Acro from hell

30 05 2013

“Turkey is a European country, an Asian country, a Middle Eastern country, Balkan country, Caucasian country, neighbor to Africa, Black Sea country, Caspian Sea, all these.”

– Ahmet Davutoglu, Turkish Ministry for Foreign Affairs

After almost 2 weeks with easterly winds and both an Eastern subalpine warbler and a Spanish sparrow already in the ringing season summary, it’s worth to pay attention to every bird we catch in order not to miss any of the more cryptic taxa. This practice proved to be useful with Siberian chiffchaff but some other species/subspecies are even harder to be pointed out. A worn Iberian chiffchaff, an eastern form of Lesser whitethroat… If you feel asleep, you’ll miss your chance!

Today’s bird was a cold-toned Acrocephalus warbler. My first thought (keeping in mind the bird from Gedser, Dk) was a Blyth’s reed warbler, but a quick look revealed the darkish centres of the tertials, the non-emarginated p4 – I’m still saving a bottle of very good Venezuela rum for the first time I’d see an emarginated p4-  and, moreover, flight feathers were too fresh, reminding more of a Marsh warbler; I would expected them to be worner in a spring Blyth’s due to moult timing.

Acrocephalus scirpaceus

However, the overall coloration was strikingly cold, with grey-olive edges in both greater coverts and tertials, a paler rump and mantle and a greyer nape and crown. The pictures below show the mantle and the edges of both tertials and GCs of a normal Reed warbler (in the left) and the cold-toned bird (in the right). The difference is huge…

Upperparts

GC edges

With a wing-length of 66, our next thought was a VERY small Marsh warbler. The primary’ wear fits with this species and the overall coloration (despite arguably greyer in this bird) could be closer to Marsh rather than to Reed. But the structure of the bird was not that of a Marsh warbler. The head looked big in relation with the rest of the body and the bill was long, with the typical shape of a Reed warbler. The notch in p2 (as shown in the photo of the primaries below) was also too long for Marsh and the nails were almost as dark as in a Reed. This comparison shows today’s bird (in the top) and a Marsh warbler (in the bottom). Note not only the shape of the bill but the shape of the nostrils, being more rounded in Marsh.

bill comparison marsh reed warblers

The next plausible explanation was the bird being a Caspian Reed warbler A. [scirpaceus] fuscus, the Asian race of Reed warbler. Despite its still discussed taxonomic status, it’s actually a quite distinctive form, keeping in mind the big mess that these Western – Eastern forms of old-world warblers usually are. Everything seemed to fit since, to summarize, fuscus shows a Reed warbler structure with a Marsh warbler moult (later in the winter, not starting before December), just as our bird. The tail also presented some funny white spots in the tips of the feathers. My experience with Reed warblers in the Iberian Peninsula tells me this is not a reliable feature, at least not when there is only this amount of white, but, nonetheless, even some scirpaceus can show it, all the fuscus must show it.

Tail pattern reed warbler

Moreover, the white tips of the primaries also pointed to fuscus. Some fresh scirpaceus can show this white tips, but they use to be restricted to the outer web of the feather. In this bird, however, the white was in the whole tip, what includes both webs of the feather. Also, the the primaries were more square-shaped than they usually are in a Reed warbler, as described in the literature. And last but not least, the distance between p4 and p3 was really small, much smaller than in a typical Western Reed warbler. You can see these features together with the notch in p2 (too long for a Marsh) in the pictures below.

primaries rump

notch square p5

Unfortunately, not everything fitted with fuscus. The relative position of p2 did correspond with scirpaceus, equaling p4, whereas in fuscus it should fall between p4 and p5. It seems there is a lot of variability among the Reed warbler complex in that sense so let’s see if a fuscus can also show this aspect of the wing formula.

wing formula

The feather samples are on its way to be analysed. In the meanwhile, and just to have fun, here it is my bet: Caspian Reed warbler Acrocephalus [scirpaceus] fuscus.

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Still hungry

29 05 2013

“The Tortilla Española, in the English language is referred to as Tortilla, Spanish Omelette or Spanish Tortilla; not to be confused with the Mexican maize tortilla.”

– Spanish omelette, Wikipedia.

Same time last year I got Spanish sparrows breeding in the park just by home at La Laguna, Canary Islands, but it’s interesting to see how the excitement produced by finding a bird depends on how rare it is. This year, instead, I am living several thousand kilometers north of my missed archipelago and here the Spanish sparrow is rare, very rare. Therefore, a bird coming from the sea shouldn’t be one, but it was. You can even smell the overall happiness in this video that Björn recorded while I was showing the bird. It would remain forever in Falsterbo’s history (thanks Youtube ¬¬) as well as the photo that Stephen did take showing the bird with the lighthouse behind. By the way, quite impressed about the number of twitchers that came to see the sparrow, keeping in mind it was a Monday morning. What would had happened the day before?

Seemingly, following what did occur with the Finish Fox sparrow, it’s the same bird seen at Småland a few days ago (in what was the first record for Sweden) but when I found it I was sure it may be the second record for the country. Why? Because passerines in Spain are not usually re-found, especially when the new place is almost 200 km south of the original. We live in a strange world…

Spanish sparrow

Fortunately, this was not the best bird of the day for me. In the last net-round of the morning and in the bottom shelf of a mistnet, a Greenish warbler was waiting to be ringed. Yes, in the bottom shelf. As well as the 2 rosefinches we’ve ringed so far. Again, we live in a strange world…

Phylloscopus trochiloides





Parcel delivered

21 05 2013

EXCESS, n. In morals, an indulgence that enforces by appropriate penalties the law of moderation.”

– Abrose Bierce, The Devil’s Dictionary

Many thanks for the one who has kindly sent to us a package of eastern birds!

After some days with the right easterly winds but low numbers of captures (ironically because it was too windy), the eastern species has finally reached the Peninsula. We had been waiting for the Sunday all the week long but not because of holidays (a ringer doesn’t know what they are) but because it was the day when the wind was supposed to drop.

Things finally changed on Saturday night, when we went to twitch a River warbler just south from Malmö. The bird started to sing just 5 minutes after we arrived. Nicer than expected!

The Sunday started quiet, with just a few birds in the first net round. However, there was something magic in the atmosphere. I know it’s easy to say this after the event, but I promise it was! The actual excitement started when we caught a nice female Collared flycatcher. Just to make it even more interesting, the bird had already been ringed, but we still don’t know what’s the origin. All of us did agree a nest-box in Gotland was a good guess.

Ficedula albicollis3

By the way, the bird was not specially intriguing. We aged it as a 2nd cy based on primary and primary coverts color and wear. The white on the bases of the primaries extended to p5, but p4 also showed a whitish area. With the closed wing, the white was well visible since it was much more extensive than the length of the primary coverts. The pattern of the tertials was very nice, with the large part of the white edge elongated to the tip of the feather, not giving the stepped impression typical from Pied. I find this feature really hard to assess from photos of a bird in the field and it’s always interesting in that sense to refresh your mind while studying and in-hand bird. After a proper analyse of the characters, it was time to relax and enjoy the pattern of the nape feathers. The white line under the grey tip is almost completely hidden, but it’s probably what gives the impression of a collar in a female Collared.

Ficedula albicollis2_blog

It was then when Jonas decided to leave. What in the beginning seemed a responsible decision of a responsible family man, turned out to be a mistake. Fortunately, nothing that could not be sorted out! 1 hour later, Jonas came back because we had caught an Eastern Subalpine warbler. The bird looked perfect for an Eastern, but it made things even easier when we released and it decided to call. You can hear a recording by Stephen already at xeno-canto.

http://www.xeno-canto.org/embed.php?XC=134173&simple=1

Sylvia cantillans albistriata

To end with the eastern bonanza, a nice walk around our house produced 2 red-breasted flycatchers. I never get tired of seeing them.

Ficedula parva

Not happy with that, today we caught an almost perfect Siberian chiffchaff. Buffish tones in the cheeks, complete eye-ring (cream in the upper part), grey back, white undertail coverts and underparts, green fringes in flight feathers, some yellow feathers restricted to the underwing… perfect. The only crappy thing is the extension of the pale basis of the bill. Maybe it’s too extensive, but the shape (slightly curved in the tip of the upper mandible) also points to Siberian. As a gift for our handling skills (despite we took quite a lot of measurements…) the bird subtly called as a Siberian. I say “subtly” and it actually was, but Stephen managed to record it. However, I would not be the spoiler.

Phy col tristis

Phy col tristis2





The pendulum theory

17 05 2013

“We are not going in circles, we are going upwards. The path is a spiral; we have already climbed many steps.”

– Hermann Hesse, Siddhartha

Many things have happened in the last 10 days. The notable changes in the weather had come with notable changes in the quantity and quality of the captures in what can be considered an inversely proportional relationship. In the first days, we were catching many birds. Everyday was a good one in terms of numbers, with some new arrivals too, but the most exciting species were wood warbler, thrush nightingale, lesser redpoll (first for the season!) and red-backed shrike. Apart from quantifying the impressive migration of barnacle geese (up to 50.000 birds counted from Nabben in a few hours), the rest of the day consisted mainly in ringing willow warblers and enjoy the good weather.

Luscinia luscinia

Carduelis cabaret

Phylloscopus sibilatrix

Lanius collurio

As expected, somebody turned off the migrants tap and the number of birds ringed started to decrease. Probably “somebody” means Arvid, whose presence blocked the flux of birds for a few days. Suddenly, we realized the pendulum was already in the other side and there were no birds at all. However, we managed to catch some house martins and to rescue some amphibians stuck in the pit of the lighthouse garden. A common toad, a green toad and a smooth newt (this one a lifer for me!) were, without any kind of doubts, the best of that day.

Bufo viridis

Triturus vulgaris

Bufo bufo

Arvid left but, while literally crossing the door, he kept on predicting something good for the next days. The weather forecast indicated strong winds and hot temperatures from the southeast and this time it was right. These last days of ringing are among the strangest days of ringing I’ve ever seen. We’ve been catching around 10 birds per day, but surprisingly (or not) 3 red-breasted flycatchers, including a very nice adult male that started to sing after being released. There were at least 5 different birds around the garden, together with some (the first) common rosefinches. If anybody knows the explanation of this high proportion of red-breasted flycatchers, I would be more than happy to pay attention. It’s worth-saying that, until now, we’ve caught 4 pied flycatchers and 3 red-breasted. Nothing else to say.

Ficedula parva

Carpodacus erythrinus

The hot temperatures have also brought some dragonflies. The downy emerald Cordulia aenea was a lifer for me, but the four-spotted chaser Libeulla quadrimaculata is also common species up there and scarce in the Iberian Peninsula, where it’s restricted to the high Pyrenees.

Libellula quadrimaculata

Cordulia aenea

The influence of the easterlies is obvious but the pendulum is only in the middle. We need the wind to drop and see if the inverse proportion between total number of captures and exciting species finally disappears. If so, it would be amazing. Sunday is the day.





Ode to a wader

6 05 2013

“Tell me what you’d like to hear me sing. I’ll sing whatever you like, after which I will take up a collection, if you don’t mind…”

– Edith Piaf

It’s not the first time I’ve realized my life has changed by looking at which species I am targeting at work. One year ago, I wrote a similar post about Laurel pigeon and today, it’s time to take a look to another species that is breeding close to the place where I am living: the Dunlin. These 2 species seem to share opposite fates: while Laurel pigeon is experimenting a notable increase due to hunting prohibition and habitat protection, Southern dunlins Calidris alpina shinzii are declining dramatically.

Calidris alpina

Everybody knows the Arctic is in serious trouble. The increase of the global temperature together with the accumulation of contaminants is leading most of Arctic species to extinction. However, the firsts changes in their populations can be noticed further south, in the little spots of tundra (or its equivalent southern moorland habitats) where these species do also breed. Sometimes these areas are well-protected and local researchers are not able to explain why the population of such species keeps on decreasing. In these cases, the conservation strategies must be global, acting in the heart of the populations, sometimes in places where a decline has not been noticed yet. This means to study the still healthy populations, assessing their threats, even if they come from further south like contaminants or occur further south like human pressure in wintering grounds. To ensure the main range of a species guarantees its future and it would be the species itself who would send advanced scouts to establish satellite populations in this isolated southern spots of habitat.

Vellinge Angar

Vellinge Angar2

I am working in one of those spots: southwestern Skåne. The population of dunlins here is fragmented and declining despite the big effort performed by local researchers. Vellinge Ängar is already my favourite area among the 8 comprising the breeding bird survey. It’s a beautiful wet wasteland, with some channels across carrying water from the adjacent farmland area to the main lagoon. Migrating waders forage along the muddy shore, always in large numbers, while the breeding species display in the middle of the heath. Oystercatchers, redshanks, lapwings, ringed plovers, avocets and of course the dunlins make up a orchestra that plays every morning, even (who knows if especially) when there’s nobody to enjoy it.

In the first visit to the area, I saw 4 males dunlin and 2 females. All the males were crazily singing, but both females seemed to belong to the same lucky male, a very old one ringed (as an adult) in 2006. Males are supposed to take care of the brood and therefore a shorter bill is positively selected, since it is useful to forage in terrestrial habitats. The short bill is also typical of Southern populations C. a. schinzii, so the short-billed impression in males schinzii is quite impressive. Moreover, the date of arrival of breeding dunlins seems to be correlated with bill length and body mass. The pairs composed by a small and short-billed male and a big and long-billed female (like the gorgeous TC) arrive earlier to the breeding grounds, while the pairs composed by average-sized birds arrive later (Jönson 1987). Most of the birds I saw were short-billed males and long-billed females, what make me hope yet another arrival of dunlins in the following days.

female TC yellow

male R_green L_red_white

Despite this fact, the number of dunlins in the area already represents a remarkable increase with respect to last year’s numbers. A promising breeding season for them, in the end! There’s still a long way to success, but at least the initial settings couldn’t be better.








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