Sunday, March 17, 2013

Morrocco!

Today I'm leaving to Morrocco for 17 days. I will be ringing in Yasmina for a week and then I will do 'the typical tour' around the country.

You can follow the ringing campaign in Yasmina (Merzouga), in this blog.

Have some good migration days!!

Wednesday, March 13, 2013

'Progressive greying'

Some days ago I trapped an adult female Blackbird (Turdus merula) that show some white feathers around the head. In fact, it isn't a strange thing in common species like merulas and House Sparrows (Passer domesticus).

The presence of some white feathers is usually called a leucism, a phenotype resulting that means a reduced pigmentation (in birds, feathers usually turns pallid or white). But this case isn't produced by high frequencies of genus that order leucism feathers, it's produced by the 'progressive greying'. Just like us, older birds show more grey/white feathers caused by the age. You should read that article, where is better explained.

'Generally with blackbirds, their breeding success increases with age when they are more successful at nesting.
'A bird with white feathers would suggest to the opposite sex that they are experienced breeders.'

(taken out from the article mentioned above)


I recaptured that female Blackbird last Saturday. The bird was first-trapped in May 2012, already with white feathers. I managed to take some more photos.

Tuesday, March 5, 2013

Herrings

Last Sunday afternoon I went to Tarragona harbour with Albert Cama. The main objective was find a Caspian Gull (Larus cachinnans) because of the winds coming from east during some days before. Also, Herring Gulls (Larus argentatus) are regular winter visitors there, with +10 birds/year. The Herring Gull is a rarity in Catalonia, but quite regular in winter, specially in Tarragona area.

Last year, on 18th February, I went there with Camilo Albert. we coudn't see any argentatus, but I could enjoy other harbour inhabitants. Camilo, who joined us this Sunday too,  is very interested in the Booted Eagles (Aquila pennata) that pass the winter in the port. Last year we saw 3 birds and we could enjoy one of them very close, eating a Pigeon.

Actually, the strong point of the harbour for the Booted Eagles, some Buzzards (Buteo buteo) and Peregrine Falcons (Falco peregrinus) that overwinters there is the big, big concentration of Rock Doves (Columba livia domestica) and Eurasian Collared Doves (Streptopelia decaocto)... it's like a big self-servicve restaurant. But the authentics port's stars are GULLS.
Black-headed Gull (Larus ridibundus) area.
Gull meeting.
Coming back to this Sunday, Albert found the first argentatus just when we started our search. It was a 2nd winter bird, that hasn't been seen before.


Later, a 1st winter bird appeared. Albert told me that was another 'new' bird for the port, and as he had seen 4 different birds the day before, it will be probably 6 or more argentatus there. You can follow him in his fantastic blog, very recommended!


We passed some time looking for ringed Lesser Black-backed Gulls (Larus fuscus). They are very common there in winter, where is easy to see birds from many Europe countries. We saw birds from England, Germany, Denmark, France...


We saw two argentatus, 1st winters, more (photos below). So no cachinnans, but 4 argentatus in a single afternoon it's not bad! But I couldn't have been possible without Albert Cama's help... Thank you!!

I'd like to finish these post with a short consideration:
Gulls are a very special group. The individual variation can be really surprising and disconcerting, and if you don't have some experience, sometimes is difficult to know what are you seeing.
It's easy to see common species ressembling rarities, so every unexperienced birder should take care with his ID. As example, this Yellow-legged Gull (Larus michahellis). It's a pale bird, very worn, with an interesting head structure. But, as Albert told me, it can be rapidly recognizable as a Yellow-legged because of the moult (1w argentatus only moult mantle and scapulars feathers, but never any covert), that bird have some coverts moulted, so we can think rapidly that it's not a Herring.

Saturday, March 2, 2013

Still in winter

This morning I went to La Cerdanya, in the Pyrenees. The snow still remains in the main part of mouintain and in the most humid valleys, and with it, some winter visitors. Between some Mistle Thrushes (Turdus viscivorus) flocks, it will be possible to see some Fieldfares (Turdus pilaris) (today I didn't find anyone... but probably some pilaris were laughing close to me).

Cadí Mountains, views from Estana, a hamlet.
El Fornell, close to Aransa.
There was, still, more than 60 cm of snow...
 Despite I wasn't lucky with the Fieldfares, I saw 9 Redwings (Turdus iliacus), 3 Bramblings (Fringilla montifringilla), two typical winter visitors, and also a Grey Partridge (Perdix perdix), that is quite scarce.
On pine forests, Coal Tits (Periparus ater), Chaffinches (Fringilla coelebs) and Goldcrests (Regulus regulus) are starting to sing... Spring is starting but, at the same time, is still away.

The sighting of the day is this female Bullfinch (Pyrrhyla pyrrhula), not for her rarity; it's for her beauty.