Thursday, March 27, 2014

River stuff

In the last blogpost I posted some photos of a Common Snipe (Gallinago gallinago). I wanted to do a something specially for that bird, and here it is!

It was a second-year (EURING 5). It can be a little bit tricky I think, but this bird have some interesting things. I have to say thank you to Stephen Menzie for his comments on ageing!

As in many wader species, juveniles do a partial postjuvenile moult and adults a complete postbreeding moult, with a partial prebreeding for both age-classes. The main question I had when I aged it was 'How extensive would be the prebreeding moult?'. Following Cramp et al. (1983), both adults and 1w usually moult many body feathers, scapulars, some wing coverts (lesser and median) and maybe tertials. They moult between February and May, and actually that bird was just moulting a few feathers (and for that there were just a little few prenuptial feathers).

The coverts pattern can be sometimes hypnotist if you look at it too much time. During the autumn is probably easier, but now in spring, most of the juvenile feathers had been replaced. Still, it seems that maybe 1w have a different upper wing covert pattern, a 'postjuvenile pattern'. But the thing, at least in this bird, in on the marginal coverts. There, you can see some retained feathers that i would expect to be juvenile.


Tertials and tail are usually moulted by spring so they may not be as useful as they can be in autumn. Also the same with scapulars and matle feathers.


Looking at the whole wing properly, three other features supported the second-year theory. One was the wear on primaries, also the thin white border on primary coverts, but the other is maybe the most relevant one...

In the left wing (bottom photo), the biggest alula feather is retained,
and with juvenile pattern!
Here you have a comparision with alulas from an adult (left) and a 1st-year (right) taken in Falsterbo last August:

Comparing with our bird... (left wing to the right, and right wing to the left... just to compare with the photo above!)

Last Sunday I went again to Aiguamoll de la Sala again, and instead of a Snipe, we trapped a Green Sandpiper (Tringa ochropus)!
Photo by Bernat Ferrer
After the Snipe thing, and although they're quite different, I think that many things are the same with this ochropus. Looking at the whole wing at first sight, some things attracted my attention.


Juveniles undergo a partial postjuvenile moult that involves body and some wing coverts. Later on they can moult tertials and they also have a partial prenuptial moult, just some more body feathers, scapulars and maybe one tertial involved, quite restricted. Adults do a complete postbreeding moult and a partial prebreeding involving body, scapulars, tertials and some wing coverts.

'Juvenile' feathers have bigger white spots, anf this is specially noticeable on tertials. Nonetheless, they seemed to be moulted (and it makes sense with the moult strategy).


Looking for moult limits on wing coverts, there were two abvious feathers generations, specially noticeable on marginal coverts and also in median coverts. Also, just a few, very local feathers seemed to be prenuptial.


There was the same on the back, with different generations easy to spot.

At the bottom there's a mantle feather that is probably prebreeding.
Also, primaries (and secondaries) were quite worn. Tip of outermost primaries was pointed and not as wide as I would expect in an adult. So everything indicates to me that's a second-year (EURING 5).


Tail seems to be not so relevant in ageing, but is nice to see.


There was also some presumably retained feathers in head and breast, sometimes also seemed to be three generations.

Bernat came with me, and we had a really pleasant ringing morning. We catched another nice male Bluethroat (Luscinia svecica), an adult this time. And also this nice Zitting Cisticola (Cisticola juncidis).


Around 11:40 the raptor migration started. This place is in the middle of a bid drylands area, but many raptors follow the Llobregat river to cross some mountains on the way to North. The wind was on the right direction to push migrants to follow the river, and because of that, we saw 10 Short-toed Snake Eagles (Circaetus gallicus), a Marsh Harrier (Circus aeruginosus), 4 Black Kites (Milvus migrans) and a Red Kite (Milvus milvus). Also 11 Sparrowhawks (Accipiter nisus), 5 White Storks (Ciconia ciconia) and some other usual stuff. I was really excited when I saw an Osprey (Pandion haliaetus) really close (nice bird for inland Catalonia), and also a Black Stork (Ciconia nigra)!!


During the rest of the morning I cannot stop looking the sky at any time, while I was ringing some Blackcaps (Sylvia atricapilla) and Chiffchaffs (Phylloscopus collybita). The day finished with my first Willow Warbler (Phylloscopus trochilus) for the year, really nice to see a long primary projection finally! ;)

Tuesday, March 11, 2014

Ringing weekend

Spring has already arrived and I've seen my first Swallows (Delichon, Hirundo and Cecropis), Little Ringed Plovers (Charadrius dubius), Short-toed Snake Eagles (Circaetus gallicus)... and a really early Whinchat (Saxicola rubetra), a migrant that usually arrives during the first week of April.

Last weekend almost started on Friday morning, when I trapped this male Mallard (Anas platyrhynchos). It was an adult (EURING 6).


That afternoon, Joan and Bernat helped me in the last Yellowhammer's (Emberiza citrinella) ringing afternoon. I didn't expect to catch any bird, but we finally trapped 3! (and there were at least 9 around)


On Saturday morning I did a quick visit to Llobregat Delta, where this male Common Pochard (Aythya ferina) was showing off about his bill, sky-blue 'F=S'.


But the good ringing was on Sunday. I went to l'Aiguamoll de la Sala in order to try to catch some Reed Buntings (Emberiza schoeniclus) coming to the roosting. It was a nice surprise when we trapped this handsome Bluethroat (Luscinia svecica)!

2nd-year (EURING 5). Two outermost GCs are retained.
That afternoon I also trapped a Stonechat (Saxicola rubicola), some Zitting Cisticolas (Cisticola juncidis), Corn Buntings (Emberiza calandra), collybitas, schoeniclus and other usual stuff.

On Monday morning I came back to that place to catch more 'March-migrants'. I felt really lucky in the first netround when I saw a Common Snipe (Gallinago gallinago) hanging in one net in the Llobregat river.


As interesting birds, I also caught a Grey Wagtail (Motacilla cinerea), two Kingfishers (Alcedo atthis), a thirsty Cirl Bunting (Emberiza cirlus) and a nice male Penduline Tit (Remiz pendulinus)!

'Flappy' Grey Wagtail
Adult male Kingfisher
2nd-year (EURING 5) female Cirl Bunting
Adult (EURING 6) Penduline Tit
I really want to feel migration soon... Let's see what kind of surprises is this spring keeping for us.

Thursday, February 20, 2014

Ghosts doesn't exist

During last month I've been trying to catch Moorhens (Gallinula chloropus) in my usual ringing place, l'Aiguamoll de la Bòbila. I made up a kind of cages and I put some clap traps and I've been feeding this places. Moorhens found the food soon, and I decided to open the cages and try to catch them.

During the first morning I trapped a Coot (!), but no Moorhens around.
Two weeks later, moorhens managed every day to eat all bait and scape. In one of the cages was almost impossible to get in and then go out, but I don't know how the hell they managed to do it daily. The other trap have a platform and when a bird touches it, the door falls and the bird is trapped inside. Well, not Moorhens because they ate all the bait and scaped without activate nothing. Mission impossible.

I was very surprised, and I wanted to be sure that Moorhens were going inside the cages, and not mice or other things. I prepared an automatic camera... and the first bird I photographed was this Grey Heron (Ardea cinerea).

The next morning I got want I wanted. But... in the first photo there's only the cage, and in the following one, some bread has dissapeared and the Moorhen is outside the trap!! In addition of being quite clever, they are fast... Or maybe they are ghosts, or maybe ninjas.


21 days (!) after daily deceptions, but also improvings... I trapped one!!


The bird should be an adult (EURING 6), probably a female.


As other Rallidae species, adults undergo a complete postbreeding moult, and juveniles a partial postjuvenile moult. Also, both age classes have a partial prenuptial moult, usually quite restricted. I found Javier Blasco's notes quite interesting, take a look here (I've only found the Spanish version online).

9th primary (outwards) is quite wide close to the tip
Looking at the primary projection with the wing closed,
inner PP are very squared.
Bright red tibia and bright yellow tarsus.
All underparts are dark, with any white feather in between.
Look at the Javier Blasco's work, for more photos of different age-classes.
Following Cramp et.al. (1979) this bird may be a female by measurements. Also the shield was quite small and rounded. More 'significant' measurements are Bill lenght (to feathering on lores), tarsus lenght, middle toe lenght and wing lenght. Females are generally smaller than males.