Sunday, July 26, 2015

Orange is the new black

In late July, many adult waders are already in migration, specially the orange coloured ones: Red Knot (Calidris canutus), Curlew Sandpiper (Calidris ferruginea) and Bar-tailed Godwit (Limosa lapponica). Also, good numbers of Dunlins (Calidris alpina) are around.
Nabben and the Mäklappen beach, to the south-west corner of the peninsula, are two of the best places for birding in the area. There were lots of waders a few days ago, with an specially nice flock of about 150 Knots. I tried to make a video using my phone and the scope, here you can see the result.
We went out at night to catch them, together with Timmy, Emil and Erik. And we actually managed to catch some!!

We got 19 adult Dunlins (Calidris alpina). As far as I know, second year birds are possible to determine because of the worn flight feathers, small and droplet-shaped white on the tip of the primary coverts, and for the presence of inner juvenile-type median coverts, with tawny edges. For further and much more detailed information about Dunlins, I fully reccomend the website
Adult, 3+, (EURING 6).
Second year (EURING 5).
3+ on the left, second year on the right. Note the differences in wear and
colour edges of the upper tail coverts.
7 Red Knots (Calidris canutus) were trapped as well, a very nice species in hand. As some first winter birds can do a complete moult, and if there's no retained feathers, adults should be aged as 2+ (EURING 4).
With Curlew Sandpipers (Calidris ferruginea), and in ageing terms, it happens something similar with Knots. Seemingly, some 1w can undergo a complete moult in Africa. Thus, the bird we trapped this year (on the top), with 3+ (EURING 6) appearence, should be aged as a 2+ (EURING 4), at least until more research is done. Nonetheless, the bird I trapped last year (on the bottom) can now be safely aged as a second-year (EURING 5).

Also, this ferruginea can be sexed as a female. Males are richer coloured in underparts.

Is was a great surprise when we found this Bar-tailed Godwit (Limosa lapponica) in the nets. It was actually smaller than expected, but nicer!
It was a 3+ (EURING 6), second-years have very worn primaries, and usually they don't attain full summer plumage (Prater et al. 1977). Also, tail feathers are adult patterned, and the bird is a male; specially for the bright underparts.

Why are all this waders orangish in summer? I've been looking for some explanation, but I haven't found anything. As the colour is a deep orange, I guess the phaeomelanin will be the main component of it. I don't think carotenoids would be very related to this colouration...
Also, the tone is more or less the same in very different species, like Knots, Curlew Sandpipers and Godwits. Who knows...

The start of a new season

Another year, another season. I'm back to Faslterbo, where I'll be ringing for two months in the Flommen reedbed. It's already the third season for me here, but all of them are always different.

The first day of the season was specially good. We trapped 102 birds, but the big number was mainly because of the Swallows and Martins. We trapped 62 Sand Martins (Riparia riparia) and 12 Barn Swallows (Hirundo rustica), that were roosting on the reeds in the northern round. It was actually the second biggest catch of Sand Martins ever!!

When I came, Björn told me a dead Bearded Tit (Panurus biarmicus) had been found by the reedbed. It is still very early for migrating Panurus, so it was suggesting a possible breeding in Flommen. During the first day we trapped 2 youngsters, both males, and during the following days, we got 3 more: a total number of 4 juveniles (3 males and 1 female) and 1 adult female, so far.
First year (EURING 3) male.
Sexing juvenile Bearded Tits is rather easy. Female to the
left, male to the right.
Adult (EURING 4) female.
Not all are good news. After talks with different friends, it seems that the breeding season has been really bad for many species. Both May and June were very cold, and there's apparently less insects than other years, specially in the reeds. This feeling is actually noticeable in the ringing totals, cause almost 20% of the Warblers caught were juveniles, and there is apparently many less Reed Warblers (Acrocephalus scirpaceus) in the reedbed.

Indeed, if we don't count the hirundines, we are catching just a few birds. It will be really interesting how the season goes. At least we have trapped a bit of diversity..

First year Yellow Wagtail (Motacilla flava) in complete
juvenile plumage. It looked like a Pipit when I saw it
for first time!
First year Reed Bunting (Emberiza schoeniclus) in juvenile
plumage. They breed in Flommen!
Some are already doing the postnuptial moult...
While some are still very worn...
Like this one, a second year female! Yes, some very worn
females have complete black head and even greyish rump,
but the white collar is narrow, and the bib is not completely
black, just the malar stripes and some random feathers
in the middle.
 In the lighthouse, Caroline and Sophie trapped this young female European Green Woodpecker (Picus viridis viridis), a very nice catch, specially if we look at the totals: the last one was ringed in 1995, and is just the 5th ever!

 It really surprised me how dark and mottled was. I had only seen Iberian Green Woodpeckers (P.v.sharpei) before! Here is a comparation of both subspecies. Also, the one in the bottom is a male: note the red moustache.

We spent one afternoon in Knösen for the bird counts we got very nice views of about 200 Barnacle Geese (Branta leucopsis) feeding.

We are having some windy and rainy days lately, but I still have a very nice feeling for this season.

First sunrise of the new season

Saturday, July 25, 2015

Mediterranean forest

I've spend most of my life surrounded by mediterranean forests. It actually is the commonest habitat in Catalunya, and I would like to write a single post about it; specially since I started a constant effort ringing station in Montserrat, inland, and I'm gonna focuse the post in the habitats in the lowlands in central Catalunya.

Probably one of the most important factors you have to think about when you talk about this habitat is the fire. Many plant species are completely adapted to it, and it actually is part of the ecological dynamics. Thus, in a mediterranean forest you'll usually find succession communities. Potencially, a mature mediterranean forest in Catalonia would be a forest dominated by Evergreen Oaks (Quercus ilex), and quite dense undergrouth. Nonetheless, almost all forests you would see are dominated by Aleppo Pines (Pinus halepensis), which represents the first forest stage in a successive progression of this habitat. Actually, Quercus ilex grouw better in the shadow of another tree, cause when they are not enough large, Sun's radiation can affect them too much.
I will speak about two places where I've been working. The first one is in Montserrat mountain, an area that was burned in 1986.
As you can see, Pinus halepensis is the dominating species, with Arbutus unedo, Lonicera implexa, Smilax aspera and Rosmarinus officinalis mainly.

In this habitat, Western Subalpine Warblers (Sylvia inornata iberiae) and Sardinian Warblers (Sylvia melanocephala) are usually the commonest breeders.

This small Warblers are often difficult for trainee ringers, so the following lines are specially dedicated to them.

Ageing Western Subalpine Warblers deserve, surely, more explanation. Still, I'll post a couple of pictures:
Second year (EURING 5), male.
Adult (EURING 6), male, already doing the postbreeding
moult in early July.
Western Subalpine Warbler (Sylvia inornata iberiae).
Male to the left, female to the right. Both are second years.
Sexing Subalpine Warblers is usually easy, like in the picture above. Nonetheless, some females can be quite similar to males, but they have mainly orangish tones in underparts, and the coloured area is more restricted.

The main trouble for trainee ringers, but, is the identification of first years in juvenile plumage. As both species are quite common, and as their chicks become fledgings more or less at the same time, it is actually easy to catch them. It is easy to find them in complete juvenile plumage from late May to early July.
Sardinian Warbler (Sylvia melanocephala)
Western Subalpine Warbler (Sylvia inornata iberiae)
Appart from the differences in shape, specially in the head, and wing formula between both species, juvenile inornata have browner borders in greater coverts, tertials and secondaries, which are usually easily seen even in the field. Juvenile melanocephala is usually gryer and darker, while the grey in juvenile Subalpine is paler. Underparts are also cleaner in Subalpine.
Another thing to check: tail patten. The outer rectrices in
Sardinian (left) are whiter, both inner and outer webs, and
the tip of R5 and usually R4 are pale. In Subalpine (right),
the outer rectrice is white specially along the outer web, and
the inner is faintly white. Also, feathers are darker and greyer
in Sardinian.
Both Subalpine and Sardinian are present in almost all the stages of recovery of the potential habitat, and also in the mature forests. Other species' presence depends more on the stage; scrubland, small trees, medium to some large trees, etc. The place in Montserrat, Can Maçana, was burned 29 years ago. The medium sized Pine forest, with abundant and rather dense undergrouth, and the Rosmarinus officinalis scrublands in the most exposed areas, make a divers habitat for birds. So, some typical scrubland birds can still be found, in low densities, like Dartfords Warbler (Sylvia undata). Melodious Warbler (Hippolais polyglotta) usually appear when there are big bushes and first trees appear, which are usually Pubescent Oaks (Quercus pubescens / humilis), specially in N sides. Many forestal species can appear already. Western Bonelli's Warbler (Phylloscopus bonelli) and Firecrests (Regulus ignicapilla) are usually found were trees are still small, while Nightingale (Luscinia megarhynchos) and Blackcap (Sylvia atricapilla), for instance, appear when the trees are taller and the undergrowth also is taller (because of the shadow of the trees).
Melodious Warbler (Hippolais polyglotta)
Western Bonelli's Warbler (Phylloscopus bonelli)
Firecrest (Regulus ignicapilla)
As trees grow, and the habitat grow in vegetation diversity, other species appear. Following the sequence, Winter Wrens (Troglodytes troglodytes), Great, Blue and Crested Tits (Parus major; Cyanistes caeruleus; Lophophanes cristatus) and Short-toed Treecreepers (Certhia brachydactyla) colonize the habitat.

Winter Wren (Troglodytes troglodytes), adult (EURING 6) 
Winter Wren, first year (EURING 3)
Short-toed Treecreeper (Certhia brachydactyla), first year
Blue Tit (Cyanistes caeruleus), adult (EURING 6) female
Crested Tit (Lophophanes cristatus), adult (EURING 6)
Common Nightingales (Luscinia megarhynchos) arrive in breeding sites during April, and by the end of June they are already doing the complete moult. As soon as chicks are independent, sometimes even before, the first primary is dropped, being probably the fastest complete postnuptial moult in the area.

Blackcaps (Sylvia atricapilla) and, sometimes, Garden Warblers (Sylvia borin) can also appear. Both are related to north orientated sides, and specially close to small rivers or in dry ravines.

Talamanca is a small village north east of Montserrat. There was a big fire 10 years ago, and because of this, it has been a very interesting place for local birding.

As I was saying before, N sides grow faster. In this bushland communities, mainly Arbutus unedo and Rosmarinus officinalis, and with Quercus pubescens, is the place where you cand find other interesting species, like...
Western Orphean Warbler (Sylvia hortensis), adult
(EURING 6), female.
There are lots of rock natural walls, which together with the open areas, make the perfect habitat for Blue Rock Thrush (Monticola solitarius) and Black-eared Wheatears (Oenanthe hispanica).

Ageing Black-eared Wheatears is very similar to Northern Wheatears:

Adult (EURING 6), male.
Second year (EURING 5), male.
Adult (EURING 6), female.
Before the fire, the a Black Pine (Pinus nigra) forest was found in this place. Now just a few trees remain, but the change of the habitat, despite the fire, was not that bad. Fire is definetely important in the mediterranean ecosystem.