Lots going on at Technopole at the moment, and hardly any time to write… pretty much as usual.
So here’s a quick update and a few pics, starting with some of the highlights:
- The two obliging Buff-breasted Sandpipers are still present, seen each time in the area behind the fishermen’s cabin. The country’s 7th or 8th record, and also by far the longest staying birds.
- This may be getting boring now and a bit of a déjà-vu, but yet again a Lesser Yellowlegs showed up in Dakar. This one was photographed on 8/2/18 by J. Dupuy and posted on observation.org; as far as I know this is the 8th record for Senegal and the third for Technopole (after singles in August 2015 and January 2016). Yesterday morning, a visit with French birders Gabriel and Etienne allowed us to relocate the bird, a very nice adult coming into breeding plumage:
- Almost just as good, and another first for Technopole (232 species on the list now), was this Common Shelduck – not totally unexpected given the small influx that took place this winter, but still a very good record and always nice to see this pretty duck showing up on my local patch. Unlike its name suggests, it’s definitely not common in Senegal, as there appear to be only about nine previous (published) records, two of which were also obtained this winter.
- Along the same lines, another scarce species showed up at Technopole recently, possibly still the same as the one I saw at the end of December: a Jack Snipe on 12 & 19/2. Only a few Garganeys are present at the moment, but Northern Shovelers are still numerous these days. At east three Eurasian Teal were with the preceding species (two males on 27/10, and a pair on 10/2).
- Remember that influx of Short-eared Owls? Well it looks like it’s not finished yet, with the discovery of no less than seven (maybe even more!) Short-eared Owls roosting together, on 3/2, by Edgar and Jenny Ruiz (at least two birds were still in the same place on 18/2).
Switching categories now – ring reading! Even with such a diversity and sheer numbers of ducks, waders, terns, gulls to go through, we’re still paying attention to ringed birds. And making very modest contributions to our knowledge of migration strategies, survival rates, and much more – one bird at a time. Since the start of the year we’ve been able to read about 50 rings of more than 40 different birds, mostly Audouin’s, Lesser Black-backed and Slender-billed Gulls, but also a few more original species:
- The flock of 170-180 Avocets that are still present contains at least two colour-ringed birds, both from SW Spain where they were ringed as chicks in… 2005! That’s nearly 13 years for both birds – a respectable age, though it seems that this species can live way longer that that: the record for a British (& Irish) Avocet is nearly 24 years (impressive… though not quite as much as a that 40-year old Oystercatcher!). Interestingly, “RV2” had already been seen at Technopole five years ago, by Simon, but no other sightings are known for this bird.
- A few Black-tailed Godwits are still around though the majority has now moved on to the Iberian Peninsula from where they will continue to their breeding grounds in NW Europe. Reading rings has been difficult recently as birds tend to either feed in deeper water, or are simply too far to be read. This one below is “G2GCCP”, a first-winter bird that hatched last spring in The Netherlands and which will likely spend its first summer here in West Africa. Note the overall pale plumage and plain underparts compared to the adult bird in the front, which has already started moulting into breeding plumage.
- Mediterranean Gulls are again relatively numerous this winter, with some 8-10 birds so far. As reported earlier, one bird was ringed: Green RV2L seen on 21 & 27/1, apparently the first French Med Gull to be recovered in Senegal.
- The Caspian Tern “Yellow AV7” is probably a bird born in the Saloum delta in 2015 – awaiting details.
- The regular Gull-billed Tern U83, ringed as a chick in 2009 in Cadiz province, seems to be pretty faithful to Technopole: after four sightings last winter, it’s again seen on most visits since the end of January.
A morning out to Lac Rose on 11/2 with visiting friends Cyril and Gottlieb was as always enjoyable, with lots of good birds around:
- The first Temminck’s Courser of the morning was a bird flying over quite high, uttering its typical nasal trumpeting call. The next four were found a little further along, while yet another four birds were flushed almost from under the car, allowing for a few decent pictures:
- The now expected Greater Short-toed Larks were not as numerous as last year, with a few dozen birds seen, sometimes side by side with Tawny Pipit. No Isabelline nor any Black-eared Wheatears this time round, but one of the Northern Wheatears was a real good fit for the leucorrhoa race from Greenland (& nearby Canada and Iceland).
- As usual, a few Singing Bush Larks were about, though not very active and as always quite difficult to get good views of as they often remain close to cover, even sheltering under bushes.
- Quite surprisingly, we saw lone Sand Martins (twice), a House Martin, and especially Red-rumped Swallow – the latter a long-awaited addition to my Senegal list. Already on the move, or are these hirundines overwintering in the area?
- A final stop on the edge of the plain, where the steppe transitions into the dunes on one side and a seasonal pond (now dry) on the other. Here we found a couple of species that I’d seen in the same spot before, particularly two that have a pretty localised distribution in western Senegal it seems: Yellow-fronted Canary, and Splendid Sunbird. Also seen here were another Red-necked Falcon, Mottled Spinetail, Vieillot’s Barbet, etc.
- And plenty of gulls by the lake! First time I see this many gulls here, with at least 800 birds, mainly Audouin’s (ca. 350) and some 500 Lesser Black-backed Gulls. Lots of ringed birds of course, but most were too far and we didn’t take the time to go through the entire flock.
And elsewhere in Dakar…
- A “Pallid Heron” Ardea (cinerea) monicae was found by Gottlieb and Cyril at Parc de Hann on 13/2 (but not relocated yesterday…). A rare Dakar record!
- Seawatch sessions at Ngor continue to deliver good species, most notably good views of several European Storm-Petrels these past couple of weeks. Lots have been seen along the Petite Cote (Saly, Somone, Toubab Dialaw) recently, and especially at the Gambia river mouth where several dozen birds were counted.
Visite de routine du dimanche matin au Technopole, avant-hier avec Miguel.
Tout comme ces dernières semaines, il y a plein de monde sur notre hotspot urbain favori: très nombreux limicoles profitant des conditions de nourrissage idéales en ce moment, plusieurs centaines de canards dans la partie la plus profonde du plan d’eau central, un groupe de flamants, spatules, des pélicans des deux espèces, des centaines de laridés, etc. etc.
Janvier, c’est le mois du comptage international des oiseaux d’eau Wetlands, donc on s’est dits que ce serait intéressant de faire un décompte aussi complet que possible. Pas facile! Il y a des groupes d’oiseaux dans tous les sens, pour certains en partie cachés par la végétation et les îlots, et de surcroît tout ce monde bouge en continu, dérangés à tour de rôle par des rapaces (notamment un Busard des roseaux et un Faucon crécerelle), chiens et pêcheurs. On prend chacun quelques espèces ou on se partage la zone en secteurs afin de faciliter le dénombrement, qui nous occupera bien pendant plus de trois heures.
On commence par les plus faciles: cinquante-cinq Pélicans gris, trente-deux blancs (Great White & Pink-backed Pelican), dix-neuf Spatules blanches (Eurasian Spoonbill), cinq Bihoreaux (Black-crowned Night-Heron), puis juste à côté au pied des palétuviers une Foulque (! Eurasian Coot), douze Flamants,… Les limis ensuite, avec l’Echasse blanche (Black-winged Stilt) en tête: 1’420 individus! J’avais estimé leur nombre à la louche, lors de mes précédentes visites, à 700-900 Echasses, mais n’avais jamais pris le temps de faire une comptage proprement dit. Effectif impressionnant!! Sur la photo ci-dessous il y en a à peu près 200…
Toujours beaucoup de Pluviers argentés (min. 49) et d’Avocettes (107); au moins 18 Gavelots pâtres, 6-7 Petits Gravelots et 665 (!) Grands Gravelots. (Grey Plover, Avocet, Kittlitz’s, Little Ringed & Common Ringed Plover)
Environ 300 Barges à queue noire (Black-tailed Godwit), apparemment en légère augmentation par rapport au début du mois, avec plusieurs individus qui commencent à arborer leur livrée nuptiale. Pas moins de 830 Combattants variés (Ruff)… puis là tout d’un coup, devant nous, deux délicats limicoles surgissent de nulle part: des Bécasseaux roussets! (Buff-breasted Sandpiper!)
Ils se laisseront bien observer même si leur comportement nerveux fait qu’ils sont difficiles à suivre et à photographier, courant rapidement sur la vase sans jamais s’arrêter. Ils se nourrissaient essentiellement sur la vase sèche en bordure des ilots enherbés, un peu derrière la cabane des pêcheurs. Nos deux yankees disparaissent aussi subitement qu’ils ne sont apparus, pour revenir d’un coup au même endroit un peu plus tard. Je suis d’ailleurs persuadé que lors de ma précédente visite j’ai vu passer un de ces oiseaux en vol: ne l’ayant vu que brièvement et l’oiseau ayant disparu loin au fond, je n’ai pas osé l’annoncer comme tel… donc j’étais bien content de pouvoir confirmer!
C’est la septième ou huitième donnée pour le pays, selon si on considère l’oiseau vu en janvier dernier au Lac Rose comme nouvel arrivant ou bien comme l’un des trois individus trouvés en décembre 2017. Petit résumé des précédentes observations ici.
On continue le comptage avec les bécasseaux: 75 Cocorlis, au moins 242 Minutes (sans doute bien plus!), et un minimum de huit Variables, une douzaine de Sanderlings, et enfin six Maubèches. Chez les chevaliers, le Sylvain est le plus nombreux (+40), suivi par les Aboyeurs, Stagnatiles, Gambettes, Guignettes et l’habituel Culblanc (ce dernier dans le même coin qu’une Rhynchée peinte, déjà vue la semaine précédente). (Curlew Sandpiper, Little Stint, Dunlin, Sanderling, Knot, Wood Sandpiper, Greenshank, Marsh Sandpiper, Redshank, Common Sandpiper, Green Sandpiper, Greater Painted-Snipe)
Maintenant au tour des mouettes, goélands et sternes – douze espèces en tout, essentiellement des Goélands railleurs (450) et bruns (près de 200; Slender-billed & Lesser Black-backed Gull). Avec comme souvent quelques trucs plus rares dans le tas: un Goéland leucophée (Yellow-legged Gull) adulte, quatre ou cinq Mouettes mélanocéphales (Mediterranean Gull), tous de premier hiver, dont un oiseau porte une bague verte avec inscription blanche! On arrive tout juste à la déchiffrer, RV2L. Cet oiseau bagué en tant que poussin en juillet 2017 sur l’ile de Noirmoutier (Vendée, France) fournirait du coup la première reprise de bague pour l’espèce au Sénégal. Un autre oiseau français avait déjà été contrôlé en Gambie en mars 2015, mais pour le reste il n’y a apparemment pas de reprises de Mouettes mélanocéphales en Afrique de l’Ouest. On est ici vraiment en limite de l’aire d’hivernage régulier donc très peu d’oiseaux sont vus au Sénégal, pour la plupart des individus dans leur premier hiver en région dakaroise. Cette espèce coloniale très étudiée en Europe – un peu comme les Goélands d’Audouin du bassin méditerranéen – cela devait arriver tôt ou tard qu’un oiseau bagué pointe le bout du bec chez nous.
On arrivera également à déchiffrer les bagues de deux Goélands railleurs, un Goéland d’Audouin, une Sterne hansel (U83, déjà vu l’hiver dernier) – tous espagnols – et une Barge à queue noire hollandaise. (colour-ringed Slender-billed & Audouin’s Gulls, Gull-billed Tern, Black-tailed Godwit)
Ensuite les canards, d’habitude faciles à compter au Technopole car ils sont rarement présents en nombre. Cette saison c’est différent: depuis octobre, on voit plus de Sarcelles d’été (Garganey) que ces dernières années, et depuis le début du mois il y a une quantité inhabituelle de Canards souchets (Northern Shoveler). En effet, on arrive à environ 420 souchets et 110 sarcelles – là aussi, de beaux effectifs pour le site! A mettre en relation avec le manque d’eau sur d’autres zones? J’allais presque oublier les Grèbes castagneux (Little Grebe), pour lesquels on fait encore péter le score: pas moins (et en fait plutôt plus) de 527 individus.
Apres tout cela, on en a enfin terminé avec les oiseaux d’eau, pour un bilan de plus de 6’000 individus de 61 espèces différentes. Qui dit mieux?
En plus des passereaux hivernants classiques – Bergeronnettes printanières, Pouillots véloces, Fauvettes passerinettes, Phragmites des joncs – il y avait ce matin aussi un Traquet motteux. (Yellow Wagtail, Common Chiffchaff, Western Subalpine Warbler, Sedge Warbler, Northern Wheatear)
Sinon bonne présence de l’Hirondelles de Guinée, avec une troupe considérable (+38!) qui évoluent au-dessus de la zone, et dont plusieurs individus semblent collecter de la boue pour le nid. Aussi quatre Toureterelles masquées, quelques Martinet des palmes et une petite troupe d’Erémomèles a dos vert, trois espèces assez rarement vues au Technopole. (Red-chested Swallow, Namaqua Dove, Palm Swift, Senegal Eremomela)
Terminons enfin avec une espèce très commune et généralement ignorée par les ornithos (moi en premier), alors qu’elle fait partie d’une des famille d’oiseaux les plus remarquables de la planète: les corvidés. Extrêmement intelligents, ces oiseaux sont connus pour leur esprit curieux, joueur et inventif – au point où il y a des espèces, comme le Corbeau calédonien qui détiendrait la palme des oiseaux les plus smart, fournissant l’un des très rares exemples d’animaux sachant fabriquer et utiliser des outils (avec des modeles variables d’une région à une autre! Et qui disait que “Culture” était un trait purement humain?). A ce sujet, je vous recommande vivement l’excellent The Genius of Birds par Jennifer Ackerman. Mais je divague… là, on observe le manège de deux Corbeaux pies posés non loin et qui semblent s’intéresser de près à un bout de plastique (?). Simple curiosité, envie de jouer, ou intérêt purement culinaire?
It’s about time we reported some news from Gambia on this blog.
Clive Barlow’s recent appointment as official bird recorder for The Gambia is a great excuse to do so. Given its peculiar enclaved geography – just like my home country, a bit of an accident of history, Gambia has always had close ties to Big Brother Senegal, in many ways – cultural, religious, linguistic, ethnic, economic… In the same way, Senegal’s and Gambia’s wildlife and ecosystems are of course intricately connected. A key difference, however, is that despite it being just about 6% of the size of its neighbour, The Gambia has a much higher density of resident birders, birding tours, and local guides, and as such is far better covered, ornithologically speaking, than Senegal.
Want some examples to illustrate the connections between the two? Here’s a first one: the wanderings of Abuko, one of several Gambian “Hoodies” that are equipped with satellite tracking devices. As a youngster, this particular Hooded Vulture was a keen traveler, having covered a good deal of central Senegal, Western Casamance (where it seemingly has taken up residence), and upriver Gambia. The map below shows its movements for the past 4 years.
Another example are the Slender-billed Gulls, Caspian Terns, and Royal Terns that breed in Senegal’s Saloum delta, many of which make it to The Gambia at some point. Take for instance Slender-billed Gull “POL” ringed as a chick in June 2014 at the Ile aux Oiseaux, and seen at Tanji Bird Reserve on 16/3/15, 14/4/15 and again the following winter, on 5/2/16. Among the 40+ other recoveries of the Saloum’s breeders in TG, another one is AUF: ringed on 15/6/15 at Jakonsa (also in the PNDS), it was seen on 26/8/15 at Tanji, and then almost a year later, on 26/6/16, at our very own Technopole.
And now for the very official announcement of Clive’s appointment, by the West African Bird Study Association from Gambia (WABSA):
“As from 15 Oct 2017 WABSA is pleased to appoint Clive R Barlow as the voluntary Country Recorder for bird observations in The Gambia. WABSA intends an annual Gambia bird report & general update of activities for presentation to DPWM & this publication will then will be accessible to all resident ornithologists & visiting birders. The work will also compliment the GIS bio diversity project currently under planning at DPWM. More news of e.g. single species enquiries, colour ring reports, nest/breeding records, will be notified as the project develops. In the meantime various report forms are being developed but feel welcome to email your ad hoc records, trip reports etc past, present & future to CliveRB [email]. Additionally, all related field research activities will involve WABSA and DPWM staff also to partake voluntarily in the absence or presence of funding. ”
So, if you visit TG: please send your records, whether of common birds or rarities, to Clive.
Clive also runs a project on the phenology of Paleartic passerine migrants to The Gambia, running from as far back as 1965 to present, systematically recording the first arrival and last departure dates in the coastal area (Banjul – Tujering). In 2017, we have for instance the last record of Western Olivaceous Warbler in 29/03, with the first return bird as early as 28/07, while Subalpine Warbler was last seen on 26/04 and had a first returning bird on 06/10; Common Swift 14/04 & 30/07, etc. The first Common Nightingale of the autumn was heard singing on 13/11.
Watch this space for more trans-border collaborations and publications! (next up: Great Shearwater in Senegambia, status of Kelp Gull, and more!).
And meet CrB in real life 😉
For now, I’m off to the Djoudj, Langue de Barbarie, Lompoul and Somone. Happy holidays!
(Featured image: “Beach Boys” by CrB, 2017)
(in case you missed the first part, you may want to read this post first)
Thanks to the important research and conservation efforts targeting Audouin’s Gull, a substantial proportion of the population carry colour-rings, to the extent that in any given group one encounters here in Senegal (and elsewhere of course), there are bound to be some ringed birds, usually up to around 15% of all birds. As far as I know this is far more than for any other species that spends the winter here in Senegal; only Black-tailed Godwit comes close (often 5-10%) and maybe Osprey. For instance at Palmarin last month I managed to read 32 rings out of a total of ca. 400 birds, out of which some 200-250 were either close enough to read rings, or were standing (rather than sitting, in which case rings aren’t visible). That’s roughly 13 to 16% of individuals carrying coded rings!
The first mention that I found of a colour-ring recovery is from Delaporte & Dubois (1990) who on 26/1/88 at Saint-Louis observed a bird ringed as a chick in spring 1981 on the Chafarinas islands. Del Nevo and colleagues also noted that many of the birds they counted were ringed, e.g. on 30/9/92, no less than 24 (14%) of 167 birds were ringed: 18 had a darvic [=plastic ring with alphanumerical code] and six had a metal ring only. In 1994 in Palmarin, a Scandinavian team were able to read 16 colour-ringed birds from Spain (out of at least 456; Bengtsson 1994), while Sauvage & Rodwell mention nine colour-ringed birds originating from Spain, in Saint-Louis. The Dutch 1997 expedition managed to read nine rings, out of the 858 gulls that they counted, noting that “these birds presumably all originated from the Ebro Delta, Spain” (and certainly not from the Canary Islands as stated by Triplet 2014! The species doesn’t even breed there… not sure where this error originated).
The rings (or “bands” for our American friends) are either white with a black inscription (3 or 4 alphanumerical characters), or blue with a white 4 character code, and can often be read with a telescope or a good camera. White rings are used in Spain (starting with letters A, B, C or a number) and Italy (I or K), while blue rings are in use in Portugal (with first character P). French birds have a combination starting with F (since 2013; prior to this Italian rings were used); Moroccan ones with M. The images below show an Italian and two Spanish birds (“BDCT” appears twice, photographed in Aug. 2016 and Sept. 2017).
Origin of wintering birds in Senegal
I now have close to 50 ring “recoveries” related to 44 birds, most of which are from Palmarin (39), the others being from Technopole. Adding other sightings in Senegal of these same birds (mostly by Ngoné Diop), we have a total of 103 recoveries.
Here’s a quick summary of their origin:
- As can be expected, the vast majority are from Spain, particularly from the Ebro delta which accounts for about a third of all birds for which I know the origin (15 out of 44). Six are from Valencia (PN de l’Albufera, Salinas de Torrevieja), three from Tarragona (Salinas de Sant Antoni), three from the tiny Isla de Alboran between Morocco and Spain, and two each from the Balearic islands (Mallorca and Menorca), from Murcia (Parque Regional San Pedro del Pinatar and Isla Grosa), the Laguna de la Mata in Alicante, and the Chafarinas islands.
- Six birds are from Portugal, but I’m still awaiting information for full details of the five most recent birds (all from Palamarin early September); thanks to Ngoné I know that at least four birds (and likely all six) originate from the colony on Ilha da Barreta (the southernmost tip of the country, near Faro).
- Earlier this month I found my first Italian gulls at Palmarin, three adults (ICTD, ILBJ and K7T). I have not yet received details from the ringing scheme, other than that K7T was ringed in 1998 – so far my oldest bird! Ngoné kindly provided me with info for ICTD and ILBJ as these were already known to her, which allowed me to include Cagliari (Sardinia) and Isola del Giglio on the map below; I will add further info here when it becomes available [Olly Fox kindly informed me that K7T was seen at the Kartong Bird Observatory in The Gambia in November 2016; it was born on Isola dei Cavoli off southern Sardinia].
At least one Corsican bird has been found in The Gambia (Recorbet et al. 2011) and Ngoné has recorded a few French birds in Palmarin. One can assume that some Moroccan birds may also winter in Senegal, and maybe Algerian and Tunisian birds as well. Not quite sure where the Eastern Mediterranean populations spend the winter, but I read that at least some remain around their breeding grounds.
Here’s an example of the “life history” of one of our oldest birds¹, 45P from Spain, pictured in the header image of this post. It was ringed as a chick in 1999 on the Chafarinas islands, and was seen in The Gambia during the 2004/05, 2006/07, 2007/08 and 2011/12 winters, then in October 2014, October 2015, and September 2017 it was spotted in Palmarin (plus a few times on its native island, in April-June). Could it be that many Audouin’s Gulls spend the initial 4-5 months of the non-breeding cycle in Senegal, then move to The Gambia for the remaining 2-3 months of the northern winter?
The age composition of our wintering Audouin’s Gulls varies considerably between areas and apparently also through the season. This was first documented by del Nevo et al.: “Adult birds dominated both surveys and proportionately more adults than first year birds were present during September 1992 than in February 1991. Our observations are consistent with the view that adult Audouin’s Gulls tend to arrive in Senegambia before first year birds; the ratios of first year to adult were 0.1:1 in September and 0.54:1 during February.” Delaporte & Dubois reported an overall proportion of 15% of immatures. These ratios have likely changed now, at least in terms of the seasonality now that some immatures can spend their first summer in the region. Ngoné and colleagues reported estimates of 278 adults and 167 immatures (= 37,5%) in Palmarin for the 2013-2015 period. They also found that adults, 3rd and 2nd winter birds arrive earlier than 1st winter birds, a difference which “is probably due to differences in experience among age classes.”
The differences in “immature-to-adult” ratio between Palmarin and Technopole are striking, and I wish I knew what causes this. Immatures are by far outnumbering adults at Technopole, as opposed to the high proportion (70-80%?) of adults further south, particularly in the Saloum delta. Interestingly, this may not have always been the case: Oro & Martinez mention that juveniles winter further south than older 2-3y gulls, in the Senegambia region: “After the breeding season, 2-3y and older gulls were recovered mainly at the E and S Iberian Peninsula coasts. During the winter season these gulls moved southwards, especially to the Atlantic coast of Morocco. Juveniles behaved differently, moving further south than 2-3y and 4y or older gulls, reaching the Senegambia coast in high percentages (81,8%).” Is it possible that this was at a time when a new generation of young birds was in process of establishing an overwintering tradition in Senegal and The Gambia, returning in subsequent winters? That would explain why there are currently more adults than juveniles.
Two ringed individuals show how birds wintering in Senegal will typically spend their first year around the Cap-Vert peninsula, before moving on to the Saloum delta once they are older: BNH5 was ringed as a chick in June 2011 in the Ebro delta, after which it was seen at Technopole in July 2012, but during its third winter in Dec. 2013 (N. Diop), and again in Sept. 2017, it was in the Palmarin lagoons. AWNV, born in 2010 in Mallorca, was first at Technopole while in its second summer (July 2012), while in 2015 and 2016 it was in Palmarin. Some birds already move to Palmarin during their 2nd winter (e.g. BWU9), or even 1st winter (BPZ9, seen by Simon in January 2013, then by Ngoné in December of the same year and in Oct. 2015, and last month I saw it again. Talk about site fidelity!
All ringed birds recovered from Technopole were at most two years old, though of course there are some older birds and every now and then a full adult will show up. BYPB is a typical first-year bird, seen here in March 2017.
Among the ringed birds that I have found there are quite a few old individuals, the oldest being nearly 20 years old. Indeed, Audouin’s Gull is a long-lived species with a high adult survival rate (and relatively low fertility). The oldest bird I have is from Italy, at 19 years, while from Spain there’s 45P and 66P, both born in 1999; Ngoné had already seen both in 2014 and 2015 in Palmarin; 45P and was again at Palmarin earlier this month, while I saw 66P there last year at the end of August last year.
The little chart below shows the distribution by age at the time of the last sighting, for 43 birds for which I have the ringing year (birds are typically ringed as chicks, usually in June, so we know their precise age). One can clearly see the predominance of birds in their first year (= juveniles and 1st winter), though this is hardly surprising given that these all correspond to Technopole recoveries. I don’t know how to explain the near-absence of two- and three-year old birds.
Ngoné’s systematic visits to Palmarin have resulted in some 500 ring readings, which of course allow for a more thorough analysis than my anecdotal observations. Through modeling the team has estimated annual survival rates and the size of the wintering population in Palmarin, which are summarised in this informative poster presented at PAOC just about a year ago. There are of course also a few interesting individual stories in the lot, such as two Spanish birds that were ringed on the 15th and the 19th of June 2015 respectively, and that were seen within a few weeks after they left their colony (25/8/15 and 15/9/15).
To be continued…
Many thanks to Ngoné Diop for her input!
¹ The oldest bird we have is “FDA”, ringed as a chick in June 1988 (!) at Islas Columbretes, Castellon, and seen in 2015 and 2017 in Palmarin, and in Dec. 2017 in The Gambia.
When I started birding nearly 30 years ago, Audouin’s Gull was one of those near-mythical birds, endemic to the Mediterranean and listed as an Endangered species on the IUCN Red List. Plus, it’s a real pretty gull, much more attractive than the standard “large white-headed gull”. Fortunately, this highly coastal species has seen substantial increases in its breeding population and has (re)conquered new localities, mostly during the nineties.
It is now found in Portugal (where it didn’t used to breed 30 years ago), Spain (where the bulk of the population breeds), France (Corsica), Morocco, Algeria, Tunisia, Italy, Croatia, Greece, Cyprus, and Turkey. The largest colonies are in the Ebro delta (14,177 in 2007) and the Chafarinas islands off NW Morocco (2,700 pairs in 1997). The Ebro colonies now represent about two thirds of the global population, so it is particularly of note that the species wasn’t even breeding there in 1980: Audouin’s Gull established itself in 1981 when 36 pairs bred, with as many as 4,300 in 1990, +10,000 pairs in 1993… and now certainly more than 15,000 (I didn’t immediately find any recent figures).
The species’ global population is now thought to number 63,900-66,900 individuals, with 21,300-22,300 breeding pairs: to write that this is “a significant increase from an estimated population of 1,000 pairs in 1975” certainly is an understatement… This remarkable feat is thought to be a result of the increased availability of effectively protected areas during the 1980s and of discarded fish from trawlers, particularly around the Ebro delta. Although it may still be vulnerable due to its small number of colonies, it was downlisted to “Least Concern” during the 2015 revision of the Red List, previously being considered Near Threatened (2004), “Lower Risk/conservation dependent” (1994), and Threatened (1988) (IUCN). Quite a conservation success story.
Following a good harvest of ring readings a few weeks ago in the Saloum delta, I wanted to find out a bit more about its history, trends, abundance and distribution in Senegal – and decided to turn it into a blog post here. This wasn’t too difficult given that a ton of research has been done on Audouin’s Gull, resulting in decent knowledge on its population dynamics and structure, distribution, breeding ecology, dispersal, feeding and migratory strategies, etc. The main challenge was to identify the most relevant resources and to distill everything into something relatively concise. And for once there’s even fairly abundant literature on the species in its wintering grounds here in West Africa.
First, let’s have a look at historical records of Audouin’s Gull in Senegal, and see if we can reconstruct the trends for the country.
The ’60s and ’70s – the first records for Senegal
We automatically turn to our rapidly deteriorating copy of Morel & Morel (1994), who only list a handful of records – essentially, the first four records for the country:
An immature collected at Saint-Louis, 11/5/61 and an adult seen on Gorée island (Dakar) on 13/3/64; one photographed at “the entry of the Sine-Saloum” [wherever that may be! I assume near the Saloum river mouth?] on 1/2/75, and one record near Dakar at the end of December 1981.
Dupuy (1984) adds the observation of an adult in the north of the Saloum delta on 13/12/80 but this record was either overlooked, or not retained by M&M. Interestingly, De Smet & Van Gompel (1979) did not encounter the species even though they covered large chunks of the coast between lac Tanma and the western Saloum delta, as well as the Senegal river delta, during the 1978/79 winter. This seems to confirm that Audouin’s Gull at the time was still a rare or very scarce visitor here – something which was about to change very soon.
The ’80s and ’90s – establishment of a wintering tradition
Moving on, Sauvage & Rodwell (1998) consider Audouin’s Gull to be “frequent at PNLB (Langue de Barbarie NP) and Saint-Louis, Jan.-Apr. with max. 17 birds, Jan. 1994, nine ringed in Spain. Up to 10 were wintering around Saint-Louis, 1990-91.” It is “frequent to common Dakar off Pointe des Almadies and Toubab Dialao, Jan.-Mar., max. 104 (four ads.), Toubab Dialao, Jan. 1992. Frequent to abundant Saloum delta. Max. 321 wintering.” The latter figure, obtained in 1985 (Baillon 1989) is significant as it is the first mention of a substantial number of birds in Senegal, and can likely be linked to the “explosion” of the Ebro delta colony. In Jan.-Feb. 1988, Delaporte & Dubois counted gulls all along the Senegambian coast, from the Mauritanian border to Casamance, and counted 81 Audouin’s Gulls (6 near Saint-Louis, 3 along the Petite Cote, 72 around Palmarin) though they estimate a total of 130 birds. They also mention the presence of 185 in the northern Saloum (probably Palmarin/Joal-Fadiout) on 6/12/88. Del Nevo et al. (1994) conducted counts in February 1991 and in September-October 1992, noting a total of 459 birds in Senegal and 72 in Gambia (1991), and 276 in Senegal the following year, mainly at Sangomar and Joal-Fadiouth.
A few eBird records from the early nineties provide some more context for that decade, in particular the count of no less than 470 birds at the Somone lagoon on 28/2/91, with two at Mbodiene (south of Mbour) a couple of days earlier, and 12 at Plage de Hann (Dakar) on 18/2/91 (O. Benoist). Bengtsson (1995) reports a minimum of 456 near Palmarin in Nov.-Dec. 1994. Based on these records, it looks like the species became a regular winter visitor to Senegal in the early to mid ’80s, and rapidly established a number of traditional wintering areas during that decade.
The next comprehensive figures are reported by Schepers et al. (1998) based on waterbird counts from January 1997 in the Saloum delta and along the Petite Côte. The team counted a total of 858 Audouin’s Gulls between Dakar and the delta, with the majority (673) found in the Saloum, and 185 along the Petite Côte. They estimated the wintering population to number around 1,000 birds, while in 1988 the same areas (incl. Saint-Louis) held at least 80, but more likely at least 130 Audouin’s Gulls (Delaporte & Dubois 1990, though Baillon & Dubois in 1991 estimated the number of wintering birds to be around 500, without providing further details). Regardless, these numbers suggest that Ichtyaetus audouini continued to increase in numbers throughout the late eighties and nineties, and confirmed that Senegal plays an important role for the species during its non-breeding cycle.
2000 – 2017 – stability
Fast-forward a few years to the first decade of the 21st century: hardly any published data! The only citations of the species that I could find are from seawatch sessions and a few trip reports. For instance from 2006, when a Swedish team counted migrating birds off Ngor, from 10–14 and 25–26 November: 28 Audouin’s Gulls were noted on three separate days (Strandberg & Olofsson 2007). A year later, a more comprehensive migration study at Ngor, with impressive numbers of seabirds counted from 5-28 October, resulted in a total of 692 birds. In the Senegal delta, a maximum of c.15 birds were counted in 2002 (Triplet et al. 2014).
In January 2011, some 50 Audouin’s Gulls were counted by Ottvall et al. at Lac Rose, providing “more evidence of the increasing numbers […] wintering along the coast north of Dakar.” Later that year, Paul Robinson reports two 2nd calendar years from Lac Tanma, which seems to be the first mention of the species here (I’ve seen two birds on 28/8/16 here, but not during other visits in 2015-17). Paul also recorded the species in Popenguine, where on 12/2/12 the pond had “a few” Audouin’s gulls amongst the gulls.
In July 2012, Paul counted c.150 Audouin’s Gulls at Technopole, noting that these were “all sub-adult birds from 2010 and 2011, represents a real increase in summering birds south of the Sahara and a West African summer record count. Several had Spanish rings.” Indeed, Audouin’s Gull can now be seen year-round in Senegal.
Ngoné and colleagues estimated the Palmarin “winter” population to number 445 individuals (278 adults, 167 immatures) based on the modelling they performed on their monthly counts and ring recoveries from the end of 2013 up to end 2015. This seems rather on the low end given that at peak times in October they recorded up to around 700 birds, and that in recent years it’s easy to find more than 300 birds together in the lagoons along the Samba Dia road – surely there are many others scattered throughout the western Saloum delta, e.g. around Sangomar and further south. More on the findings of their study, which was presented under the form of a poster at last year’s PAOC, will be discussed further down.
Current distribution in Senegal
The winter range of the species in Senegal probably hasn’t changed much in the last 20-30 years, with the following areas being regularly used by Audouin’s Gulls:
- La Grande Côte: Langue de Barbarie and elsewhere in the Senegal delta around Saint-Louis (shores, beach and lagoons), though never in large numbers, with a maximum of c.65 birds in Jan. 2013 (Triplet et al. 2014). On the southern end of the coast, the species is regularly seen at Lac Rose and sometimes at Lac Tanma. It probably also occurs along the beach throughout (I need to ask Wim about this!), especially around the larger fishing towns and villages: Kayar, Mboro, Lompoul, etc. At Lac Rose, ca. 350 birds were seen on 11/2/18, suggesting that this is still an important roosting site for the species, at least during part of the northern winter.
- Cap-Vert peninsula: Regular at Lac Rose (e.g. c.60 on 8/8/15, 2 on the beach on 22/1/17, 5 on 14/5/17) and Technopole, where most numerous in January-March, but records from all months except for September (when I rarely visit Technopole); so far my highest count has been a modest 50 birds on 12/3/17. Birds are also regularly seen from Ngor, either migrating or, more often, feeding out at sea. In autumn and winter, one should be able to see Audouin’s Gull pretty much all along the coast from the Pointe des Almadies along Yoff all the way to Lac Rose. I really need to check out the Hann bay from time to time, as there are often lots of gulls and terns. The species has also been reported from Yene-Bargny where is likely still a regular visitor, and may well be numerous at times (in autumn maybe? Birds may favour Technopole later in winter).
- La Petite Côte: the Somone lagoon seems to be the most regular site, but birds also show up at least irregularly at Popenguine and Mbodiene, and likely feeds off-shore along the entire coast here.
- Saloum delta: this is of course the main wintering area, that likely holds about 80% of the Senegalese wintering population. Birds are typically concentrated in the lagoons to the north of Palmarin, and do not gather far inland. It should also occur further south in the delta but I have no data from there.
- Coastal Casamance: the only record I know of is of two birds on 12/10/16 flying north along the beach at Diembering. There certainly are more records (though none on eBird nor observado.org) as Casamance must be the far end of their regular range, given the absence of sightings in nearby Guinea-Bissau.
In terms of population size, my own conservative guestimate puts the current number on 800-1,000 birds, so not any different than the 1,000 birds estimated to winter in Senegal in January 1997, which logically reflects the species’ stable global population trend.
Elsewhere in West Africa
Isenmann et al. (2010) enumerate lots of records for Mauritania, but little or no info is provided on the evolution of the wintering population in the country, probably because of a lack of historical data. The current status is that of a regular migrant and wintering bird, with at least several hundreds of birds along the coast. Far more birds are said to winter along the Western Sahara coastline. The Gambia is also part of its regular winter range, mainly on and around the Bijol Islands, Tanji Bird Reserve. In 2007/08, about 500 Audouin’s Gulls were counted there. The first Gambian record, as per Morel & Morel, is of a bird at the Bakau Lagoon on 21/2/82.
Surprisingly, the species hasn’t yet been seen in Guinea-Bissau, which is most likely right outside the regular winter area, but surely a few individuals must reach the NW corner of the country, and particularly the Bijagos, given that they are recorded at least from time to time (it would seem) in Casamance and that Gambia is less than a 100 km away from the border. My Oct. 2016 observation near Diembering was barely 20 km from the border and both birds were moving north… In Guinea, the first record was obtained just last year by gull expert Peter Adriaens, a first-winter near Cap Verga on 28/10. The lack of other records from Guinea (and Guinea-Bissau) most likely reflects the absence of observers in the country, rather than a real absence of Audouin’s Gull which surely must at least from time to time reach Guinean waters. This is not the case in relatively well-watched Ghana, where the species is a true vagrant: a first-winter on 13/1/14 was quite an unexpected first for the country, as it had not previously been reported south of Senegambia (Kelly et al. 2014). [note that the species certainly doesn’t winter in Gabon, contra BirdLife International’s species fact sheet].
Now, I still wanted to talk about the origin of wintering birds in Senegal and summarise current knowledge based on ringing recoveries, but my blog post is already getting a bit long… that part will have to wait for a second installment, hopefully a week or two from now.
Yesterday’s weekly Technopole visit once again turned up a new species for the site. I’d been scanning and counting the numerous waders on the SW end of the main lake for over an hour, when I turned my attention the flock of Greater Flamingos that were feeding nearby. Two ringed birds proved to be tricky to read, one ring being very faded and the other one, also on an adult bird, was largely covered in mud – more on this further down in this post. I then started to count the flock, and after reaching the 200 mark (there were a total of 289 birds, so nearly 120 more than last week), I noticed a much hoped-for different shade of pink, darker and more intense: an adult Lesser Flamingo!
The noticeably smaller size, bright orange eye, and largely uniform dark crimson bill (or is it vermilion?) bill quickly confirmed the ID.
As far as I know, this is the first record of the species at Technopole, though of course that doesn’t mean that it hasn’t already occurred here: it may well have gone unnoticed or else unreported (which given the lack of any sort of bird observation recording system or central database would not be surprising! More on that in another post…)
It’s definitely not an unexpected addition (as predicted a few months ago), given that the species must regularly migrate along Senegal’s coast between the Senegal and Saloum deltas. However, neither Morel & Morel nor Sauvage & Rodwell mention the species from the Dakar atlas square. This bird obviously got mixed in with a group of Greater Flamingos, possibly on their way down to the Saloum or moving between post-breeding dispersal areas in the region (Lac Rose, and soon maybe Lac Tanma when it will start filling up).
Lesser Flamingo is listed as a Near-Threatened species on the IUCN Red List of Threatened Species. In short, the “NT” category typically includes declining or otherwise vulnerable species that in the medium to longer term are faced with the risk of extinction; as such they are likely to qualify for a threatened category in the near future. Despite having a vast range in the Old World, covering large parts of sub-Saharan Africa and the Indian subcontinent, Phoenicopterus (or Phoeniconaias) minor breeds only in a handful of sites in the world, with just six main colonies located in Mauritania, South Africa, Namibia, Botswana, the Tanzanian Rift Valley, and NW India. Other sites may be used irregularly, e.g. in Kenya and Pakistan.
Its global population is still pretty substantial with some 2-3 million individuals, mostly in East Africa, but it is extremely vulnerable to changes in conditions of those very few sites, whether induced by climate change or by a range of human disruptions to the environment. For instance, the IUCN species’ fact sheet tells us that “the proposed large-scale soda ash extraction at Lake Natron, the most important breeding colony, although currently on hold, would be disastrous for this species and, were this to happen, the species may qualify for uplisting to a higher threat category.” Read up a little bit more about this conservation issue and the actions that BirdLife and partners have taken here. Excessive predation by Jackals, African Wolves and even Warthogs and Honey Badgers may result in poor or even complete failure of breeding success. And at least in Mauritania poaching is also a problem.
The West-African population is thought to number about 15,000-25,000 birds (compared to over a million for East Africa), concentrated in the lower Senegal valley with the most regular breeding site being the lagoons of Aftout es Sâheli in the Diawling NP in southern Mauritania. Up to 46,500 birds have been counted in the Senegal delta (Feb. 1990), but breeding is not annual: according to Isenmann et al. it occurred only in 1965, 1988 (though all attempts failed that year), 2000, 2005, and 2010; it was suspected but not confirmed in 1998, 1999 and 2007. More recently, the species has bred at least in 2014 (a bit more info is available on the Diawling NP’s website, and see this video from the parc).
Its movements, and generally speaking its overall ecology, are largely dictated by feeding conditions as it is a highly specialised species; as a result, birds tend to respond rapidly to changing water levels and food availability (spirulina and other blue-green algae, small invertebrates). Fun fact: the Lesser Flamingo’s bill contains up to 10,000 microscopic lamellae!
At least one of the ringed Greater Flamingos was Spanish: I don’t have full details as I’m yet to submit the sighting, but judging by the code (white ring with black inscription “2|CZR”) it’s a bird that was ringed in 2013 at the Laguna de Fuente de Piedra in Malaga, which is also the origin of one born in 2014 and seen in June 2015 at Technopole. Coincidentally, the three ringed birds from the Camargue that I found last year were seen on the same date as yesterday’s birds: 6 August.
Other than that, there was an interesting gull that will require a bit more work, and probably better pictures, in order to establish its ID. I’m suspecting Kelp Gull because of the massive bill and the large, stocky appearance, but am by no means a gull expert and will want to consult a few others first (contributions welcome!). I’ll get back to this one in due time – if it is indeed a Kelp rather than Lesser Black-backed Gull, one of which was present nearby, then it would mean yet another potential addition to the site list.
As I mentioned, I’d been counting waders for the first hour or so, which I continued doing on the opposite end of the pool close to the golf club house, where more birds were feeding. This resulted in some pretty good numbers especially for Ruff with a minimum of 598 (!) birds, at least one of which was colour-ringed with a yellow flag in combination with other rings – unfortunately it flew off shortly after I’d found it, never to be seen again… probably a Dutch bird. Some of the males were still largely in breeding plumage, such as this one:
Another wader highlight was the very decent diversity of calidris sandpipers: two summer-plumaged adult Dunlins, no less than seven Knots (my highest count here), with a supporting cast of several Curlew Sandpipers (9), Sanderlings (11) and Little Stints (12). There were now only 22 Black-tailed Godwits and just one Marsh Sandpiper, while the four Avocets seem to have finally moved on. Two Common Sandpipers on the other hand were most likely newly arrived birds.
[Note (13/8/17): it turns out that the Lesser Flamingo had already been photographed on August 3rd by J-M Dupart, but apparently was not identified at such at the time; I triple-checked my pictures of the flock that was present on 29/7 but it definitely wasn’t present at the time.]
It’s been a while since my last update from Technopole, which I was fortunate to visit quite regularly these past few weeks, taking advantage of not travelling much at the moment (something that will end soon, having trips to DRC, Cote d’Ivoire, Cameroon, and Morocco lined up for the next two months).
So, what’s about at Technopole? Water levels continue to drop, rendering the main lake more and more attractive for a range of species. The panorama above attempts to give a bit of a feel of the area for our readers (click image to enlarge). Lots of gulls and a good range of waders are the key features at the moment, the following being some of the highlights:
- Garganey: a single male on 25/2. Besides a few White-faced Whistling Ducks, there are hardly any ducks around these days.
- African Swamphen: this is a fairly common resident here, but a very discrete one… so seeing an adult carry plant material for its nest, on 3/3, was a good breeding record.
- Avocet: one on 25/2 and 3/3. Fairly scarce visitor to Technopole.
- Kittlitz’s Plover: two birds on 12/3 were new for the season: my previous record here dates back to early August 2016, before the rains. It seems that this is mostly a dry season visitor to Technopole, possibly an irregular breeder when conditions are right (including last year, when a very young bird was seen in June though no adults were observed in previous months).
- Yellow-legged Gull: an adult on 3/3 and at least two (adult and 3rd winter) on 12/3. Last winter only one bird was seen here.
- Common Gull: the same bird as on 12 February – Senegal’s fifth – was seen again on 3/3, when I showed visiting birder Bruce Mast around. The very worn plumage makes it straightforward to identify this as the same individual, which may hang out around the harbour or the Hann bay when not at Technopole (addendum 5/4:/17 Jean-François Blanc saw what was most likely the same bird on 24/3, meaning it will have been around for at least six weeks).
- Mediterranean Gull: two on 25/2 (1st and 2nd winter), and Miguel Lecoq reported two first winters on 4/3 meaning that so far at least three birds are around.
- Little Tern: an adult on 3/3, shortly resting with the other terns and gulls (and at one point sitting next to a Caspian Tern, nicely illustrating the huge size difference between the two species). The (near-) absence of black on the tip of the bill indicates that this is the local guineae subspecies. Not a frequent visitor to Technopole – my only other record was last year I only saw two on 28 August. They seem to be more regular at Ngor in September, though still far from common.
- Whiskered Tern: an adult in breeding plumage was present on 3/3, bringing the total number of tern species seen that day to six.
- Barn Swallow: one passing through on 12/3
- Copper Sunbird: a pair on 12/3 was my first record in a long time here. They were on the edge of the gardens in the NE corner. So far I’d only seen a single male on 17 and 24/4, presumably the same bird – more frequent visits to the vegetable garden areas would likely result in more observations as this must be a resident in the area.
- Zebra Waxbill: surprisingly, what is probably the same group as on 28/1 was seen again on 3/3 in exactly the same spot, near the small baobab past the golf club house. This time we counted at least 16 birds and I even managed to get a few decent record shots.
On the ring-reading front, new birds were added to the list on each visit, with 11 birds “read” on 12/3 alone: one French Spoonbill (+ another, probably Dutch, that flew off before I could make out the ring combination), two new Norwegian Lesser Black-backed Gulls, three Audouin’s Gulls, four Slender-billed Gulls, and the now usual Gull-billed Tern “U83” all from Spain. Except for the Spoonbill, all rings were read in the flock of gulls and terns that’s visible on the panorama shown at the top of this post. My recent post on ring recoveries from Technopole was updated with this new information.
More to follow shortly I hope – am going back to Technopole tomorrow morning. For today I have some more seawatching to do, with spring migration slowly picking up it seems, and good numbers of skuas (mostly Pomarines but also several Arctic Skuas and even an a-seasonal Long-tailed Skua last week), Northern Gannets and Cape Verde Shearwaters feeding off Ngor.