Blast from the past

12 08 2013

“Dreams are the genus; nightmares the species.”

– Jorge Luis Borges

It’s been already 5 years with the same idea hanging around in my head. It was in summer 2008, already in July but after a memorable spring migration plenty of eastern migrants. Joan Castelló caught an Acrocephalus warbler at Reguerons, Llobregat Delta, that immediately struck him as being something different. His first impression while extracting the bird from the mistnet was of a cold-toned reed warbler, very small. Later on, already taking the measurements, he thought about Blyth’s reed warbler, especially due to the position of p2. The only problem he could find was, as always, the lack of emargination in p4. The bird showed a hint of emargination, but this is usually present in the subsequent primary to the one emarginated, due to a higher exposure of this part of the feather and therefore a differential level of wear.

We were afraid of the possibility of a Blyth’s with a non-emarginated p4, so we asked both Killian Mullarney and Anthero Lindholm, who kindly replied giving extra reasons for ruling out dumetorum. Both agreed the edges of GCs and the centre of the alula were too warm, the supercilium too colorful and the primary projection too long.

Fine, the bird was not a Blyth’s, but, then, what was it? Neither Joan nor me were happy with just “2cy+ Reed warbler” and, during the last 4 years I’ve been looking at the pictures again and again, without reaching any conclusions. However, the Acro world has been shaken in the last months, especially in its southern boundary. News coming from North Africa talk about resident populations of African reed warbler Acrocephalus baeticatus breeding north of the Sahara, as close to Llobregat Delta as Morocco and Tunisia. By that time this possibility was not taken into account but it’s now worth-considering.

The overall appearance is indeed that of a cold-toned acro, especially the head and the nape but also the upperparts. After a spring ringing in Falsterbo, Sweden, I am aware about how grey a Reed warbler can be, but Iberian birds are much warmer. In that sense, this bird was quite different from the ones usually caught in spring along the Iberian Mediterranean coast. The eyebrow was quite indistinct, something that we knew didn’t fit Blyth’s, and there is a noticeable open-face impression. The bare parts were also striking. Admittedly, the bill is not as dark as described for nominal baeticatus, especially in the under mandible, but the shape is more triangular than in a typical scirpaceus. The legs are much darker, almost even darker than in a juvenile Reed, with a more contrasted yellow sole. These legs would be, in fact, the darkest I’ve ever seen in a 2cy+ Reed.

acrocephalus sp3

The biometrics are the most striking feature. The wing length was 62, in the lower end of Reed warbler range according to Svenson. P2 is surprisingly short, falling between p5 and p6, far from the typical p3-p4 of scirpaceus. The emargination in p3 is very long, taking up 2/3 of the visible part of the feather. Moreover, the notch in p2 is also long, ending below the secondaries; according to Jiguet et al. 2010, the notch should end below p8 in a Reed warbler.  Finally, the wear of the primaries indicates that the tip is p4 and not p3 as typical in scirpaceus.

acrocephalus sp

acrocephalus sp2

All these features fit African reed and rule out Reed but, as always in the acro world, is not that easy! The most misleading thing is that those short-winged birds are quite common in the Mediterranean and Southern Iberia. I’ve caught birds with a wing length of 58 and there are several claims of Blyth’s reed warbler in Southern Spain that were identified based on biometrics. I’ve heard that some of those birds didn’t match all the features for Blyth’s, but this species was the most similar. I wonder if those ringers, as we did 4 years ago, forgot about baeticatus and, lost in Svenson’s bible, didn’t manage to find the answer.

The moult, the song and of course some feather samples should be the key. Although the moult of primaries in breeding grounds is a criteria for African reed warbler, BWPi already gathers some cases of Reed warblers moulting primaries in the Iberian Peninsula, before departing to the wintering grounds. Marc kindly sent me the photo below of a bird in active primary moult caught at Ebro Delta in early September and a bird with a very advanced primary moult caught in Northern Italy also in early September can be seen by clicking here (log in needed). Note that Marc’s bird also shows a suspicious wing formula.

IMG_5017b

Some evidences points to the fact that baeticatus, or at least baeticatus-like warblers, do occur at least in the south and east of the Iberian Peninsula but further studies are required to confirm this point. Keeping in mind the short distance from the nearest breeding grounds recently described, it wouldn’t surprise me if some birds are found to be breeding. The taxonomic debate may start soon and we shouldn’t be surprised if the final outcome is the description of another clinal variation from North (or even South) Africa to Eastern Asia, this time with Reed warbler as the principal actor.

Photos by Joan Castello © (1, 2 & 3) and Marc Illa © (4)





Not yet in Sweden, I promise

24 02 2013

“I grow up in Chicago, and there was always snow. In Los Angeles there never was, so we would always import snow!”

– David Hasselhoff

I woke up yesterday morning with the sound of the snow heavily falling outdoors and for a moment I thought I was already in Sweden. My mother suddenly appeared to take me back to reality and then I realized I may be still in Barcelona. So… What to do? This badly-timed cold front is too late for an influx of northern wildfowl, so the only effect it may have may be a noticeable sedimentation of early spring migrants.

Finally, I decided to visit the Llobregat Delta, a good place for both migrants and wildfowl. The firsts views of the landscape were pretty unusual, with the plain surrounded by white mountains. It was cold, but there was no wind, so the conditions were almost perfect to do some birding.

Image

There were quite a lot crag martins flying over the Cal Tet lagoon and, among them, my first house martin. A pied wagtail had been sighted a few hours before, but I didn’t manage to find it. Moreover, it was plenty of wildfowl: more than 80 red-crested pochards, 300 shovelers, gadwalls, some shelducks, hundreds of teals, mediterranean, black-headed, yellow-legged and an Audouin’s gull… but the best was this female ferruginous duck, a bird always nice to see.

Image

A greater spotted cuckoo (also my first this year) flushed at Cal Nani marshes did demonstrate that spring is already in the air. The bird showed well, sat on a fence for a while and later moved to the top of a blackberry bush.

Image

We don’t have much time left till the arrival of the bulk of swallows, willow warblers and subalpine warblers, but let’s see where do I am when this happens.





Counting down the days

13 09 2012

“It’s like finding a needle in a stack of needles”

– Captain Miller, Saving Private Ryan

My last week in Barcelona, again. In 7 days I will be on a research vessel, counting birds and whales in the wonderful Galicia coast. Time goes by so slowly (thanks Madonna), even I am birding at Llobregat Delta most of days. The water level in Viladecans area (both Filipinas marshes and Reguerons) is nice for waders and there is a good diversity of them. 2 Temminck’s stints together with a Pectoral sandpiper are the highlights, but it’s worth to say there are also many Little stints, a Curlew sandpiper, some Dunlins, Snipes and lots of Wood sandpipers. I don’t know where are the redshanks…

The ducks are just arriving right now. There are good numbers of Shovelers (for the moment, most of them males) and Teals, but still missing the Wigeons and the Pintails. The best is a juvenile Garganey, a species always interesting in autumn.

In the surrounding area (composed by fields and orchards) there have been sightings of Citrine wagtail and Dotterel, but I’ve not been able to find any of them. However, on Sunday, it seemed it was a good sedimentation of passerines, specially Whinchats and wagtails. The Mediterranean gulls where feeding on the crops.

I am leaving on 19th. I don’t think I would find a big surprise before, but let’s try it!





Back to the cradle

9 07 2012

“Sleep, oh sleep, my dearest boy./I will cradle you. I will guard you”

– Henrik Ibsen

Visiting Llobregat Delta always brings me a lot of good memories. The field where I saw a marsh sandpiper last year, the fields where I found a Rose-colored starling, the reeds where I ringed an Icterine warbler, an Iberian chiffchaff, another Iberian chiffchaff, some Moustached… The day of the 7 White-winged terns, the day of the Cream-colored courser, followed by the day of the Broad-billed sandpiper. All of that, concentrated in the Prat de Llobregat area, what means memories can be multiplied by 2 if we take the whole Delta.

Back in Barcelona, to visit the Llobregat was one of the first things I had to do. There was a Blue-winged teal but I didn’t care actually… I wanted just to be there and see what the Delta could offer to me. July is not the best season to enjoy migration but only by seeing the local species, I remembered what “diversity” means. Since I’ve returned to the continent and seen even the most common species, I realized how hard it must be to colonize an archipelago such as the Canaries.

Both dragonflies and butterflies are at their maximum, and I was able to see the rare (the UICN declared it “Vulnerable”) Mediterranean skipper Gegenes nostradamus. It’s neither beautiful nor colorful, but it’s enigmatic and hard to see… that’s enough.

I didn’t have too much time to look for dragonflies, but I saw 7 species at a glance. Blue-tailed damselflies Ischnura elegans were mating while keeping an eye on the Black-tailed skimmers Orthetrum cancellatum. I looked at that during only 10 minutes, but I saw at least 5 catches of damselflies by the powerful skimmers. The Violet dropwings Trithemis annulata seemed to be quieter, maybe enjoying the show played by others’ frenetic life.

And what about birds? I didn’t see the teal. I saw a nice female in April while I’ve not seen a Black-winged stilt since long time ago. However, the best was a singing male Savi’s warbler Locustella luscinioides at Calaixos de Depuració de Ca l’Arana, an irregular breeder at Llobregat Delta. I don’t know if we are already in the dispersive period, but the habitat is suitable for the species and the bird was singing.





The lonely Crane

30 12 2011

Last tuesday Manolo García and me saw a flock of 10 cranes in active migration above Montjuic. One of them seemed to be tired or injured and all the time lagged behind. The rest of the flock came back, probably to carry on it, and the last image we saw was a flock of 9 cranes with one lonely crane behind heading southwards.

By chance, Xavi Larruy was working that morning in the airport, placed together with the Llobregat Delta. We had guess the cranes would landed in that area but it seemed birds just flew by. Late in the afternoon, Xavi saw a lonely crane landing at La Ricarda fields and the following days a crane has been seen at la Maresma de les Filipinas. The bird seems healthy, eating everytime, althought nobody has seen it flying… Let’s see how theLlobregat Delta can help a bird injured during migration.





Premiere at Llobregat Delta

29 12 2011

The first entry of that new blog would be like the others: my purpose is just to write a diary of birding and beyond. Let’s start with a good day at Llobregat Delta marshes.

The first interesting sightings were 3 Jack snipes in the Riera de Sant Climent, between Viladecans train station and the entry of the Remolar – Filipinas Natural Reserve. In La Vidala lagoon, a good diversity of pochards. First of all a female Common pochard with a nasal saddle. I’ve written to some ringers to know its origin…

Then, a female Ferruginous duck that can be seen anywhere in la Vidala.

And finally, some Tufted ducks of differents ages. Here, two 2nd calendar year males:

From the hides, the typical staff: teal, mallard, shoveler, gadwall, pintail and a single Common crane that deserves an entry…








%d bloggers like this: