Thursday, 22 September 2016

The second set of secondaries.


continuing the theme of subspecies, morphs and all that malarkey, I thought I'd introduce another factor that could make your birding experience evermore exciting!

Everyone likes Shrikes; they have stunning plumes and an unusual habit of hoarding their prey; they're relatively easy to identify too - or are they?

While out in Norway we managed to chance upon three Great Grey Shrikes, an adult and two 1st years. Unfortunately I lost the pictures of the adult bird but am still able to study the other two birds in detail. I managed to ring both an adult and juvenile and feel extremely lucky to do so, thanks to Nigel and the team's kindness.

Anyway the first juvenile we caught was a typical ssp excubitor, exhibiting diagnostic tail pattern and limited white in secondaries along with the typically darker/colder feel. Bear in mind the photos I am attaching have not been edited in order to give better appreciation of tones rather than making it look nicer; that's science!
Note black shafts in outer tail feather and black extending halfway down the second outermost tail feathers. At the time I forgot to ask for Nigel to spread the wings to get a photo of the rump since it is an identification feature; white is suggestive of homeyeri (the eastern race from Black Sea west to Siberia); grey is suggestive of excubitor (our most common race). It would be good of me  to source imaging of genetically identified bird's tails, however I think it's best for you - if you're as keen as me on the topic. 
In this photo the important feature is to recognise the scarcity of white in the secondaries (that feather group being the the three white 'teeth' to the middle left of the wing then left of that are the rest). In a typical homeyeri you should see a large white patch similar to the primaries creating a large white wing bar effect. However, with many subspecific groups, intergrades should be taken into consideration with some showing intermediate characteristics relating to their birth (most likely) being between the allegedly clear-cut groups. 
I used this photo for to pick up jizz and general feel of the bird, which is most important for those of you that bird rather than ring. Although the photo is slightly over exposed you should make out the dusky grey plumage with the white patch in the primaries being forefront, while the secondary patch is barely visible. I may add that the most diagnostic feature is tail and is diagnostic; things such as secondaries, grey colour and rump are only pointers. Secondaries are useful for telling if they're intergrades rather than true subspecies, unless it's some sort of galliae' type bird. 

This picture is of no scientific note (more insanely satisfying, look at that bill!), however it shows the buffier, more diffused pattern that you'd expect with a juvenile bird. 

Right so here's the catch. Finally Biff :P The final Great Grey Shrike (I like that line proves we caught more than one: wow) was of more interest and instantly grabbed my attention both when it nearly ripped my finger off in the net but also because of its wing. 

Here is the bird:

Now what should 'grab' you is the 2 large white patches; fundamentally the uppermost one since these are the secondaries. Now if you compare it to the original bird. 
See what I mean now? Furthermore, in retrospect, it also appears paler even though the shot of the previous bird is considerably overexposed. It also presents a nice WHITE rump; all these fatures are leading to one answer, aren't they? Homeyeri. So why don't we check the most important feature, the tail.
NO! The tail is clearly the same as the previous bird's; take a look:
Exactly the same. So what now? You ask. 

Well here's the interesting part - for me at least - and for those who have managed to read this marathon. Hitherto I hadn't realised birds such as this existed I therefore RTFB as the group said AKA read the F****ng book! I was enlightened to hear of a form (not subspecies remember) called 'galliae". This bird is supposedly known to posses large amounts of white in the wing(secondaries in particular) yet still have excubitor tail pattern. Wow, we're getting somewhere here. Now, now though, I haven't got any experience with these (and whether they're a thing is debatable) and there appears to be a lack of text on this subject, therefore I would tentatively leave it as possible; for if you were to be so confident you'd only be let down - well at least that's my experience. 

Here's the wing for those like me, itching to see it. 
Loads of white again in the secondaries but again look at that white rump. This picture is far more representative too since it isn't overexposed like previous shots. First bird for comparison again.
Only tiny little teeth in the secondaries. 

After reviewing (just this minute while typing up now) I would also like to highlight moult. The first bird is already moulting suggesting it is an older bird; bred earlier on this year. Now if you have any experience with eastern taxa in ornithology, it is a common occurrence for eastern birds (like Caspian Gull) to moult quicker linking to seasons. Now like me you may at first take this with a pinch of salt, however I think it could be something to bare in mind, even though it could just be because it was simply an earlier brood.

AHHH... So there you have it, hope you managed to take it all in; I'm struggling at this end mind! 

Saturday, 10 September 2016

Hoary for me. The Redpoll chronicles.


By the end of the trip our hopes of catching a "snowball" deteriorated; we were particularly interested in catching one for identification purposes in case one turns up in Wiltshire - as my wise uncle once said, it would be as rare as rocking horse poo. Furthermore, before catching this bird we queried whether Mealy Redpolls had hybridised with the Arctics causing there to be a handful left, especially considering many of the birds caught beforehand shared a few pro-exilipes features and even cabaret!

I would like to take credit for the capture of this female by correctly describing it (and photographing it)
 then nudging it towards the nets: all for science!

Now in the hand we could study the bird down to minute detail. Nigel - the man with the onus of looking after Matt & I but has by far the most experience with Redpolls - began the identification process by checking its under tail coverts (utc):
As you can tell this bird's utcs are bob on: pure white with no dark shafts AT ALL. 
Here's a picture of the bird's utcs being compared to Svensson (the bible of bird ringing). 

Nigel then went to the rump:
Have a look at that; just like the utc this bird's rump was top draw. Ooooo... How much I'd like to see this in the UK. 

So what are we looking for? Like most of the this Redpoll drivel there's no exact science, yet a very white rump extending way up the birds back is ideal. Some say there's a measurement across the bird's rump can seperate it from Mealy; I'd be very tentative in accepting this thesis. The last photo should help you narrow down what age/sex this species should be. 

The question is, does it fit the bill? Both metaphorically and physically!
Of course it does! Even though the bill does look rather pointed/elongated it is well in the realms of variation, being short and deep-based. Another minor point of note are the nasal hairs that go rather far down the upper mandible, giving this sheath effect. 
One feature Nigel inputted that was of particular interest, among innumerable other things, were the leg feathers. 
One valid suggestion would be to rename it the Rough-Legged Redpoll, has a nice ring to it. At first this may not mean a lot to you since I don't know many birders staring at the Redpoll's legs. However, if you compare it to a Mealy Redpoll:
I think it's pretty self-explanatory. It also supports Darwin's theory as a side note; natural selection causing birds with more insulation to live longer and reproduce. So if you ever see a booted/rough-legged Redpoll you could be onto something. 

So now we know it's a supposed "Coues' Arctic Redpoll" what age and sex is it? Let's start with ageing. 
Tail feathers (tfs) and wing feathers (wfs) fresh and no moult break in greater coverts. Juveniles should be going through a complete now so old feathers should be being replaced by new ones and difference in colour and wear should be obvious. 

Now to sexing: Clear white rump, lack of pink in the chest eliminates possibility of a male. So there you have it: an adult female Coues' Arctic Redpoll, ladies and gentleman. 

If only it was that simple. If you have a look in the old trusty Collin's field guide and go to page 379; you should notice an illustration of a very white Redpoll with no sign of buff to the tips of the greater coverts. That description clearly doesn't fit with this bird. That's not to say the book's wrong but is showing a classic clear-cut individual, it's never that simple is it? What I'm saying is that there's far more variation than one might expect (like I did beforehand). I'm also suggesting to look more carefully at that whiter redpoll you find in the winter and not disregard simply because it isn't the snowball you might first presume. 

The question I'm waiting to be definitively answered is whether Arctic and Mealy hybridise, there's a PhD - that no one will fund you for! Did Arctic Redpoll become genetically distinct enough to prevent interbreeding (and the formation of a fertile offspring) before global warming caused a shift in the Mealy Redpoll north? All very interesting stuff, so interesting I'm planning to write my EPQ on it. Watch this space!

Friday, 9 September 2016

Juvenile Arctic Redpoll - where's the beef?


after going on a recent expedition to Arctic Norway I was exposed to (what was unbeknownst to me) the Redpoll issue. Here in the UK I get the inkling  (ignore my generalising just an impression) that many folk are splitting these Redpoll into categories that don't really exist - I for one was one of them.

To begin with (I hope to write further posts on this subjective topic) I would like to give you a taster of what I mean. Could you enlighten me on the identification of this bird?

Before going to Norway and having to study each Redpoll as if it was a new species, I would instantly rule out Arctic (it's too brown we've been told all along)! I would then focus on Mealy and Lesser. Now I hope you noticed the bill; supposedly Mealy have the largest/longest bill; this clearly has a tiny one. So there you have it a Lesser Redpoll but wait hang on a sec we're 400 miles north of the Arctic Circle so geographically it CAN'T be a Lesser. It also has only 1 dark shaft in one of its under tail coverts and it has a white rump. Hang on then, what is this telling us? We've got a bird that is meant to have the longest bill of its family yet acquires the smallest one I have seen. Get where I'm going here? 

There you have it. This whole Redpoll malarkey is all gobbledygook - yes I know we all know that, which makes this so interesting. Let's not stop here, however and try to get to the end of this mysterious juvenile bird. For me structurally (and in a few places plumage wise) this instantly gave me an Arctic Redpoll impression. I'll run through the pros: small bill, rounded, tiny head, densely feather legs, white rump and only 1 dark tail shaft. Bearing this in mind I quickly went to the web in search of a photo and/or even better description of exilipes in juvenile plumage. What did I find? Nothing. What gets me is how we can describe this as a distinct species when there's no text describing them (at least to my knowledge)! 

What I keep getting the vibes of is this being the same situation as Chiffchaffs: clinal. Collybita-trisits, cabaret-exilipes. My fellow far more experienced ringers also discussed further that night (and throughout the holiday) about this bird and Redpolls, we all came to the same educated conclusion: lump them. Of course this isn't an exact science and we still are by no means definitive but I'll leave this question for you. To lump or not to lump? That is the question.

Saturday, 3 September 2016

The Chiffchaff chronicles. An attempt at clarity: my perspective.

for what seems like an eternity Chiffchaffs (Phylloscopus Collybita) - the mother of all LBJ's (little brown job's) - have been under the microscope. This is not because of the species pair Willow Warbler (Phylloscopus Trochilus) causing confusion. It's the infraspecific differences within the species that is causing the uncertainty. In this (sort of) essay I will include my photographs, my thoughts but will incorporate secondary sources to support my thinking of this tricky Chiffy situation.


I will first begin by going through the ins and outs of our own subspecies of Chiffchaff: Phylloscopus Collybita Collybita. This subspecies distribution extends from the UK east to Bulgaria and Poland. Recently it's range has increase northwards nearly into Albietinus territory, Scandinavia. These are most commonly found in the summer, with a large proportion migrating from Africa in the winter to spend the spring and summer breeding in the UK. Recently (possibly due to the milder winters) more and more are becoming lazy, residing here in the UK over winter, generally around sewerage works. Up to 5000 - probably more - are wintering according to the latest counts. Which is where the tricky Chiffy situation unfolds... More on that later.
Classic Collybita type. Mantle, head and cheeks show olive wash with slightly paler bill than other ssp. Also note light tinge to supercillium unlike darker, buffier, EASTERN races. Furthermore yellow-greenish (flank) shown beneath wing which is another key.
Mantle: Collybita types have an olive green mantle. Ranging from a dull green to the brighter juvenile plumage which is yellow-greenish.
The purpose of this shot is to appreciate the colouration of the mantle and wings. The concolourus olive shade is equal throughout bird's back, even stretching to lesser and median wing-coverts along with the alula. Again typical.
Legs/ bare parts: They have dark legs with more of a brownish tinge than pure black. Their bill is generally plaer than Siberian Chiffchaff with more of a clear appearance in the field, however is not a clincher/go to identification key in the field because of it's variability. 

Flanks: subdued yellow tone extending from legs then encircles them to below the cheeks.
Here you can see two Collybita types at different positions. Attributes almost identical but clearly shows on left hand bird that the olive colouration extends to rump as well.
Facial appearance: pale cheeks with weak, yet clear yellow supercillium. Head has same olive tone as mantle that could be seen as slightly darker depending on view.
Same birds as above but this time possibly better for alternative identification; left hand bird showing yellow hue all over  body, not just in flanks which makes the job a lot opposed to a paler Collybita type.
Call: Now this is the clincher generally for identification opposed to other Chiffs. I'd describe it as a gentle weep sound, that smoothly gets higher in the short call. Calls can't be put into words to here's a link of a collybita type.

Now for the tricky part. I will try to provide information and some photos of quintessential Tritis types that I have seen/found. But first of all, where do these birds come from? Supposedly these birds represent the far east of the Chiffchaff's range, hence Siberian, breeding east of the Pechora river and wintering in the Himalayas, while passage migrants are typically seen passing through Kazakhstan, Israel and many other eastern states. Every year several of these birds are found (normally by call) all over Britain, including inland counties which is what makes this subspecies so exciting for many. The vast majority picked out at sewage works amongst Collybita types. Sightings of these birds across the UK have been increasing annually possibly due to increased coverage and understanding over identification write ups. However, many still believe some are being picked out wrongly which is causing a major dilemma for county records nationwide, here's my attempt of resolving that issue, to you "lucky" few reading! 

Mantle: One of the first things that makes classic Tristis types stand out is the cold grey back, instantly grabbing your attention and making you wonder about the possibilities. However, as many people have suggested in the past lighting is a huge affecter on profile. In dark light generally a cold grey colour comes through but can occasionally give drab brown/grey tint, nonetheless still ultimately has some grey on show. In bright light they tend to show ice grey cast which birders generally look for when contemplating over one. However, (as I'd describe) warm light e.g. dusk or dawn the brownish pigment is more apparent out of any light condition. So is therefore something to take in mind if looking at a differing Chiff. A few sometimes posses some odd olive feathers but generally offer western subspecies genotype so: Albietinus, Fulvescens, or to be even more bewildering Tristis x Albietinus
Thankfully I recently found a Tristis type down Kenidjack Valley, Cornwall which allowed me to amass appropriate shots for an identification platform. The bird exhibits its diagnostic cold grey mantle extending up neck to head. However, if you look closely you could possibly a brownish cast within the grey which is still recognised as normal for the species as declared above. A further feature is the bare buff, if not white white flanks completely different to the olive/yellow sides of a Collybita type.
Leg/bare parts: Legs are by and large black and set side by side with a Collybita type are only just noticeably different. Legs are best to look at when light because Collybita's brownish/ochre hue is normally brought out by sunlight while Tristis stay black. I picked up that the feet are are very variable in both types so not worth too much time on. Typically bill is darker around the gape of it opposed to Collybita but good views need to be acquired before jumping to conclusions.
Same bird. The pose pictured gives indicative features of what to look out for. First of all the mantle,  it has a grey/brown that runs into the scapulars, lessers and partially into greater coverts. Furthermore, the grey hue albeit browner reaches cap, also notice buff cheeks and inconspicuous sandy coloured supercillium. For me the contrasting olive primaries and secondaries give a different and more profound look compared to Collybita who's olive mantle gently smooths into similarly coloured wings. Last point of note white clean flanks with only pallid tones near cheek. 

Flanks: These birds how no colouring on flanks if not a faint buffish far sandier/earthier impression compared to Collybita. A very handy ID feature when taking notes.
Yet again same bird. encore, buff cheeks, faint supericllium, grey/brown mantle and cap, indistinct flanks with just off-white tint and significantly conflicting pigments between wing and mantle. All these features to separate Collybita.
Facial appearance: In parallel with the mantle Siberian Chiffchaff's have a unique face which should definitely be entertained immediately upon finding the bird for physical characteristics. They have buff-grey wash cap, a lighter more buff cheek and a buff to white supercillium sporadically some birds as above have hint of yellow near front of supercillium. I would also say Siberian's have a noticeabale neck ring which nearly forms behind head. This neck ring I'd describe as a paler, colder grey which can be apparent from certain positions.
I used this picture entirely for the purpose of shade differentiation depending on light intensity. Now this bird's mantle seems to present a brighter hue which is more brown, even partially olive in some ways. Nonetheless, this bird still possesses features to counteract that view: Buff cheeks, pale supercillium, colourless flanks and dull brown cap.

Call: Linking back to what I said for call in Collybita types, this is the determining feature for identification so knowledge of call is pivotal when out in the field or else good recording equipment at hand to compare or ask for expert's opinion. Link to classic call:

Very similar to other photos so no need to elaborate, but can help you now try and pick out what this bird has which makes it of eastern descent. There are 6 different things for me here which make it Tristis try list them, there'll be more though I'm sure!

Rather shoddy photo and position of bird, although enables comparison between two subspecies. Tristis in background and Collybita fore. Are you able to pick out the Collybita's yellow washed breast and dull green hue to mantle even if shot's not up to scratch?

Eastern Chiffchaffs

 Prewarning: I have labeled this heading as Eastern not Albietinus, Fulvescens, Brevirostris etc. For one reason that I'll explain at the end. 

While ringing the team and I have seen three Chiffchaffs which so plumage characteristics similar to Tristis and the supposed Albietinus/Fulvescens but aren't clear cut enough to name because of their "call-less" nature. Nevertheless they do show very similar features that are of note so will try and explain the thinking behind them being Eastern and why we weren't able to assign them to ssp.

Bird no. 1: Swindon STW, 22nd November 2014

While attempting to catch Redwing on migration in Swindon we (Matt, Paul and I) had the pleasure of catching a couple of Chiffchaffs as a billy bonus. Matt had spoke of seeing an eastern looking Chiffchaff but wasn't ready to call on ssp. Miraculously this bird landed in our nets for close inspection but as per usual we were still none the wiser! It refrained from calling leaving us the unfortunate, discouraging situation where we had to leave it as "Eastern". Here are the pictures:
This bird strikes me instantly as a Tristis, remember the features? cold grey mantle, buff supercillium, dark bill, clear contrast between wing and mantle, flanks clean with slight buff wash, pallid cheeks and (my id feature) paler grey neck collar. 

So not much wrong with the bird if anything, possible hint of olive near "shoulder joint" but other than that a good shout. So the only thing not going for it was the call and these birds without the call unfortunately have to pass as probable. Nonetheless, don't be disheartened many Tristis types have good site fidelity and once found should stick in the vicinity for the whole winter, so persistence is key!
Mantle again A1. But after close inspection some partial olive flickers within the grey mantle make it slightly less credible. Forcing me to conclude: eastern type. 
Just for further corroboration and analysis... The light in this angles makes neck collar even more pronounced, far paler than any other part. The darkness also causes olive traces to be invisible which is highly likely a causer of many birds to be misinterpreted. 
A view (for obvious reasons) not attained in the field but shows armpit hair (!) is yellow as a matter of fact! At least they don''t show this in the field make matters yet more problematic. Flanks are still buffish though and head distinctive.
Bird no. 2 Marlborough STW, 27th February 2015

The morning we caught this bird another suspicious looking one bundled into our nets, however was released accidentally before review. This bird for me was more of a western bird, or central Europe, for its pale shades were localised and patchy on mantle. Thankfully my ringer has had first hand experience with genuine Siberian Chiffchaffs in Kazakhstan (over 400!) so when he's company there's no going wrong with identification. No call once more but views in hand are the best of course so we could study it closely. Here are some pics:
 As you can see the bird's characteristics are very intermediate between Tristis and Collybita this lead my trainer to the Albietinus side. LIke I said, very patchy grey on mantle, subdued yellow, more colour in bill than normal (for Tristis). Linking back to my identification feature neck collar on this a pale lemony yellow with hint of grey here and there,

Another perspective, this time shows a somewhat pallid buff cheek, greyer cap and more of a buffish flank near shoulder of wing. All very strenuous but we'll get there! 

Bird 3, Kenidjack Valley, 29th-31st December 2015

My most recent bird to complete the trio and for me the most interesting. As you can see it's a ringed bird leading me to think (for no compelling reason) that it's a British raced Chiffchaff AKA Collybita type. On the first day I saw this bird I discarded it as just an unusually brown bird. But father research later that evening on eastern type got me intrigued... First of all you can see the neck collar had faint grey feather on the tips of the old feather. Furthermore the colour is far too brown to be in the realms of any Collybita. This left me bamboozled because this bird is a) too brown for a Tristis and b) too brown for a Collybita, so what on earth is it? Well the closest match I could find was on this website of birds passing through Israel:
As you can see this bird is far too brown above for a Tristis and also lacks great big buff supercillum which is to be expected. But all these features don't seem to lie in those of a Collybita type, leaving many to of for Albietinus. But I have no time for Albietinus and Fulvescens and believe their true origin is a mix between the true separate species of a Siberian and Collybita type Chiffchaff. Therefore Collybita x Tristis
Another shot this time showing my id feature for Tristis, the neck collar encompassing the back of the head. However the shade is still very brown so unlike any other ssp.

Here's my bird that I was studying. Two features which I think differ from the Israeli bird and this one is the ochre/tobacco cheek of my one and feather more mottled neck collar compared to Israeli bird.
The cheek is obscured in this photo but mantle is a clearly brown with a hint of olive in the wing panel. Its head is even browner on top which is unique, apart from the Mountain Chiffchaff.
Here you can see the tobacco cheek and other supporting features.
Albeit slightly out of focus, I find this shot the most interesting out of the lot. Small buff supercillium present but too small for Tristis, sandy brown looking back now and prominent grey neck collar. Also notice buff flanks, characteristic of Tristis

Another ringed bird I saw on the next but not well enough to confirm as the day started calling and managed to record it, this is definitely a Collybita sound, making it all that more confusing! 

That's it for now I will try to explore further in future posts...

Tuesday, 12 January 2016

Bird ringing, Savernake, Sunday 10th January 2016

Sunday was one of those fantastic days you don't want to end. The team consisted of Matt (of course), Anna, Paul, Noah, his Dad, Tim and Graham.

Setting up took no time, efficiently putting up nets down the net rides that were cleared by Matt and I in preparation for today. Half an hour later then euphoria happened, Woodcock! This is a dream bird, so to ring and hold it would be absurd and absurd it was...

 We aged this bird as a 5 (born last year) and assume that it has come from the continent, most likely Scandinavia/Russia believe it or not.  This is because satellite tagging by the Woodcock project proves many are continental migrants. It weighed just over 300 grams but most incredibly I got the wing measurement spot on!
Yep I'm a skinny whippersnapper, trust me those Wellies do fit! 
Every time it wing stretched I couldn't keep its wings in position; Woodcock's are very powerful hence where they travel from and what traits they need. Nevertheless its cryptic camouflage stole the show again, simply stunning.

Our next showstopper(s) were the Redpolls, 14 of them attracted to the tape. A large proportion were adults (sixes) which could lead some to believe they had a poor breeding season. However, Matt and Graham said sometimes birds travel in flocks depending on age, I hope this is the case, further catches will prove/disprove this hypothesis. 

On any other day these birds would have been highlight by a mile but the Woodcock was sublime. Nonetheless Bramblings mesmerize me, particularly the males therefore catching 11 birds was brilliant. Matt has had a control (recapture of a bird not from this group that has a ring) from Norway! Data like this is brilliant so I'd be overjoyed to see one of these find their way over the North Sea into a Norwegian net; its contribution to science would be invaluable!

Pictured above is a dazzling male, showing off its orange ambience. Matt predicts this flock will grow till a peak around February/March of possibly up to a 100. Now wouldn't that be something?

 The female attempted to resemble the male but its flashes just aren't bright enough, aren't we men flamboyant, albeit clumsy (that applying to me) and less organised! I still believe the female presents a unique charm and possesses beautiful lemon armpits as does the male.
 The paparazzi were hot in this lad's tail but he seemed content perching on Matt's hand.

Another noticeable feature of Sunday's theme were the hats:

We all had are wooly hats undergoing extreme cool temperatures (5C)! Hopefully the next few weeks will provide us with out much needed winter weather...