se dégradant au fur et à mesure que la saison d’hivernage avance dans le Sahel alors que les migrateurs doivent se préparer pour leur migration prénuptiale bien que les conditions soient alors plus sévères. En suivant 36 busards hivernant au Sénégal, l’équipe a étudié leur utilisation de l’habitat et leur comportement tout en collectant des données sur l’abondance des criquets, leur principale source d’alimentation sur les quartiers d’hiver. Ils ont trouvé que la fin de la période d’hivernage pourrait constituer un goulot d’étranglement au cours du cycle annuel, avec des effets de report possibles sur la saison de reproduction. Les changements climatiques en cours avec moins de précipitations dans le Sahel, associés à une pression humaine accrue sur les habitats naturels et agricoles, entraînant dégradation et désertification, rendront probablement cette période plus exigeante, ce qui pourrait avoir un impact négatif sur les populations d’oiseaux hivernant dans le Sahel.
Le Busard cendré est l’une des rares espèces à être bien étudiée au Sénégal, notamment par des chercheurs de l’Université de Groningen (dont Almut Schlaich et Ben Koks) et du CNRS en France (V. Bretagnolle et cie.). La Barge à queue noire et dans une moindre mesure peut-être le Balbuzard pêcheur, deux autres espèces prioritaires pour la conservation en Europe de l’Ouest, sont également relativement bien suivies dans leurs quartiers d’hiver au Sénégal et régions limitrophes.
- Sélection de l’habitat, “home range” et taille de population de la Marouette de Baillon dans le delta du Sénégal: Seifert, Tegetmeyer & Schmitz-Ornés 2017. Habitat selection, home range and population size of Baillon’s Crake Zapornia pusilla in the Senegal Delta, north-west Senegal. Bird Conservation International (doi:10.1017/S0959270917000077).
Les trois chercheuses (équipe 100% féminine, fait assez rare pour le signaler !) se sont penchées sur une espèce très peu connue et difficile à étudier, en utilisant une approche multi-échelle pour évaluer les exigences en matière d’habitat de la Marouette de Baillon dans le delta du fleuve. Elles ont suivi par télémétrie 17 individus dans le PN des Oiseaux du Djoudj, puis ont modélisé à partir d’images satellitaires et des données de capture la probabilité de présence ainsi que la densité de la population. La taille du domaine vital de l’espèce mesure en moyenne 1,77 ± 0,86 ha, avec des différences significatives entre habitats. La Marouette de Baillon préfère au sein de ses habitats les structures de bord, comme les pistes battues, les bords des plans d’eau ouverts, ainsi que les limites d’une végétation spécifique. Basé sur les modèles de régression, 9’516 ha d’habitat favorable ont été identifiés dans la zone Djoudj, avec une taille de population potentielle de 10’714 ind. (3’146-17’408). Les zones humides du delta du fleuve ont donc une importance exceptionnelle pour les populations africaines et peut-être aussi européennes.
La même étude a également permis la publication, en 2015, d’un article sur le régime alimentaire de ce rallidé : Seiffert, Koschkar & Schmitz-Ornés 2015. Diet of Baillon‘s Crakes Zapornia pusilla: assessing differences in prey availability and consumption during the breeding season in the Senegal River Delta, West Africa. Acta Ornithologica 50: 69–84. [Régime alimentaire de la Marouette de Baillon : évaluation des différences en matière de disponibilité des proies et de consommation pendant la saison de reproduction dans le delta du fleuve Sénégal].
- Ecologie de l’alimentation de phaétons se reproduisant dans deux environnements marins contrastés de l’Atlantique tropical: Diop et al. 2018. Foraging ecology of tropicbirds breeding in two contrasting marine environments in the tropical Atlantic. Marine Ecology Progress Series 607: 221–236.
Menée par Ngone Diop, cette étude combine le suivi par GPS, des variables environnementales et des échantillons des régurgitations au cours de l’incubation et de la ponte pour comprendre l’écologie alimentaire du Phaéton à bec rouge, ainsi que les stratégies de recherche de nourriture susceptibles de changer entre deux environnements marins différents: les Iles de la Madeleine (situées dans la remontée du courant canarien) et l’île de Sainte-Hélène au centre de l’Atlantique sud. Des différences substantielles observées dans le comportement d’alimentation entre les deux colonies indiquent qu’il faut être prudent lorsqu’on extrapole les habitudes de recherche de nourriture des oiseaux de mer tropicaux se reproduisant dans des environnements océanographiques contrastés. La surexploitation de petits poissons et du thon peut réduire les possibilités d’alimentation et conduire à une concurrence avec les pêcheries. On incluera le résumé d’une autre publication par Ngoné, celle-ci sur la taille de la population et la phénologie de reproduction de nos chers phaétons du PNIM, dans la 2e partie.
- Distribution spatiale et comportement de nidification de l’Echasse blanche dans la zone humide urbaine du Technopole: Diallo, Ndiaye & Ndiaye 2019. Spatial distribution and nesting behavior of the Black winged-stilt (Himantopus himantopus himantopus, Linnaeus 1758) in the urban wetland of Dakar Technopole (Senegal, West Africa) – J Biol Chem Sciences 13: 34-48.
Cette étude menée par Yvette Diallo de l’UCAD a été conduite en deux temps, d’abord en 2012 puis en 2017, permettant d’établir les effectifs et de décrire quelques éléments de la biologie de reproduction de l’Echasse blanche. Des dénombrements réguliers pendant la saison de reproduction (délimitée de manière un peu trop restreinte par les auteurs, qui n’ont couvert que la période de mai à août et non d’avril à septembre) ont permis d’établir un effectif maximum de 531 ind. en 2012 et 766 en 2017, les effectifs diminuant dès le début des pluies, lorsque les conditions deviennent moins favorables. En 2012, 25 nids sont identifiés, et pas moins de 79 en 2017. Les résultats sont présentés sous forme de plusieurs graphiques, mais leur interprétation est souvent difficile et on pourra regretter que les conclusions ne sont pas toujours très claires (et que cet article a été publié dans un journal plutôt inhabituel!). L’étude a toutefois le mérite d’améliorer nos connaissances de la biologie de cet élégant limicole en Afrique de l’Ouest, dont les données de reproduction dans la région se limitaient jusqu’à récemment à quelques cas au Sénégal et au Ghana.
Et justement, nous avons entamé la rédaction d’une note sur la reproduction de l’espèce au Sénégal et en Gambie, puisqu’une actualisation de nos connaissances est nécessaire en vue des nouvelles données dont nous disposons. Si tout va bien, rendez-vous en 2020 pour la publication.
- Régime alimentaire et aire de nourrissage des Goélands railleurs nichant dans le delta du Saloum: Veen et al. 2019. Diet and foraging range of Slender-billed Gulls Chroicocephalus genei breeding in the Saloum Delta, Senegal. Ardea 107: 33–46.
Peu d’informations sur l’écologie de la population ouest-africaine de ce goéland sont disponibles pour appuyer les actions de conservation. Les auteurs, dont notre ami Wim Mullié – seul ornitho quasi local impliqué dans l’étude – ont analysé le régime alimentaire sur la base des otolithes de poisson dans les pelotes de rejection et les matières fécales collectées à proximité des nids en fin de période d’incubation, entre 2000 et 2015. Les goélands consommaient principalement des poissons des familles Cichlidae (25-93%), Clupeidae (0-54%) et Mugilidae (0-34%). En 2014, trois goélands ont été suivis par GPS en vue d’étudier les déplacements et les zones d’alimentation. Pendant la journée, ils ont passé 27% de leur temps à couver les œufs, 10% ailleurs dans la colonie et 63% à l’extérieur de la colonie lors de déplacements à la recherche de nourriture, qui pour deux oiseaux avait principalement eu lieu dans des lagons bordés de mangroves, des salins, des criques, des rivières et un complexe de rizières abandonnées. Le troisième a exploré presque exclusivement la côte atlantique près d’un village de pêcheurs en Gambie. Le domaine vital et la zone d’alimentation des trois oiseaux mesuraient 2’400 et 1’800 km², respectivement.
On pourrait encore citer d’autres publications ayant trait à l’écologie et en particulier aux stratégies de migration et d’hivernage d’espèces hivernant dans le pays, mais qui ne concernent pas spécifiquement le Sénégal, comme p.ex. Kentie et al. 2017. Does wintering north or south of the Sahara correlate with timing and breeding performance in black-tailed godwits? Ecology and Evolution 7: 2812–2820. [L’hivernage au nord ou au sud du Sahara est-il en corrélation avec la période et la performance de nidification chez la Barge à queue noire ?], ou encore Grecian et al. 2016. Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem. Biol. Lett. 12: 20160024. [Les points chauds à grande diversité d’oiseaux marins sont liés à la productivité océanique dans le Courant des Canaries].
Puis pour terminer cette section, mentionnons encore notre note brève relatant l’observation par mes amis genevois d’un Grébifoulque se nourrissant sur le dos d’un Hippopotame (Zapun et al. 2018. African Finfoot Podica senegalensis feeding on the back of a Hippopotamus. Malimbus 40: 70-71). On y décrit un comportement rarement observé d’un des Grébifoulques présents à Wassadou en février 2018. Nous avons retrouvé deux mentions d’observations similaires sur le fleuve Gambie, ainsi que des données d’Afrique australe et du Congo-Brazzaville (avec le Buffle et le Bongo), mais ce comportement n’avait à notre connaissance jamais encore été documenté sur photo.
Place maintenant à la taxonomie, domaine pointu de l’ornithologie moderne qui grâce aux techniques d’analyse génétique continue de chambouler nos connaissances du domaine – et qu’il importe de ne pas négliger car comme le montre la première étude en particulier, les implications en termes de conservation peuvent être importantes lorsqu’un taxon est élevé au rang d’espèce. A propos, Simon et moi avons résumé les principales changements taxonomiques récents affectant le Sénégal dans cet article publié en début d’année sur ce blog.
- Quand la morphologie ne reflète pas la phylogénie moléculaire : le cas de trois sternes à bec orange: Collinson et al. 2017. When morphology is not reflected by molecular phylogeny: the case of three ‘orange-billed terns’ Thalasseus maximus, Thalasseus bergii and Thalasseus bengalensis (Charadriiformes: Laridae). Biological Journal of the Linnean Society XX: 1–7.
Rédigé par une équipe internationale, cet article établit notamment que la Sterne royale africaine devrait être considérée comme espèce à part entière, et qu’elle est génétiquement plus proche de la Sterne voyageuse que de la Sterne royale américaine. Ayant été élevée au rang d’espèce, il devrait maintenant être plus facile de mettre en place un statut de protection et des mesures de conservation de ce taxon endémique à l’Afrique de l’Ouest, dont les populations sont assez vulnérables puisque concentrées en quelques colonies seulement.
- Révision taxonomique du complexe d’espèces du Drongo de Ludwig avec description d’une nouvelle espèce d’Afrique occidentale: Fuchs et al. Taxonomic revision of the Square-tailed Drongo species complex (Passeriformes: Dicruridae) with description of a new species from western Africa. Zootaxa 4438: 105-127.
Un billet avait déjà été consacré à cette découverte sur ce blog: en effet, les auteurs décrivent une nouvelle espèce de drongo au sein du complexe de Dicrurus ludwigii, en utilisant une combinaison de données biométriques et génétiques. La nouvelle espèce, le Drongo occidental (D. occidentalis) diffère des autres taxons du complexe par un bec significativement plus gros et par une divergence génétique importante (6,7%) du taxon « sœur » D. sharpei. La répartition de la nouvelle espèce couvre les forêts de galerie des côtes de Guinée (et de la Casamance !) jusqu’au fleuve Niger et le Bénoué au Nigéria.
Une autre étude génétique (par les mêmes auteurs pour la plupart) concerne le Drongo brillant: même si des recherches supplémentaires sont requises, ils recommandent la reconnaissance de plusieurs espèces au sein de ce complexe, les drongos brillants du Sahel et des savanes d’Afrique de l’Ouest devenant Dicrurus divaricatus. Fuchs et al. 2018. Habitat-driven diversification, hybridization and cryptic diversity in the Fork-tailed Drongo (Passeriformes: Dicruridae: Dicrurus adsimilis). Zoologica Scripta 2018: 1–19. [Diversification engendrée par l’habitat, hybridation, et diversité cryptique chez le Drongo brillant].
La suite sera pour dans quelques jours !
We’re continuing our little series on the status of some lesser known passerines that spend the winter in Senegal. This time round we’re looking at Iberian Chiffchaff (Pouillot ibérique), yet another drab songbird that can be tricky to identify unless of course it’s singing. We won’t go much into its identification in this post; a lot has been written on the topic, though unfortunately the standard West Africa field guides lack sufficient detail and may oversimplify the matter somewhat. In addition, few if any of the local guides really know how to identify the species in the field, and not all visiting birders pay much attention to these LBJs.
There are a few subtle differences in plumage, but generally it’s not easy to identify these birds on plumage and “jizz” alone.. so maybe it’s useful after all to summarise key characteristics here. Lars Svensson, in what is still one of the main reference papers on Iberian Chiffchaff identification (2001), neatly listed the following field characters in comparison with Common Chiffchaff:
- As a rule, the entire upperparts of ibericus are purer moss green than on Common Chiffchaff, lacking the brown tinge on crown and mantle usually present in collybita in freshly moulted plumage in early autumn a very slight brownish tinge can be found on the greenish upperparts of some Iberian Chiffchaffs
- More tinged yellowish-green on sides of head and neck, and has no buff or brown hues at all, or only very little of it behind the eye and on ear-coverts. The breast is whitish with clear yellow streaking
- Typically, has vivid lemon yellow undertail-coverts, contrasting with a rather whitish centre to the belly
- Supercilium on average more pronounced and more vividly yellow, particularly in front of and above the eye
- On average, the legs are a trifle paler brown on Iberian than on Common Chiffchaff, though many are alike
- Bill is very slightly stronger [though I find this one of very little use in the field!]
Clearly these are mostly subtle differences and when identifying on plumage alone, a combination of characters should typically be used. Confusion with Willow Warbler is not unlikely, even by experienced birders, and I’m assuming that at least some Iberians are noted as Willow Warbler, especially in mid-winter in northern Senegal when Willow Warbler should in fact be rare, as it winters chiefly in the forest zone further south. The longer wings, pale underparts and paler legs can indeed result in striking similarities between Willow and Iberian. A good pointer to separate these two is that the latter typically dips its tail while feeding, whereas Willow, Warbler characteristically flicks its wings while moving its tail sideways.
The two pictures below were taken by Frédéric Bacuez near Saint-Louis, on 18.4.16 (top) and 20.1.13 (bottom), and while it’s probably impossible to be certain, I do tend to believe these are Iberian Chiffchaffs.
The vocalisations on the other hand are far more reliable and are indeed always ideal in order to confirm an Iberian Chiffchaff, particulary the song. While there’s some variation and there may be some “mixed singers”, the difference with Common Chiffchaff is usually obvious (though maybe a bit less so on this one from Wassadou). It’s worthwhile pointing out though that besides the quite distinctive song, a good yet undervalued criterion is the call of the species – see this nice summary on the Turnstones blog (and also Collinson & Melling 2008, who state that the call “in sharp contrast to that of Common Chiffchaff, is downwardly inflected, from 5 to 3 kHz, transcribed as ‘piu’ or ‘peeoo’, perhaps reminiscent of the call of Siskin” – now compare with my recording from Technopole (same bird as in the song recording): I wouldn’t say this sounds like a Siskin – and even less like a Bullfinch! – and at 3.5-6 kHz the frequency is clearly a bit higher as can be seen on the sonogram below (click to enlarge).
Status & Distribution in Senegal
Up to not so long ago, most authors considered Iberian Chiffchaff to be a resident or partial migrant, mostly due to lack of reliable identification criteria at the time. Svensson (again!) provided the most comprehensive overview of our knowledge of the wintering areas in his 2001 paper, concluding that it is “a long-distance migrant which winters primarily in tropical Africa“. This assumption was however based on very few specimens and even fewer reliable field observations. One of these is of a bird “singing like an Iberian Chiffchaff” by Yves Thonnerieux from northern Ghana, and the only two specimens from wintering grounds are from Mali in 1932 (Segou) and 1955 (Bamako); both were found by Svensson in the museum of natural history in Paris (MNHN). A third specimen was collected in January 1955 in Tunisia, suggesting that some birds may winter north of the Sahara; Svensson also showed that the species is present during spring migration in Morocco (at least late March – early April).
With increased “observer awareness” and better reporting systems, recent years have seen a clear increase in field observations from West Africa, described further below. Combined with the absence of any winter records from the Iberian peninsula, I think it’s quite well established now that indeed most if not all Iberian Chiffchaffs winter south of the Sahara.
To further refine its status in West Africa, we turn to our usual suspects: Morel & Morel provide a single record, presumably obtained by themselves, of a singing bird at Richard Toll on 22-24.2.87 (this is probably the unpublished record “from tropical Africa” that Svensson refers to). This can safely be assumed to be the first published record for Senegal; identification was apparently largely based on song since they write that they compared the song with recordings by Claude Chappuis. It’s quite easy to miss out on this observation though, as ibericus (or brehmi as it used to be known) is only referred to in the annex of Les Oiseaux de Sénégambie (1990), as their sighting was obviously too recent to be included in the near-final manuscript of their book. Of course, the species was at the time still considered to be “just” a subspecies of Common Chiffchaff. Rather curiously, the Morels refer to a significant proportion of Scandinavian Common Chiffchaffs (ssp. abietinus) – up to half! – though we now know that these populations tend to winter in eastern Africa, heading in a south-easterly direction in autumn. Could it be that these were actually Iberian Chiffchaff rather than abietinus?
Moving on, Rodwell and colleagues (1996) refer to three records of calling (singing?) birds in the Djoudj NP in Jan 1990, Jan 1991 and Feb 1992. Sauvage & Rodwell (1998) do not provide any additional records: up to the mid-nineties, ibericus was obviously still considered a rare to scarce winter visitor to northern Senegal. More than a decade later, Borrow & Demey still consider the species’ distribution in Senegal as “inadequately known”, and their map only shows the lower Senegal valley.
As is the case with quite a few other little known taxa that were recently elevated to species rank – think Moltoni’s Warbler, Seebohm’s Wheatear, Atlas Flycatcher – these past few years our knowledge has greatly increased, and it is clear that Iberian Chiffchaff is indeed quite frequent in northern Senegal. Recent reports mainly come from the Djoudj NP – obviously a key wintering site, with decent densities – and from around Richard Toll and Saint-Louis (e.g. Bango, Trois-Marigots, Langue de Barbarie, and see picture above). There are however a number of recent records elsewhere that suggest that the species is more widespread: last winter I was lucky to find a singing bird at Technopole which is thought to be the first record from Dakar; there are also a few reports from the Somone lagoon, though not sure that these are reliable (I have suspected the species here before, but never been able to confirm based on call or song). Rather intriguingly, the species was also seen several times along the Gambia river at Wassadou these past two years: first in December 2017, then more than two months later at least one singing bird that we found on 24.2.18, and again this winter (7.1.19). Finally, another singing bird was reported near Kounkane, Velingara, on 28.1.18 (G. Monchaux) – to our knowledge the first record from Casamance. The observations in these southern locations suggest that the species is more widespread and that it can turn up anywhere in Senegal.
In Mauritania, it appears that up to recently the only records were obtained during extensive field work conducted by the Swiss Ornithological Station, with several birds captured both in spring and in autumn 2003 (Isenmann et al. 2010). There are several more recent reports from around Nouakchott mainly, presumably of birds passing through. In addition to the two aforementioned specimens from Mali, the only other record from that country that I’m aware of is of a singing bird that I recorded in a hotel garden in Bamako, where it was singing for at least a week in January 2016. Burkina Faso should also be part of the regular range, though there again there are just a couple of records, most recently a singing bird reported by van den Bergh from the Bängr-Weeogo park in Ouagadougou in December 2011.
The Xeno-canto range map, which is largely based on BirdLife data, is probably the most accurate when it comes to the winter range (though not for the breeding range, the species being absent from most of central and eastern Spain). It should also include all of northern Senegal, or at a minimum, the lower and middle river valley, particularly the Djoudj NP which is omitted from the map below. I’m not sure that the species has been reliably recorded from Gambia even though there are several unverified observations on eBird. Further north, there are several winter records from Western Sahara between early December and early February, mainly at coastal sites (Bergier et al. 2017), suggesting that not all Iberian Chiffchaffs cross the Sahara. Spring migration is noted from mid-February to mid- or end of April.
Iberian Chiffchaff should be present in Senegal and generally throughout its winter quarters from about October to early or mid-April; the earliest observation I could find is one of a bird reported singing east of Richard Toll on 27.10.15. A Danish group reported two birds in Djoudj in early November 2017, but other than that almost all records are from December – February during the peak orni-tourist season.
Paulo Catry and colleagues (including our friends Miguel and Antonio!) showed marked differential distance migration of sexes in chiffchaffs, with females moving further south than males. Their study did not distinguish between Common and Iberian Chiffchaff, but because south of the Sahara (Djoudj mainly), sex-ratios were more male-biased than predicted by a simple latitude model, their findings suggest that among the chiffchaffs wintering in West Africa, a large proportion is composed of Iberian birds, providing further support that these birds are long distance migrants. The ringing data from Djoudj also showed that chiffchaffs display differential timing of spring migration, with males leaving the winter quarters considerably earlier than females [typically, male migrant songbirds arrive a little earlier on the breeding grounds than females, presumably so they can hold and defend a territory by the time the females arrive].
Finishing off with some essential ibericus reading…
- Collinson & Melling, 2008. Identification of vagrant Iberian Chiffchaffs – Pointers, pitfalls and problem birds. British Birds 101.
- Svensson, L. 2001. The correct name of the Iberian Chiffchaff Phylloscopus ibericus Ticehurst 1937, its identification and new evidence of its winter grounds. Bull. B. O. C. 121.
This is the second part of a review of what we know about Seebohm’s Wheatear in Senegal, the first part covering its identification in autumn and winter. As already mentioned in that piece, this species has a pretty restricted range, breeding only in the Middle and High Atlas of Morocco and Algeria, generally above 1500 meters asl. Until fairly recently it was considered more of an altitudinal or short-range migrant, but it’s clear now that it’s actually a medium-range “total” migrant (i.e. all populations tend to migrate away from breeding grounds – not surprising given that much of it is covered in snow during winter!).
The non-breeding range of “Black-throated Wheatear” is given by the Handbook of the Birds of the World Alive as “West Africa (mainly SW Mauritania and Senegal to W Mali, occasionally in S Morocco)”. However, the HBW range map is rather incorrect: all regions of Senegal and Gambia and even Guinea-Bissau are included, although as far as I know the species has never been reported from the latter two countries. The same applies to Guinea and Burkina Faso which are also partly included in the range. Let’s hope that this will get corrected soon – the HBW species page of this newly recognised taxon (formerly considered a subspecies of Northern Wheatear) was only fairly recently published online, and is obviously work in progress.
The winter distribution in Shirhai & Svensson (2018) on the other hand seems more accurate, though perhaps a bit too conservative in that it includes only a very small part of western Mali. Judging by the data available on the Biodiversité Al-Maghrib portal, it’s clear that some birds winter may further to the north, much closer to the breeding grounds. Indeed, there are several observations from southern Morocco and from the Western Sahara from December-February, and it’s easy to imagine that it’s rather beneficial for these birds if they can avoid crossing the Sahara. There are also a few recent records from the Adrar region in Mauritania, e.g. this one and this one by Wim van Zwieten and friends seen at the end of December last year, suggesting that this area may also be part of the species’ winter range.
The Shirihai & Svensson map is most likely largely based on a paper on Seebohm’s Wheatear in West Africa by Förschler and colleagues (2008), which to date gives the most comprehensive overview of our knowledge of its wintering grounds in the Sahel, following field work they undertook in western Niger, Mali and Mauritania combined with a review of published data. They note that “although seebohmi was previously thought to be a resident or only a partial migrant by some authors, it is now considered a true migrant, with the majority of the population leaving Morocco and Algeria in winter. Browne (1982) found a major wintering area, roughly estimated to hold at least 50,000 individuals, in the eastern part of south-west Mauritania […].” They also refer to three more southern records from Djoudj NP (mentioned by Rodwell et al. 1996), and conclude that “the majority of this taxon’s population appears to winter immediately south of the Sahara, in the Sahel zone of southern Mauritania, northern Senegal and north-west Mali between 15–18°N and 09–16°W, although its wintering grounds may range even further east, including parts of central Mali.”
Away from its regular range, there are a few scattered records of Seebohm’s Wheatear in the Mediterranean and one from the Netherlands (April 2017), plus a couple of possible sightings from the UK: Italy (one in April 2014 in Sardinia), Gibraltar, Malta, Tunisia, and several times in the Libyan desert and even once from western Egypt. It’s also on the list of the Canary Islands, and apparently also reported from Cameroon, as per Arnoud B. van den Berg on DutchAvifauna,nl). So it’s definitely a species to have on one’s radar when encountering an unusual wheatear in western and southern Europe; I can imagine that one day a fine male will show up in spring in the Camargue, the Spanish coast or on the Balearic islands – or pretty much anywhere north of its range for that matter.
Status & Distribution in Senegal
In Senegal, in addition to the aforementioned Djoudj records, the species has been reported from the Richard-Toll, Dagana, Podor and Ndioum areas, and at least once from the lower Senegal valley, on 2.3.09 by Frédéric Bacuez, Ornithondar. Of course, Frédéric had already provided a comprehensive overview of the distribution of Seebohm’s Wheatear in Senegal, more precisely in this blog piece from 2016. The Morels mention several spring records (13 March – 14 April) in the middle Senegal valley as far upstream as Salde, plus one from early January 1981 near Richard-Toll seen by Alan Tye. They also report the presence on two occasions some 60 km south-east of Richard-Toll. But that’s about it: not an awful lot of records to go by! It’s quite possible that it may also be found at least occasionally in the Ndiael reserve, around lac de Guiers and into the Ferlo (e.g. Six Forages). These sites are not very often visited by birders or ornithologists, and the recent records that I came across are typically from Richard-Toll and the Podor areas, with the exception of a first-winter male at Saot (ENE of Touba), seen by J-F Blanc in January 2010. No records are known from the Grande Côte, though it’s not impossible of course that the species shows up here at least from time to time.
As can be seen from the map below, northern Senegal is on the southern edge of the species’ winter range, which may explain why most birds seen here appear to be first-winter birds. Adults, and in particularly males, may well winter further north including on the other side of the Sahara as mentioned earlier. Though it’s certainly not rare, the species seems to be nowhere common across its range in Senegal. When we toured the middle valley in January last year, we saw the species in small numbers (1-2 ind. per site) at three different locations: Bokhol, in a sparsely wooded dune depression east of Ndiayene Pendao, and at Gamadji Sare. Some sites such as the Bokhol “fores” appear to be pretty reliable, and a dedicated search would probably reveal other sites where they may be regular and maybe even locally common; in 1973 Seebohm’s Wheatear was said to be “the most common [wheatear] species in winter in the Podor region”, while Sauvage & Rodwell refer to a total of 18 ind. seen at three locations in February 1993 in the Podor atlas square. There may of course be annual variations, possibly depending on any cold spells in north-west Africa, but obviously more data are needed (as usual!).
The majority of sightings are made between December and early March, but this is when most birders visit the country and it’s likely that Seebohm’s is regularly present at least from (mid?) October and up to early April. In Nouakchott, it’s been seen as early as the end of September (see Rob Tovey’s eBird checklist with two pictures of a fresh autumn male), but when I last visited the Podor region in early October 2018 I did not see any birds on the sites that held several wintering individuals back in January, so it seemed that they had not arrived yet at that time.
In short, the main wintering area of Seebohm’s Wheatear lies in Mauritania, northern Senegal and NW Mali, on the edge of the Sahara and in the northern Sahel zone. It is a regular winter visitor to northern Senegal, being scarce locally fairly common along the middle Senegal Valley, from October/November to March or early April.
The main winter range in West Africa should look something like this, though it possibly extends a bit further south in Senegal and further east along the Mauritania-Mali border. And as mentioned already, some birds may winter in southern Morocco and in the adjacent Adrar region of Mauritania, as well as along the coast north of Nouakchott: the below map may well need to be adjusted as such – comment welcome, as usual.
While its habitat in summer essentially corresponds to Alpine meadows with rocks and stone structures, usually devoid of any trees, in winter the species may inhabit light Sudano-Sahelian woodland, at least along the Senegal valley. Elsewhere, particularly further north in Mauritania, it probably occurs mostly in more open habitat. The Bokhol forest just east of Dagana seems to be a reliable place to find Seebohm’s Wheatear: it is comprised of a mix of Acacia, Balanites aegyptiaca and other trees growing on sandy soil with little or no undergrowth. Indeed, most of the winter range of the species is heavily overgrazed anyway, and away from the floodplains there is generally very little vegetation cover… the picture below gives an impression of the the sad state of what remains of northern Senegal’s “forests” – a very liberal concept here at these latitudes.
We’ve also encountered the species on several occasions at Gamadji Sare, where part of the area is also made up of light woodland, not dissimilar to Bokhol, though less mature. Some birds here were seen in more open areas, including right by the bank of the Doué river where this picture was taken:
In much of its range, the species is cohabiting with Northern (ssp. oenanthe and probably also libanotica), ‘Greenland’ (leucorhoa) and Isabelline Wheatear, probably locally also with Black-eared and Desert Wheatears though the latter two species are typically very scarce in Senegal it seems. Heuglin’s Wheatear is also possible in winter in northern Senegal, but it’s much rarer and was added to the national list only recently, following a record in the Djoudj NP in January 2007 (and was found breeding even more recently in the Kédougou region).
A brief etymology¹ of Seebohm’s Wheatear
The HBW Alive lists this taxon as Black-throated Wheatear, another rather boring and unimaginative English name. I’ll stick to Seebohm’s. Alternatively, Atlas Wheatear would be a pretty good one as it nicely highlights the restricted breeding range of the species; this name is already in use in Spanish and German, and no doubt in other languages.
But actually, why Seebohm’s Wheatear? Tim Birkhead – author of (at least) two great books, The Wisdom of Birds and Bird Sense – wrote about Henry (or should it be Harry?) Seebohm, a 19th century British industrial and ornithologist, most famous for his fieldwork in Siberia. Which doesn’t really explain why our wheatear from the Atlas goes by his name… enter Charles Dixon, who formally described the taxon in 1882 based on a specimen from the Algerian Atlas. A contemporary of Seebohm, Dixon collaborated on Henry Seebohm’s British Birds opus, so I think it’s safe to assume that Dixon named his newly described chat in honour of his friend.
The term “wheatear” apparently comes from “white” and “arse”, referring to the prominent white rump found in most species.
¹ Etymology is the study of the origin of words and the way in which their meanings have changed throughout history. Applied to vernacular and scientific bird names, this comes down to retrieving the origins of these names.
Thanks once again to Frédéric Bacuez and Wim van Zwieten, and now also to Jérémy Calvo for making available some of their pictures from Mauritania and Morocco
Last winter, I had the chance to have a closer look at a species that is relatively little-known, particularly on its wintering grounds: Seebohm’s Wheatear, a former subspecies of Northern Wheatear that was fairly recently (though long overdue it seems) recognised as a full species by many authors, though surprisingly not yet by IOC. These neat little birds have a pretty restricted breeding range, only occurring in the Atlas mountains of Morocco and Algeria. A couple of years ago I had the chance of seeing these birds for the first time, more precisely in May on their breeding grounds at Oukaimeden, birding hotspot incontournable of the Moroccan High Atlas. As such it was particularly nice to meet up with them on their Sahelian wintering grounds a few months later, during our memorable trip up north in January 2018.
Wheatears can be tricky birds to identify, with several species often posing a bit of an ID challenge, and Seebohm’s is no exception. However, nothing much has been written about the identification of first-winters and adults in non-breeding plumage¹, and depictions in standard field guides may be misleading or even incorrect. In an effort to further our knowledge of the species, we thought it may be useful to summarise what we know based on our limited experience with Oenanthe seebohmi in the field here in Senegal, combined with a brief study of available pictures. Note though that by no means is what follows necessarily a comprehensive overview; additions and corrections are most welcome as usual.
A second blog post will focus on the status & distribution of the species.
Identification in winter
While straightforward to recognise in spring, Seebohm’s Wheatear on its Sahelian wintering grounds can be difficult to identify, mainly because they may superficially resemble Desert or Black-eared Wheatear, while young birds and some females may look like Northern Wheatear. We’ll start by reviewing field characters as found in the most relevant literature: mainly the excellent Robins and Chats (Clement & Rose 2015), Nils van Duivendijk’s Advanced Bird ID Guide (2010), and the recently published seminal reference guide by Shirihai & Svensson (Handbook of Western Palearctic Birds: Passerines, 2018). Let’s see how these can be applied to some of the pictures of presumed Seebohm’s taken in winter.
- Size & overall impression are very similar to Northern Wheatear, though it is slightly smaller than that species – something that’s not necessarily obvious in the field unless maybe in direct comparison to nominate Northern; it’s clear though that Seebohm’s definitely doesn’t look larger than Northern as is the case with ‘Greenland Wheatear’ (= ssp. leucorhoa) where the size difference is usually obvious in the field.
- Structure is typical of wheatears and does not appear to be very different from Northern either; the wing is supposedly slightly shorter, though this is not really obvious in the field, several of the pictures presented here actually show rather slender long-winged birds with an important primary projection, rarely giving a more compact appearance. On most pictures presented here we can however verify that the primary projection is slightly less than the length of exposed tertials (Shirihai & Svensson).
- The bill and tail are said to be “rather longer” than Northern, but these differences are again likely of little use in the field, and I’d imagine that there’s some overlap between species – more measurements on museum skins are likely needed to confirm this.
- In all plumages, the black terminal tail band is narrower than in Northern Wheatear (on outer tail feather, ca. one third of the length of the feather is black), though yet again this is not a very useful field character unless good pictures of the tail are obtained.
- Another key difference is that the underwing coverts are entirely black in males, while in females there are pale streaks on dark underwing coverts, unlike in Northern.
Adult and second-year males are generally straightforward to identify in autumn and winter, when they largely retain their distinctive head pattern, only to a limited degree obscured by pale fringes, combined with very pale underparts and “largely greyish or slighly sandy-grey” upperparts. As a result, adult males should be easy to pick out in autumn and winter, despite not showing the crisp black/grey/white plumage typical of spring males. Still, they remain very distinctive and are unlikely to be confused with any other species, such as this one from the end of March on wintering grounds in southern Mauritania, photographed by the late Robert Tovey (Birding for a lark blog):
The two birds below were photographed in Nouakchott by Rob Tovey, at the end of September and mid-October, respectively. Both are clearly males, and while not very grey, I believe both are 1st year birds (note moult limit on first bird). However, ageing of these birds “requires close inspection of moult and feather wear and pattern in wing” (Shirihai & Svensson) and is often not straightforward – more on this below. This bird on Afbid from January near Richard-Toll, photographed by Nik Borrow, clearly shows an adult-type male, with a largely grey crown, mantle and scapulars.
There appears to be some confusion about the plumage of adult females in the literature, with some authors only mentioning that adult females have a “(dark) grey mottled throat” (van Duivendijk), whereas Svensson in the Collins Bird Guide writes that “females and imm. are often inseparable from [Northern] Wheatear unless showing hint of mottled grey throat (rare though)”. Clement & Rose provide illustrations of an adult male and a dark-throated adult female, but don’t bother illustrating typical females, nor do they show any birds in autumn and winter. They do note that females are variable, ranging from closely resembling typical females of Northern Wheatear, to showing brown ear-coverts and having black or blackish-brown lores to chin and throat tipped with buff, grey or sandy colour – thus more resembling the males in head pattern. Not very clear!
Luckily, Shirihai & Svensson are more precise, stating that adult females are “almost identical to ad. f. (and young m.) libanotica Northern Wheatear, and contrary to previous descriptions nearly always lacks dark bib.” Black- or grey-throated females are thus considered rare. They go on to describe the upperparts as “largely pale grey (with limited sandy-brown suffusion) including on crown. Usually has duskier or almost blackish lores and ear-coverts; whitish supercilium often narrow and short, hardly extending to forehead […].”
Here’s a typical female in spring on the breeding grounds at Oukaimeden, and this picture on Afbid is from May at Ifrane. Adult females in autumn are said to be much as in spring but warmer.
The ageing criteria for first-winter birds, according to van Duivendijk, are as in Pied Wheatear [everyone knows these criteria by heart, right?!]: primary coverts with slightly frayed broad white fringes (ad autumn: often narrower and sharply bordered); primaries brown to brown-black often with pointed and worn tips; pale fringes to secondaries complete and cream-coloured; sometimes moult limit visible in greater coverts. There you go, just in case you’d forgotten. Ageing is thus largely based on moult limits, with first winter birds retaining juvenile primaries, primary-coverts and outer greater coverts, whereas in adults these are evenly fresh.
Back to Shirihai & Svensson, who state that first-winter males are “more female-like and rather feature-less, but still approaches fresh ad. m., having greyer upperparts and darker face with exposed black mottling especially on sides and lower throat; warmer below (Variation poorly known and requires more study)”, and that first-winter females have the “least contrasting plumage, with paler face pattern, and browner/duller ear-coverts.”
Let’s put the above to the test on some of our pictures from Senegal!
The following four photographs show three different birds from January; all are presumed to be first-winter males with varying levels of black extent on the face and throat. I initially assumed these to be adult males, but judging by the description of non-breeding males (by Shirihai & Svensson mainly) and compared to some of the pictures presented earlier on and those in Förschler et al., I now tend to label them as first-winter birds – mainly because of the overall sandy-coloured upperparts, mostly lacking grey tones. Again, keep in mind that ageing of these birds can be tricky and is not always possible! In the first bird, note the largely black throat and face appearing rather “smudged”, a fairly large white front merging into a clear whitish eyebrow extending well beyond the eye, and largely pale sand-coloured mantle and scapulars, the latter with a hint of light grey. The wings in the bird below appear relatively contrasted black and white, with extensive white fringes to the secondaries.
In this picture of the same bird, the greyish scapulars and some grey mottling on the back are more apparent:
This one taken earlier that same day in a different location shows a bird with less white on the chin and gives a very “cold” impression, though this is certainly exaggerated by the subdued early morning light. See also this picture of the same bird, as well as the second picture in this post (the one with spread out wings) which may well show the same bird, five weeks later in the same spot. Not sure about sex here – probably a male, but we probably can’t exclude a dark-throated female.
The same goes for this one from last December, taken by Wim van Zwieten near Podor. This bird also has fairly little black on the face but extensive pale fringes to greater and primary coverts as well as to secondaries, suggesting a first-winter male, though again not sure it can safely be sexed. These birds may be mistaken for Desert or Black-eared Wheatear (the black-throated form of which sometimes occurs in Senegal, though it’s probably rare), even by experienced birders.
The next bird gives a very pale impression, with uniform light sandy upperparts and a white lower breast, flanks, belly and vent. The upper breast are warmer tinged with a buffish wash extending down from the ear coverts, and so are the undertail coverts. The black or dark brown loral stripe is reminiscent of Isabelline Wheatear, but it has a narrow yet distinct supercilium both in front and behind the eye and has a different ‘jizz” and wing pattern than Isabelline. I’ve concluded that it’s a first-winter female, but as always would stand happy to be corrected. Either way, the very white underparts and pale upperparts stand out and should immediately point to Seebohm’s.
Of course, identifying a female or 1st winter bird in a vagrant context is something else. While not necessarily impossible, it will require a combination of characters as well as proper photographic documentation of underwing and tail pattern in particular. There have been at least two suspected birds in autumn in the UK but which could not be confirmed as definite Seebohm’s (read up more on these tricky birds here on Birding Frontiers). The first confirmed sighting for NW Europe was of a male in May 2017 in the Netherlands, a typical case of “overshooting” by North African or Mediterranean species during spring migration. Elsewhere in Europe, the species has been reported as a vagrant from Gibraltar, Italy, Malta, the Canary Islands.
Stay tuned for part II!
– Bram, with thanks to Frédéric, Simon, and to Wim for the use of his picture. And most importantly, a posthumous tribute to Robert Tovey who in a short few years made valuable contributions to our knowledge of birds in Mauritania, before unexpectedly passing away in September last year.
¹ Note (19.2.19): The only exception is actually a remarkable paper written by Mayaud in… 1951, in the French journal Alauda (19:88-96): Le plumage prénuptial d’Oenanthe oenanthe seebohmi (Dixon), in which the author provides a detailed description of birds in non-breeding plumage.
(continued from our first blog post on this road trip)
After leaving Gamadji Sare behind, we made our way towards Podor with a few stops en route. A nightjar sheltering from the heat (and predators) was flushed by Vieux near forêt de Golette, just minutes after he casually mentioned that those bushes look good for nightjars! We were hoping for one of the rarer species of course, but it turned out to be a Long–tailed Nightjar after all, apparently a (young?) bird in very fresh plumage. Also several Knob-billed Ducks here, a Short-toed Eagle, Spotted Thick-knee, Vieillot’s Barbet and so on.
At the scenic Podor quay we had a Marsh Harrier, at least two House Martins and several Red-chested Swallows, some of which were on the opposite side of the river, meaning these were in Mauritanian territory: not insignificant since apparently there aren’t any solid records from our northern neighbour, despite the fact that the species surely must breed on the Mauritanian side of the Senegal delta. Just like in January, we also saw the species further downstream at Dagana. A Montagu’s Harrier and a Black Kite were seen just south of town.
Continuing our westbound journey, we cris-crossed the rice paddies with a few quick stops en route, including an emergency stop near Fanaye Dieri for a raptor which initially puzzled us both, and which turned out to be a young Beaudouin’s Snake-Eagle. This seems to be a (very) scarce wet season visitor to northern Senegal and to southern Mauritania where breeding has been confirmed.
At Dagana, the main feature was the constant stream of herons and Long-tailed Cormorants en route to their nigh roost (or in case of the Black-crowned Night-Herons, en route to their nightly feeding grounds). The roost is located in the swamps just east of Dagana, and hosts what must be several thousands of birds. Three Glossy Ibises flew into Mauritania, while Greater Swamp Warblers were singing on the northern river bank. An evening walk produced Nightingale, Barn Owl, Long-tailed Nightjar and more.
Day 4: Big Day! Dagana to Saint-Louis via Richard Toll and the lower delta
October 6 happened to be the first “October Big Day” organised by Cornell – more on this eBird page.
Pre-breakfast birding at Bokhol “forest”, then from Dagana to Richard Toll with a couple of stops en route and a visit to the sand quarry where I wanted to check on the Blue-cheeked Bee-eater colony: with some 500 nest holes, probably at least half being active nests, this is an impressive sight. Bonus species here were Northern Anteater Chat, Cricket Warbler, and especially two Standard-winged Nightjars flushed from “broom bushes” which were a real surprise here (but once again both were female type… so alas no standards!). The picture of the quarry shows the habitat of the latter two species in the background. Along the track into the sugar cane plantations, more White-throated Bee-eaters, both bishops, Black-rumped Waxbills, and a fine Pin-tailed Whydah.
But we’re getting ahead of ourselves… at Bokhol, the fields were rather quiet and unlike in Gamadji Sare the previous morning we barely had any northern songbirds. The forest held goodies such as Senegal Batis, more Orphean Warblers, Fork-tailed Drongo, Brubru, a Red-necked Falcon with prey, and a much less expected Klaas’s Cuckoo singing in the distance (appears to be a rare breeder during the wet season in northern Senegal). Full species list here. Another Whinchat and a few other migrants were seen just west of Dagana.
Negotiating our way out of Richard Toll, we continued on to Ross Bethio, more specifically the ponds along the track to the Djoudj NP. This is where Vieux found a Lesser Jacana back in July: only the fifth record for the country (and second in the north), this was an exciting find of course, further highlighting the potential of this site which has received little attention from birders let alone from the National Park authorities – though the good news is that from this year on, the site is included in the monthly waterbird counts conducted by the Djoudj park staff. Full story on the jacana record on Ornithondar, merci Frédéric. During our visit there were loads of herons and whistling ducks, pelicans, several Black Storks and Yellow-billed Storks, more Eurasian Coots, etc. More unusually, we spotted several Marbled Ducks, counting at least 11 of these cool ducks. This appears to be an early date, and a rare record outside the nearby Djoudj NP: almost all observations tend to be from the same area in the national park, at the Grand Lac, typically between December and February. We’d already seen Little Grebes, but now Vieux also spotted a Black-necked Grebe, an adult coming out of its breeding plumage. Again an early date of an uncommon species in Senegal, typically seen in mid-winter in the north. All in all some 78 species were seen here, see eBird checklist.
The long drive through the delta along the Djoudj track was pretty uneventful, and we only stopped briefly at Saint-Louis to watch a group of Black-tailed Godwits which unfortunately were feeding knee-deep in the lagoon, so no colour-rings could be seen. The Saint-Louis sewage works are always a hit, but too often they are ignored by visiting and local birders alike: I was thus keen to show Vieux this site even if we had just about half an hour left. As always, plenty of birds here, best of all being a Great Reed Warbler. We said our goodbyes here, and I continued onto Zebrabar where I’d spend the night, picking up several wader species new for the trip list as well as Brown Babbler on the camp grounds.
Day 5: final bit of birding at Langue de Barbarie et Guembeul lagoons
Up before dawn, I first went to the floodplain south of Guembeul: Savile’s Bustards singing in all directions, a flock of spoonbills of both species frantically feeding, and a good mix of warblers (Melodious, Subalpine, Bonelli’s, Common Whitethroat). The lagoons held Avocets, Black-tailed Godwits (including a ringed bird from northern Germany), lots of Little Stints, Dunlins, Curlew Sandpipers, and so on. A Pallid Swift was seen near Guembeul, and the lagoons near the STEP held a handful of Shovelers and White-faced Whistling-Ducks, including a family with some 11 ducklings, with Little Grebes also showing signs of local breeding.
Time to head back home… uneventful drive, with just a few quick stops between Mouit and Louga whenever I encountered vultures such as this one: