Tag Archive | Horus Swift

Of lists, listing and listers: how many bird species in Senegal?

I have a bit of a confession to make. I’m a bit of an obsessive lister, always counting and collecting birds, new ones if at all possible. Or rare ones. I have a Life List, a Senegal List, Africa, Western Palearctic, a Technopole list. A list of colour-ring recoveries. And so on. Maybe not as far as keeping year lists or garden lists or self-found lists or lists of birds seen while writing up blog posts, but still I’m pretty much counting species all the time. I won’t go through great lengths to “tick” new birds and I don’t take the whole listing thing too seriously, neither will I keep track of my buck-per-bird expenditure rates (yes, it seems that some birders calculate this), but still… lots of obsessive listing.

I’m sure that some of our readers will recognise this – do we need group therapy? Maybe it’s just human (male?) nature, to be collecting and classifying things. Some of these lists may actually be quite useful especially when covering little-known regions as I sometimes get the chance to do on my work trips (think South Sudan, Somaliland, Burundi…), but for the most part they’re just my own little checklists sitting in an old Access database… time to upgrade, right?

Baird's Sandpiper / Becasseau de Baird

Baird’s Sandpiper / Bécasseau de Baird, Technopole – Senegal’s second record (and first documented) and a personal lifer

 

Luckily there’s still lots of new species to be counted, we’re not quite done yet – I’ve only seen less than a quarter of the world’s birds, mostly in Africa (ca. 1,370 species, Wilson’s Indigobird a couple of weeks ago near Lac Togo being the most recent addition), so there are still many new ones to discover.

By now, my Senegal list stands at about 495 species, after three and a half years of pretty active birding in the country. But how “good” is 495? How many species have been reliably recorded in Senegal? This may be an easy question, but the answer is certainly not so straightforward. First of all, what taxonomic reference to follow? Depending on which reference one uses, certain subspecies are elevated to species rank while others are not, and with current tendencies to split species it can be hard to keep up with the understandably dynamic nature of bird taxonomy.

AdamawaTurtleDove_Wassadou_20180616_IMG_2663

Adamawa Turtle Dove / Tourterelle de l’Adamoua, one of Senegal’s “specials” that can reliably be seen in the south-east

Several years of “service” in the Swiss national rare bird committee and a French regional records committee taught me a bit of discipline in keeping count of records and numbers for rare or scarce species, in ensuring appropriate documentation, in reassessing status of vagrants and scarce migrants, keeping track of changes in taxonomy and advances in identification criteria, and so on. And then there’s the status categories: “A” (species occurs naturally in the wild, seen at least once in modern ornithological history, eg. since 1950), “B” (same as A but not recorded since the cut-off year), “C” (introduced exotic species that have established autonomous breeding populations), “D” (the dreaded uncertain origin category), and finally “E” (escapes). Only species that are in the A, B or C categories are part of a country’s national list. In Senegal, the only established exotic species appears to be House Sparrow (unless Eurasian Collared Dove is also introduced or escaped, though this is far from certain; wild Rock Doves apparently still exist in the Kédougou escarpments).

So, in order to answer our question of the number of species occurring in Senegal, let’s start by identifying an appropriate taxonomic reference. The IOC (International Ornithological Committee) is nowadays usually considered the standard authority, being followed by many countries and authors. The Handbook of the Birds of the World (HBW) is another reference, I guess a bit more progressive than IOC, and was adopted by BirdLife and the IUCN. I won’t go into reviewing the differences between these and other lists such as Howard & Moore or Sibley, though we should mention that the African Bird Club follows IOC which as such should be an obvious choice here. Unfortunately, the ABC is not very good at remaining up-to-date to the extent that the current version dates back to 2010 – and at the time of writing, the page to download country checklists was non functional… The ABC now also has new “Dowsett country lists” which are largely based on the more conservative Howard & Moore taxonomy. More than anyone else, the Dowsetts are of course a major reference in their own right when it comes to African birds, and it would be great to have up-to-date checklists for each country. To make matters more complex, the ABC also links to checklists by their “partner” iGoTerra; unfortunately, their Senegal list is highly unreliable as it contains about a dozen species that have never been recorded in Senegal as well as several obvious missing species… and I assume that it’s the same for other countries. Really surprising (and disappointing) that the ABC endorses these lists. Similarly, other country checklists, e.g. the Avibase list, contain several serious errors and should be avoided. As such, we hope that the Senegal list that we’re making available here will be of use to local and visiting birders alike.

Either way, we settled on the IOC list – the choice of which can of course be debated, but it seems to make sense given that ABC is following it and that there is no proper reference committee for Africa (such as the AERC for Europe, though they’re not quite as authoritative as they ought to be, with many national committees following different standards). Anyway… let’s move on.

PelsFishingOwl_Wassadou_20180616_IMG_2615

Pel’s Fishing Owl / Chouette pecheuse de Pel – one of the most recent additions to my own Senegal list, and a much anticipated lifer.

 

So, I took the African Bird Club country list for Senegal as a starting point, and updated it as per the latest IOC version. As our regular readers will surely know, quite a few species have been added to the national list in recent years, so these were of course included in the list. Several species on the ABC list are marked as uncertain, since at the time no proper documentation existed, such as Blue-throated Roller and Black-and-white Mannikin. I’ve removed those that seem unlikely, as well as Tropical Boubou which is yet to be confirmed (and I replaced Red-fronted Warbler, which was included in error, by Cricket Warbler). I’ve added Vieillot’s Black Weaver based on the account that Lesson described this species in 1840 based on a specimen from Casamance (it’s on the Gambian list, but not on the ABC list for Senegal). Here again, in the absence of a national or regional rare birds committee, these are personal choices and I’d be happy to revise these if there’s a good case to do so.

Below are the new species seen in the last 12 years, in chronological order. Those  marked with a * were formally documented, typically through publications in the ABC Bulletin or in Malimbus; records with a ° symbol await publication or will be written up shortly:

2018 01 5, 14h38. Doué de Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7122 (3)

One of the Horus Swifts / Martinet horus found in January 2018 at Gamadji-Sare (F. Bacuez)

 

On average, that’s just one or two additions per year – though note how 2012, 2016 as well as 2018, only half-way through, already stand out with no less than three new species. Also note how four out of these 18 records were also new to sub-Saharan Africa or even the African continent as a whole: Western Sandpiper, Short-billed Dowitcher, Black Guillemot, Eyebrowed Thrush. The records of Eurasian Collared Dove and Horus Swift, both possibly/probably breeding, constitute major range extensions in West Africa. The fact that another four of the above records are from the Dindéfélo area is also quite remarkable: it just shows how a previously largely ignored border area harbours several species that just creep into the country. Dakar, being relatively well watched in recent years, also stands out as a national “hotspot”, as is the Gandiol/Langue de Barbarie area to a lesser extent.

Add to this list the Canary Islands endemic Plain Swift, which thanks to geolocators was recently shown to transit through Senegal on its way to the newly discovered wintering grounds in Sierra Leone, Liberia and Guinea (Norton et al. 2018) – a nice example of modern technology solving one of the many remaining mysteries in the field of migration. Eleonora’s Falcon is another species that was confrmed to occur thanks to satellite tracking programs (Gschweng et al. 2008) but that is yet to be seen in natura.

Then there are two special cases, both of hybrids: a Greater x Lesser Spotted Eagle, that was GPS-tracked from its Central European breeding grounds into Mauritania, Senegal and Gambia; neither of the parents have been confirmed from Senegal as “pure” birds, but does this mean that this bird somehow needs to make it to the national list? To a lesser extent, the probable Woodchat x Red-backed Shrike seen last year is also an interesting case since the latter parent species has never been recorded in Senegal, though there are records from nearby Mauritania. Logically, hybrids should not be included on the national list, but I’d be happy to be convinced otherwise (in this specific case though, we cannot be 100% that the second parent of the hybrid shrike was indeed a Red-backed Shrike).

Woodchat x Red-backed Shrike / Pie-grieche a tete rousse x ecorcheur

Presumed Woodchat x Red-backed Shrike / Pie-grieche à tête rousse x écorcheur, Lac Tanma, Aug. 2017

 

So now for the list: with the recent additions, and following the latest IOC taxonomy, we end up with at least 671 species. The full list is available HERE as a handy Google spreadsheet  – of course it’s work in progress and I’d be happy to receive contributions. You’re more than welcome to download the list as an Excel file and use it as a checklist for the country. I did include a small number of species for which there are unconfirmed older records but that are likely to be present; these are marked with a ? in the list, and if confirmed would bring the total to 676 species. One of these is likely extinct in the wild by now: Common Ostrich, marked with an “E” (and Secretarybird probably shares the same fate though could still show up as a wanderer). Vagrants are listed as “V” in the list; for some of these – e.g. Little Gull – it’s not quite clear whether they should be considered as true vagrants or whether they are merely rare migrants that do in fact make it to Senegal on a more or less regular basis.

For those who tend to prefer the HBW/BirdLife taxonomy, the Senegal list should be at least 664 species – quite surprisingly this is quite a few species less than the IOC list, due to several splits that aren’t recognised by HBW (Boyd’s & Barolo Shearwaters are treated as part of Audubon’s Shearwater, White-breasted Cormorant is a ssp. of Great Cormorant, Yellow-billed Kite is rather suprisingly considered conspecific with Black Kite, Barbay Falcon part of Peregrine Falcon, African Reed Warbler a ssp. of Eurasian Reed Warber, and Atlas Flycatcher a ssp. of Pied Flycatcher). The only additional species is Seebohm’s Wheatear which surprisingly is not recognised by IOC, despite it being very distinctive from Northern Wheatear. Other splits do not directly affect the number of species on the Senegal list, though names may differ (e.g. Black-faced Firefinch is now known as Vinaceous Firefinch Lagnosticta vinacea, endemic to West Africa). When I find the time, I’ll also include a link to the HBW country checklist.

There are probably a few other species missing from the list, as not everyone goes through the effort of writing up notes or publishing pictures of potential first records. For instance, what would be the first record of Cinereous Vulture was only just recently uploaded to eBird and while it certainly seems like a credible observation, I’m awaiting further details from the observers. Likewise, there’s only one formally published record of Citrine Wagtail, but I found a reference to another observation that pre-dates the 1999 Technopole bird, which was mentioned along with a succinct (but in my view sufficient) description in the waterbird expedition report by Schepers and colleagues (27.1.97 at Djiffer, Saloum), and found out recently that a British tour operator that regularly visits Senegal has a few records of the species from Nianing. Once again, a real shame that the commercial birding companies rarely contribute to our knowledge of the areas that they visit. Corrections are more than welcome of course.

MeadowPipit_Yene_20180101_IMG_7903

Senegal’s first Meadow Pipit / Pipit farlouse (Yene-Tode, 1.1.18)

 

What will be the next species to be added to the country list? One can surely make a few predictions in terms of what species are likely to be added in the future – think various American vagrants with Ring-necked Duck and White-rumped Sandpiper being the most obvious candidates (and why not Wilson’s Phalarope or Solitary Sandpiper, or a Forster’s Tern or maybe even a Stilt Sandpiper), tropical seabirds such as Swinhoe’s Storm Petrel, Fea’s and Black-capped Petrels or Masked Booby, various desert passerines (Dunn’s Lark in particular should be sought for in the far north, White-crowned Wheatear is also a good possibility in winter), songbirds from northern Europe and Siberia such as Richard’s and Olive-backed Pipits or even Little Bunting, all of which have been reported from Mauritania. The lists goes on and on really – lots of potential to find new stuff!

Key areas to search for northern and American vagrants are of course the coastal wetlands, while the northern border regions should be targeted for winter vagrants and desert species. Finding new seabirds will likely require pelagic trips and a decent amount of luck¹ – and it’s likely that seabird monitoring programs that use satellite tracking will turn up some new species in Senegalese waters. For those lucky to go out birding in Casamance, chances are that Turati’s Boubou and Preuss’s Cliff Swallow are already established in a few localities and that they are just waiting to be discovered. Quailfinch Indigobird may well occur but apparently remains to be confirmed. And for those making it to the far south-east, why not search for Rock Pratincole which should occur at least occasionally along the Gambia river (or even along the Falémé), or try for low-density species that occur not too far out in Mali or Guinea of the likes of West African Seedeater and Cabani’s Bunting, and that may well just creep over the border into Senegal.

And then there are of course those species that one may expect the least, such as our Horus Swifts earlier this year – an incredible range extension (if confirmed to be regular) of some 1,600 km at least. Or Damara Tern, known from a single recent record from Mauritania (in 2006, Isenmann & Benmergui 2018). Only time will tell – what’s clear is that there’s still lots to discover.

Now, time to get out there and find new birds. And keep listing.

Thongbird

 

Bram, with useful contributions by Simon and Frédéric – merci à eux!

 

¹ and chum.

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Those Mystery Swifts: Horus, New to Senegal

(see also this Ornithondar post on the same topic, en Français!)

Back in January, when Frédéric Bacuez (Ornithondar), Filip Verroens and I visited the middle Senegal valley, we stayed the night at Gamadji Sare on the Doue river bank in the far north of the country. We had some really good birds here, such as Egyptian Plover, Red-throated Bee-eater, Fulvous Babbler, Cricket Warbler, and Seebohm’s and Isabelline Wheatears. We also encountered a flock of swifts which we initially took for White-rumped Swift as these had been reported from the Senegal valley before and since in Senegal this is the only swift with a white rump other than Little Swift.

However, something felt not quite right for this species, and luckily Frédéric was able to take a number of decent pictures – not an easy feat with these birds! Subsequent study of the pictures revealed that the birds did indeed not quite fit White-rumped Swift, and that they were something else… Frédéric was lucky to pay a second visit to the same site, in mid February, and despite very dusty conditions he obtained even better pictures. These provided a more definite clue to the identity of these mystery swifts, which we now feel confident are nothing less than HORUS SWIFTS!!!

2018 01 5, 14h38. Doué de Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7122 (3)

Horus Swift / Martinet horus (© F. Bacuez) (1)

2018 01 5, 14h40. Doué de Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7125 (3)

Horus Swift / Martinet horus (© F. Bacuez) (2)

 

Why do we get so excited about this one? It’s always exciting of course to find an addition to a country’s species list, but in this case we have a highly unexpected record since it comes down to a range extension of no less than 1,600 km, and because the species may even breed here. Plus, one can now safely assume that Horus Swift also occurs in Mauritania, Mali and Burkina Faso, and why not in northern Cote d’Ivoire and NE Guinea too (and for any WP listers out there: it may well make its way across the biogeographical border!). It also shows, once again, that there’s still so much to learn and to be discovered about birds in Senegal despite it being among the better explored countries in West Africa.

So far, the closest Horus Swift observations to Senegal were from Ghana, more precisely from Mole National Park and a few other locations in the NW of the country where they were first found in 2004, though it’s not clear whether these were incidental records of wanderers or whether the species is a resident here. It has also been recorded from SW Niger (‘W’ NP), several plateaux in Nigeria and the highlands in Cameroon, but only becomes relatively widespread in the highlands of East and Southern Africa.

HorusSwift_XC_map

Horus Swift range map from xeno-canto

 

On hindsight, the identification as Horus Swift is actually relatively straightforward, the key id features of Horus Swift being the following:

  • Broad rectangular white rump patch extending well onto the sides of the lower flank (not narrow and U-shaped as in White-rumped)
  • Moderately forked tail, intermediate in depth between Little and White-rumped Swifts
  • Absence of white trailing edge to secondaries (a feature that’s almost always present in White-rumped)
  • Overall structure and flight action closer to Little than White-rumped Swift, which is a slender bird with a graceful flight.

All of these are clearly visible on the pictures, some of which are shown below (merci Fred!). The option of a hybrid Little x White-rumped Swift was initially suggested, but all features fit Horus perfectly, and a hybrid would be slimmer with a smaller throat patch and some white edges to secondaries. Plus, it would be (near) impossible to have 18-20 hybrids together, without any pure birds. All swifts looked similar in the field, though pictures reveal that there may have been a Little Swift in the lot as well (picture here). A presumed hybrid was reported from Spain recently, see this eBird record. Our identification was confirmed by Gerald Driessens, illustrator of the reference guide to the swifts of the world.

2018 01 5, 16h17. Doué à Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7133 (4)

Horus Swift / Martinet Horus (© F. Bacuez) (3)

2018 01 6, 8h40. Doué de Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7362 (4)

Horus Swift / Martinet Horus (© F. Bacuez) (4)

 

The next three pictures are from February 12th, i.e. some five weeks later than our first observation when Frederic and Daniel Nussbaumer visited the site. Only a few birds were present, at least one of which showed a heavily worn plumage, see picture (6). Besides the shallow tail fork and large rump patch, the extensive white throat patch extending onto the upper breast is obvious here.

2018 02 12, 16h41. Doué. © Photo par Frédéric Bacuez,IMG_9557 (3)

Horus Swift / Martinet Horus (© F. Bacuez) (5)

2018 02 12, 16h28. Doué. © Photo par Frédéric Bacuez, IMG_9503 (3)

Horus Swift / Martinet Horus (© F. Bacuez) (6)

2018 02 12, 16h28. Doué. © Photo par Frédéric Bacuez, IMG_9506 (3)

Horus Swift / Martinet Horus (© F. Bacuez) (7)

 

Here’s a more detailed description, largely based on the ca. 50 pictures by Frédéric :

Structure: typical swift build with a body shaped like a fat cigar and long and pointy wings, and a moderately forked tail, the fork being about a third of the length of the outer rectrices when closed.

  • The wing shape resembled Little Swift much more than White-rumped, which has narrower wings. It often appeared to be fairly broad, particularly in the middle (inner primariers and outer secondaries). As can be seen on several of the images, the wing shape varied considerably throughout the birds’ flight action – for instance, compare pictures (3) and (4) which give very different impressions, and see also (8).
  • The tail always appeared to be broad throughout, never pointed as is often the case in caffer (1) & (2). When completely fanned out, the fork appeared very shallow, quite similar to House Martin (2). At times it disappeared nearly entirely, thus resembling Little Swift: compare (6) and (7), of the same bird taken at an interval of a few seconds.

Plumage

  • Overall very dark brown to black plumage except for the white throat, the very pale forehead extending to just above the eye (4), and the white rump;
  • The rectangular white rump patch (4) clearly extended onto the flanks and was thus visible from below, e.g. pictures (5) and (6).
  • The throat patch was similar to or larger than Little Swift, obviously extending onto the upper breast. Both features are nicely visible on (6) and to some extent on (1).
  • Several photographs clearly show the relatively contrasting underwing pattern, stemming from a combination of paler brown leading edge-coverts, dark lesser underwing coverts, again paler median coverts, and slightly darker greater coverts – see header picture and (3) and (6). In White-rumped Swift, the lesser and median coverts are all darker than the remainder of the underwing.
  • Upperwing entirely dark, without white trailing edge to secondaries. The latter appear slightly greyer or browner than the black mantle and scapulars (the “saddle”).

Voice: slightly lower-pitched trills than Little or White-rumped Swift; the short sound recording that I managed to obtain can be found here and contains two different calls, including a typical shrill swift call and a slower “twittering” of more melodious quality. It matches the recording by C. Chappuis quite well, both by ear and on sonogram, even if I find it hard to hear clear differences with some White-rumped Swift recordings (compare with e.g. this recording from Zambia). HBW describe the most common Horus call as a reedy trilled ”prrreeeeoo” or “prrreee-piu”. Of note is that until now, no recordings were available on xeno-canto or other online sound libraries.

Behaviour: the swifts were mostly feeding over the river and nearby banks, though usually remained above the water at various heights, occasionally flying right above the surface. They mostly remained in a loose flock, sometimes with 2-5 birds flying closely together and swooping close to the sand bank above which we were standing, sometimes calling in the process – a behaviour that’s indicative of breeding… The picture below shows two such birds “chasing” one another.

2018 01 6, 8h40. Doué de Gamadji Saré. © Photo par Frédéric Bacuez, IMG_7362 (3)

Horus Swift / Martinet Horus (© F. Bacuez) (8)

 

Below are a final few pictures from the January series:

 

Now compare with these pictures:

  • Horus Swift

Horus Swift / Martinet horus (© C. Cohen, on ABC website)

Horus Swift / Martinet horus (© S. Helming, on IBC website)

  • White-rumped Swift

White-rumped Swift / Martinet cafre (© S. Harvančík on IBC website)

White-rumped Swift / Martinet cafre (© H. Teichmann on IBC website)

 

The habitat in which we found these birds is also very much in line with what is to be expected from Horus Swift. Quite unlike most (all?) other swifts, the species breeds in “old burrows of bee-eaters, kingfishers and martins” (Borrow & Demey), i.e. typically in sandy banks along rivers – exactly the kind of place where we found these birds, which were seen “visiting” the Gamadji Sare cliff (approx. 6-8m at its tallest). Our swifts either rested on the cliff, or inside holes: at dawn on 6/1, several birds visibly left the river bank while the previous evening they were flying very close to or into the cliff, oftentimes calling (unfortunately, because we were positioned on top of the cliff, we could not confirm that they actually entered any nest holes). We estimated there to be about 18-20 birds on Jan. 6th, while the previous afternoon we saw just four.

It may thus even breed by the Doue river which likely has Pied Kingfisher and Blue-cheeked Bee-eaters, and possibly also Red-throated Bee-eater nesting here – something that we really ought to confirm in coming months (just before, during, or right after the rains?). White-rumped Swift typically breeds in disused swallow or Little Swift nests, though sometimes also “in crevices or on ledges within rock fissures or buildings” (Chantler & Driessens 1995). It may well breed at Popenguine for instance, where in September 2015 I saw two birds entering and leaving one of the World War II bunkers.

GamadjiSare_20180105_IMG_8461

The Doue river by Gamadje Sare

 

As I was typing this up, I started wondering why a rather unassuming little bird such as this one was named after one of the most significant ancient Egyptian deities. Well, I’m not quite sure! It was described in 1869 by German zoologist Theodor von Heuglin, who spent many years in north-east Africa in the mid-19th century. One can assume that he collected the type specimen in Sudan or especially in Ethiopia where Horus Swift is locally fairly common. And that Heuglin somehow must have been inspired by Horus, depicted as a falcon-headed man, when coming up with a name for this species.

 

Many thanks to François Baillon, Simon Cavaillès, David Cuenca, Ron Demey, Gerald Driessens, Miguel Lecoq, Carlos Sánchez and others who commented on the identification or provided reference material.

 

Bram & Frédéric (une co-production Senegal Wildlife & Ornithondar!)

 

References

  • Chantler, P. & Driessens, G. (1995) Swifts. A Guide to the Swifts and Treeswifts of the World. Pica Press.
  • Chantler, P. & Boesman, P. (2018). Horus Swift (Apus horus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.