Saturday, 25 December 2010

What A Load of Bull !

Following on from the post several days ago I have now got some pics, audio and revelations to share about 'unusual' Bullfinches....or perhaps just 'Bullfinches'. Might be worth reading Mark Lewis' recent post on his 'funny' Bullfinch as well.

It is worth re-iterating here that not ALL Northern Bullfinches give trumpet calls - there is another type that sounds very like our British sub-species pileata.

Okay, here goes, lots of pics, sonograms and audio ( a first for Loxia Fantastica) !

Wednesday 22 December 2010

We managed to find 3 Bullfinches feeding on nettles at the same location a the previous day. They were all males, including this 1st Winter bird:


The photograph shows it has only replaced an innermost greater covert ( grey-white tipped contrasting with buffy tipped ones). Interestingly, like the bird yesterday ( most likey an adult following reappraisal) this specimen also has a white edge to P9 (outermost large) and the other adjacent PP are edged white below the emarginations. Notice that is has the 'stuck on' beak rather than the 'howker' that Northern birds would have ( however, the bird is puffed up which could diminish the proporations of the mandibles). There is a pale line beneath the eye.

Also present was this larger, bright male:


The alula looks like it might have grey-white edging so possibly and adult. The outer-most greater coverts, although not extensive in their white-grey tips, nevertheless appear more adult than short, buff  juvenile ones ? Like the juvenile above, this specimen also has the white edging (quite extensive) to P9 and the adjacent inner PP are also white edged on the emarginations:


And here too:



That outer greater covert looks a bit dodgy in this pic ( but still too extensively grey-white tipped - possibly a retained adult feather ?). Alula looks very brown here as well - again adult retained or possibly juvenile ? If it is a 1st winter bird it has undergone an extensive post-juvenile moult (unlike the first bird above). Based on this and these other features I'm sticking with adult. Pale line under the eye with this one too - is this as a result of the feather tracts being displaced by the bird puffing up ? Mark's last post mentions primary projections - not sure how consistent that would be in the field but possibly useful enough to distiguish between pileata and pyrrhula combined when with other factors. On that basis, these two have short primary projections consistent with pileata.

The birds were not very vocal but I did manage to get some recordings (with Sennheiser ME67 and Fostex FR2). This recording has "tip" contact calls ( often given in flight or pre-flight), some "pee-u" calls and near the end a "buzzy" toot call ( not like Northern, but similarish):

A14h18m30s22dec2010y by Loxiafan

A sonogram of the muted contact calls and a typical (?) pileata "pee-u" (timings don't necessarily match the events on the recordings):




Notice the strange component under the main descending note ?

From the same recording here is the muted contact call followed by a single buzzy whistle note ( appearing as a horizontal line on the sonogram below):




The other decent recording I got had pileata type contact calls:

A14h32m15s22dec2010y by Loxiafan

On the sonogram these appeared to be two elements super-imposed over each other, but nevertheless giving the pileata descending structure:




So, a summary of birds seen this day (3 males):

All three had white edged primaries.
All had "stuck on" bills.
None had white on tail.
None gave 'trumpet' calls, or it seems the other 'Northern' type call ( which is similar to pileata but lower piched and more 'mournful' sounding - think Chaffinch v. Willow Warbler).

= none were pyrrhula !

The Pennington/Meek BB article is quite right to highlight some of these shared traits between pileata and pyrrhula, and what might otherwise on first reading seem like a conservative possibly non-commital paper actually turns out to be a very well researched, useful and accurate essay on the type. Get it if you don't already have it.

The big question is: was one of these birds from today the big 'tooting' male we saw on Tuesday ? Well, read on...

Thursday 23rd December

This started off with good intentions by taking the Remembird (except it switched itself off, without me knowing so no recordings - amatuerish, I know). Found 3 males at a different location and was able to ID the juvenile male as the same one as yesterday ( due to a plumage feature on the flank). These birds allowed me to get withing 4 feet of them feeding on nettles - very confiding, or just very cold and hungry to otherwise give a damn ?


Friday 24th December

After yesterday's er... equipment failure time for the nuclear option: Telinga Stereo DAT and FR2LE, the major crossbill gear. We found three birds at the same location I had them yesterday, but this time there was a juv female in tow with two males, so not the same 3 but possibly two of them.

Things started of promisingly, the juv begging for food and then these "sotto voce" toot calls (at 6 seconds on recording):

B14h52m37s24dec2010a by Loxiafan

On the sonogram these appear as horizontal flat lines, have harmonics but unfortunately don't sound like Northern trumpet calls, being higher pitched and different in timbre:




Could these be the same sotto voce tooty "honking" calls we heard from the bird on Tuesday ? Possibly. Are these calls being heard by other observers and being confused for Northern trumpeters ? I don't know, but possibly.

However, the big male then called and this was pileata-like, but didn't sound quite right - on the sonogram directly underneath you can see the component under the main element, and again this call has harmonics un-like those presented and described in the Sound Approach for 'British':

B14h52m37s24dec2010b by Loxiafan



Notice that the first call (on sonagram) sounds slightly nore 'mournful' but the other two are shorter and deeper in pitch.

The group also gave "tip" flight calls:

B14h54m09s24dec2010 by Loxiafan


Also some pileata type calls, softer in timbre:

B15h08m24s24dec2010 by Loxiafan




Nice of a passer-by to let me know I was recording Bullfinches....I'd never have known. Thanks !

And this (also from above recording) a more exagerated call, and check those mini harmonic structures within the call (click to enlarge) :



One of the males gave this call:

B15h10m39s24dec2010 by Loxiafan




Notice that these are again double element calls, and have very strong harmonics. Is this normal in pileata ?

The adult male gave these same calls:

B15h13m32s24dec2010 by Loxiafan




Again, these have double elements (which make the call sound flutey) and the harmonics also give it a hollow timbre. These do not sound like any of the various Bullfinch calls I have been listening to on-line and on the CD's I have. I am not claiming it is a new type, merely commenting on the apparent variation that seems evident here.

So, where does this leave us all ? Well, for me, wishing I was out recording some crossbills ! Funnily enough I was surprised by how many of the Bullfinch calls were crossbill-like !There seems a lot of variation in Bullfinch calls considering I am recording a very small population within a stones throw of my house.  I am >95% certain the Bullfinches I have observed and recorded over the last few days are British pileata types. The large male on Tuesday gave a call similar to those B1452 above - it was the only call we heard it give and it was very different from the bird "pee-u" ing next to it. With no recording of it to reference it is not a leap of imagination to deduce that on recall (from memory) it could be confused with those Northern trumpet calls, as it appeared to "toot" - I initially thought our bird on Tuesday sounded like the second type on CD2 track 95 of Sound Approach. Listening to a recording these sotto voce toot calls, assuming they are the same as the ones we heard (and didn't record), sound closer to the "second type" calls on the SA CD2 - track 98 but are quite different in timbre and pitch.

To sum up "All that glitters is not gold" and "All that 'toots' is not (necessarily) Northern" !

Would definitely appreciate feedback and comments and if anyone has heard British Bullfinch give these sotto voce toots or double-element variations to the main call. The former call seems intermittent though the bird above today gave several repetitions of the call. Could this call be being confused by other birders at trumpeters ? Given the 'overlap' of other features this may be a concern. Are they normal calls for pileata ?
It seems getting good field audio recordings may become a requirement for rarities commitees when considering Northern Bullfinch.......

.....I am glad I was conservative in my diagnosis on Tuesday !

Meantime, I think I'll stick to Crossbill vocalizations !

Merry Christmas to Everyone, hope it's a good one !

© Lindsay Cargill 2010




Tuesday, 21 December 2010

Northern Exposure and Northern Bullfinch ?

The very bad recent snow has, just like last year, considerably hampered Crossbill activities so birding has been confined to whatever is withinin walking distance of the house. My last couple of local walks have produced several Bullfinches and Bramblings which is always nice in the absence of Waxwings (or Crossbills).

Today on the Old Deeside Railway Line by our house we had a male Bullfinch (British) pileata type "pee-u"-ing and feeding on dead nettles. Further along a female Brambling was associating with Chaffinches near to someones garden feeders (why do they go to someone elses feeders and not mine ? !). A walk through Allenvale Cemetery produced not at lot other than Common Buzzard being mobbed by gulls and crows.

We decided to go home back down the railway line and I am glad we did. WARNING ! - there are some photos to follow and I must add that they are not great quality having been shot in poor light with a consumer compact, however, they do show the diagnostic features that I would like to discuss.

The first bird we saw on the way back was another small pileata British type male Bullfinch with a narrow wing bars and giving the soft Brit "pee-u" call. However, it was associating with this striking male, and the first thing that alerted me something was different was the size, very obvious seeing the two birds together - this male appeared massive compared to the male that was feeding nearby. I would liken it to a Common Crossbill v. Parrot Crossbill eg. a significant size difference. Here is the 'big' male:



All photos are as they came out of the camera - no contrast or colour editing has been carried out only a slight unsharp mask. This bird is clearly a 1st winter male - juvenile 'brownish' primary coverts and alula can be seen in the photo.The other thing that was noticeable in the field, and can be seen in the photo, was the fairly wide white wing bars on greater coverts, and that these were 'saw-toothed', as well as pinky breast and pale grey upperparts and white that extended well up on to the belly and a very white and extensive rump, all good indicators of Northern Bullfinch. The black 'cap' also appears not to extend so far back on to the nape, and consequently the grey nape appears more extensive. I am not sure if this is a feature of Northern Bullfinch but Mark Lewis photographed a bird that looks identical to our one at Girdleness - could it even be the same individual ? ! :


                                                                    © MarkLewis 2010


A much better photo than ours - hope it's okay 'borrowing' it Mark ! Possibly our one doesn't have quite as 'saw-toothed' greater coverts and there is a deeper black chin bib on ours, but the 'cap' looks the same and Mark's also looks like a 1st Winter male. Ours maybe has more grey around nape, though this could just be the angle ?

On getting home I dug out the comprehensive article on Northern Bullfinch invasion 2004 by Pennington and Meek and sat down to look at the photos that we had. For those that don't have the Pennington and Meek British Birds article (BB, January 2006, Vol.99) a good discussion of Northern Bullfinch features is available at http://www.abc.se/home/m4046/angarn/domherre/bullfinch.htm

White on primaries can also be good for Northern Bullfinch and ours seems to show this ( and see first photo above), click on photo to enlarge:



And here too ? :





Extensive white underparts may also indicate Northern Bullfinch, not sure if this would quailify, also check light pink breast:




Note the faint pale line under the black cap under the eye. Mark's bird also had this feature. The article I linked to above suggests this is a feature in some Northern birds - not sure of the source though. The white on the coverts doesn't look very wide as a result of the acute angle.

One more for luck:




It is also worth checking Martin Garner's fantastic blog that pushes back the frontiers of birding, and also Northern Bullfinch identification. Martin also has a recent article on Birdguides regarding Northern Bullfinch ID but I am no longer a subscriber (£40 a year !!) so I can't check it - maybe you can.

Calls

The bird (thankfully) did call, and this was very different from the soft  "pee-u" that the (much smaller) bird it was accompanying gave. The big male gave a harsher, more "tooting" call in what we muso's would call sotto voce ("in an undertone"). I checked the recordings on the fantastic Sound Approach Book/CD when I got home a few minutes later and the calls our bird gave very closely matched those on track 95 CD2 - you should all have this book to have a listen, and if you don't you should ask Santa for it ! Trawling the internet I found calls  HERE (for "trumpeting Northern Bullfinch") and these match what we heard today, if somewhat a bit more forced (than ours).

So, is this bird a Northern Bullfinch ? Well, like Mark I can only suggest it has some features and a call that seem consistent with pyrrhula, or at least a European Bullfinch eg. not British:

a) Large size, compared directly with smaller bird it was with.
b) Tooting call; very different from bird it was feeding with.
c) Wide wing bar with "sawtooth" edging on greater coverts; White edging on primaries.
d) Extensive white on underparts; extensive white rump.
e) Pink breast seems to match photos of the type.

Seeing the two Bullfinches together today this bird certainly had 'the presence' that pyrrhula is suggested as having and again we were able to hear the calls of both birds in the field, which were different, and thus compare them. I would certainly appreciate feedback, opinions on this bird ! Maybe it is just an 'inbetweeny' one ?

Tommorrow I will try to get better photos and more importantly decent sound recordings and will report back......maybe the results will be a surprise !

Friday, 17 December 2010

Watch Out ! 'Ere Comes The Old 'Bill ! EDITED

Apologies for paucity of posting lately - catching waxwings, catching up with work, catching colds yada yada...

After my revelatory "new" Scottish Crossbill call announcement, which to my dismay has not yet featured on the front of "Time" magazine, "New Scientist" or the Graham Norton Show, I thought it would be helpful if I posted an 'old' Scottish Crossbill call (click to enlarge):



This flight call was recorded at Glen Tanar NNR on 8th August 2004 with my then trusty Monocor Shotgun mic direct to Sony 710-MD. This call is very much per the literature (Summers et al, 2002) in that it matches frequency and structure for Fc3 = Scottish Crossbill. Note that it appears to show the all important trailing element behind the main "up-down" components of the first element. This is the feature that is generally used to categorize scotica. However, it is very different in visual spectogram appearance and in sound to the 'new' type one I posted on here ( a few posts down). The "new" call is higher piched and the second element is usually higher in energy than in the "old" one. It is as if the call has evolved ....or perhaps it is the crossbills that have evolved ? !

My view ? Well I am not for one minute saying that the example of the "old" Scottish Crossbill from Glen Tanar is not a 'Scottish Crossbill'....except that it seems consistent with birds that I have handled and sound recorded that would be classified as Parrot Crossbill, albeit at the lower spectrum of minimum bill depths (11.9 mm upwards). It also doesn't sound like the 'new' call types ( which appear to biometrically match scotica) - if we take away the second element, which possibly appears to be a harmonic trace of the main call, what we effectively have is a Parrot Crossbill call = Fc2, in fact many caught and released Parrots give a call that contains these type of 'traces':




Not all Parrot Fc's are inflected in the main downward component ! The harmonics here are admittedly much fainter than the Glen Tanar example above, but in terms of sound this is negligible (compared with the new Scottish call). In Parrot, most of the energy is in the main downward component of the first element and it is this, and the lower overall frequency, that avoid confusion with the Fc1 variant I call the "parroty" Fc1. Here is a Common Crossbill call, a Fc1 "Parroty" type that also contains the harmonic artefact:




In essence the'trace' element appears and sounds as an artefact not a feature of the call. In the 'new' Scottish call the second element cannot be a 'harmonic trace' because, if you look at it closely, it modulates whereas the intial element (that it would be tracing) doesn't:




This may be as a consequence of the bird using its double syrinx ? You can really see that these calls look nothing like anything else on this page ! I should add, that although I refer to these particular Scottish calls as 'new' I have actually recorded them since 2004, they are new in that they don't seem to have been described proviously and certainly not matched to biometrics. In the 'new' call the second element functions as a feature of the call, ideed it is the most important structure in giving the call its particular timbre and resonance. To me, this new call sounds completely different, and more importantly it matches the bios and ecology of Scottish Crossbill. However, some Common Crossbills here in Scotland may also give di-syllabic calls that closely resemble these 'new' Scotbill types - the clincher here seems to be that the second element is higher in frequency in relation to the first element with Scottish, though this is pers.obs based on in the hand bios. Time will tell. A final word on harmonics if you use fine microphones ( I use Telinga Stereo DAT, Twin Science and Sennheiser ME67) these harmonics are usually more apparent, especially at closer distances.

So, rather appropriately for this time of year "in with the new out with old" ? But remember folks, I am the one that thinks that the (Scottish) Parrot  Crossbills are the REAL (relict) Scottish Crossbills, so I don't know where that leaves us with regards to "old" and "new" 'Scottish Crossbills' that currently occur in NE Scotland ? Perhaps they are emerging "species" or morphotypes (is that a real word) ? 

Next up, a discussion (including audio examples !) of variant Common Crossbill Fc1's as this really needs addressing.

© Lindsay Cargill 2010, 2009, 2004

Saturday, 13 November 2010

Waxy-Tastic !

As most readers will know there has been a big influx of these fantastic winter vistors over the last few weeks with numbers soaring to the thousands and widespread distribution. As members of Grampian Ring Group we are pre-conditioned to target these birds as Aberdeen is the Waxwing capital of the UK and by colour-ringing the birds we get fantastic re-sightings that describe the movements of these berry munchers (without the need to re-trap them). Birders and photographers seem to like the winter challenge of checking birds for rings so this is a mutually beneficial activity.You could also add to this that Waxwings are simply fantastic birds to handle and work with, so you can see that we don't need to be asked !

I am perfectly placed as I live right next to a city cemetery that attracts Waxwings in numbers, and often can see hundreds wheeling about out of my back window, and occasionally in the trees at the bottom of the garden. Last year was a no go for me as there were no birds at the site, but I was hopeful this year given reports in advance from the Northern Isles and Scandanavia.

On Friday 29th October I speculatively set up a fixed net at a preferred feeding tree and caught a single Waxwing within two minutes, the first mainland caught and colour-ringed bird for the winter. This tree was literally 100 yards from my back door !

On Sunday 31st October myself and a couple of other Grampian ringers caught 43 Waxwings at the same tree, and other GRG members caught 15 elsewhere and 43 at Ballater the previous day, so quite a haul and great team effort !

Numbers of birds increased and by Tuesday 2nd November there were over 1000 at Kincorth, south of the river Dee. This was quite some sight especially when they were in the air ! With up to 400 visiting the cemetery efforts continued from Tuesday 2nd through to Saturday 5th with a further 49 Waxwings caught in the south of the city near my house. Undoubtedly, the highlight on Friday 5th was this Swedish ringed juvenile (which we subsequently colour-ringed Left Leg Orange-Lime-Orange):




This is apparently only the third Swedish control for the UK ( Riksmuseum have been contacted with catching details but I am still awaiting information as it appears a recently ringed bird). It was the first bird caught on a slow morning though we went on to catch another 16 and a very reddy-brown female Sparrowhawk ( that chased a Waxwing in to the net before it too got caught - both unharmed). This Swedish ringed bird, like approx 90% of the birds we have caught, was a juvenile in its first winter:



Sadly, on Thursday evening I was informed that this bird had been found dead on 10th November after striking a window about 3 miles North of where it was ringed. Waxwings are apparently notorious for flying in panic into windows and strikes are a common occurence, often resulting in death. We were all looking forward to receiving sightings of this bird as it made its way south over the winter and the fact that it is a Swedish ringed bird would have no doubt created more interest. Oh well, such is life.

We have continued to catch on a limited basis this week and managed another 9 birds over two mornings - much harder going as the flocks have dispersed and the birds change feeding trees. So my total (on my rings) is 102 from the overall current total of 205 birds GRG have caught to date which is a pretty good total. This should result in numerous reports of colour-ringed birds as they move through the country so do keep checking and report sightings to us via our site at:
http://grampianringing.blogspot.com/.

Thanks to Euan, Callum, Walter and Derek (who came all the way up from Fife !) for help catching and processing birds over the last two weeks.

Tuesday, 19 October 2010

Scottish and Parrot Crossbill Catch and Variant Calls, Tuesday 12th October

After all the wet and windy weather in September (frustratingly coinciding with my days off) finally some moderate sucess ! With light winds and an overnight frost, ringing conditions were favourable and at 12.30pm this cracking female was caught at one of my drinking pools in upper Deeside:


This bird, an adult female had nearly finished its primary wing moult up to P9, though interestingly no secondaries had started moulting yet, and was aged as a 4F ( female hatched before current calendar year). I am beginning to think that some Parrot and Scottish Crossbills don't moult all (or possibly in rare occasions any?) of their secondaries depending on when they finish breeding ? The only other possibility is that it could have been a second year bird that has had an extensive post-juvenile moult where it has replaced it's primaries, but not the secondaries. However, the lack of any old (juvenile) greater coverts, adult type alula and and adult primary coverts discounted this possibility.The minimum bill depth was bang on for Parrot type. It was also 'big-headed' in the hand and was over 50g in weight (typical for Parrot Crossbill). However, though this bird gave a classic Parrot flight call on release (Fc2) it's excitement call (which it gave when it landed) sounded more like Scottish Crossbill ! Indeed, on the sonagram the excitement call (or toop) was somewhere between Parrot and Scottish Crossbill.

So, should we all be concerned by this anomaly and earnestly start burning our copies of "Sound Approach" and "Summers et al (2002)" ? Well no, hold off on the matches and lighter fuel, at least until I offer this explanation. To start with, a fact - Crossbills are social finches, and social finches, have been known to 'learn' calls (see Mundinger). Variant calls, or more specifically a call that appears to contain features of two crossbill types, do not necessarily infer that the individual giving it is of that mixed parental lineage eg. a hybrid. I think it is way too simplistic or convenient to say that because a call appears "half Parrot and half Scottish" on a sonagram that this explains the provance of the bird. The 'white-coats' (crossbill speciation sceptics who constantly cite the lack of gentic divergence between the forms ) as well as cynical crossbill call sceptics will love this bird that I caught - it gave two calls, or a mixture of two, so which call gets precedence, Scottish or Parrot ? How can I call it Parrot when it gave a Scottish type call ? Well, as I said the excitement call had features of both Parrot and Scottish - to me it sounded Scottish-ish, especially the short duration harmonics, but the fundamental note (the lowest note) could easily be interpreted as Parrot in shape. The flight call was a stone-waller Parrot - a big resounding "Ch-oop". If we are going to discuss which calls are more useful diagnostically, flight calls or excitement calls, then I would say flight calls, for two reasons, though this hasn't always been my position:

1) In my studies of the new "Scottish" type calls that appears to have emerged since the last big studies in the 1990's, but picked up by me when I started recording in 2004, I have noticed that the coresponding excitement calls (Ec's) are quite variable - some look like normal Scottish EcC (excitement call C) with typically only one harmonic and the main note either being inflected or not, whilst others give a cross between EcA and EcD, both Common and Parrot type calls respectively. Biometrics collected through catching and ringing individuals have proven the intermediate bill depths of this 'new' call type are consistent with Scottish Crossbill. More on this exciting stuff soon !

2) In the USA, flight calls are apparently considered more diagnostic than excitement calls. In a recent exchange of emails with Matt Young at Cornell late last year, Matt re-iterated this situation to me and asked me what "we" used in preference diagnostically on this side of the pond. "Excitement Calls" was my answer, though this answer was mostly 'conditioned' by the European crossbill literature, and in particular the work previously conducted in Scotland. I then thought about the situation with these new Scottish calls where I was struggling to reconcile matching Fcs to Ec's (in known individuals) and viola, the excitement calls are variable, but the flight calls are (relatively) consistent !

The reason that excitement calls appear to be variable may well be down to the context that they are given - these calls are given in various states of aggrevation and threat, from other crossbills, competitors (such as Siskins) or potential predators, as well as at the nest for various reasons. Excitement calls can also sound quite similar between the species - compare EcA (common) with EcD (parrot) and also EcC (scottish) with EcE (common), they are very similar and are easily confusable by ear. I don't think we fully understand the mechanisms of this yet, which may well affect our interpretation. However, an excitement call, or toop, functions universally amongst crossbills to say " I am not chuffed", "watch out" or "get off" and may vary accordingly, but will presumably be understood across 'species'. The flight calls, on the other hand, are given as contact calls within a flock and would presumably need to be recognizabe to other members of that flock to communicate where to feed and when to leave to feed (or drink) and also for lone birds to locate where flock members are feeding or are safe (eg. on release after being trapped !). These too may be contextual, which may explain subtle variation, for example harmonics are produced with increased amplitude eg. when the bird is in an an excited state and these harmonics can effect the appearance of the call on a sonagram, and may even result in a wrong diagnosis. This said, it does seem that flight calls are perhaps more consistent based on retrap crossbills and ones in situ that have been repeat sound recorded.

So, the bird above I can happily call a Parrot rather than Scottish on:

a) Size, bill depth and bill structure. The Scottish types are over a milimetre less in bill depth, which is overall usually more rectangular, and are up to around 10 grams lighter.

b) Flight call. The Scottish type birds, particularly the "new" ones, give a completely different call. This one gave a Parrot call.

The next bird caught was a re-trap male colour-ringed Parrot Crossbill (initially ringed in 2006, but retrapped by me in 2009):



Thankfully, my bios matched (though 0.1mm bigger in bill depth this time - pine resin ? !) and even more thankfully it gave the same flight call it gave in 2006, 2009 and now 2010 !  Although it is frustrating not to get some new rings on a caught bird, these retraps do give extremely important call and moult data can be compared to with previous years, for example I can compare the stage of moult of this bird with exactly a year previously.

The last two birds were caught at 4.15 pm just as was about to take the net down (having already taken down one net due to an increasing breeze). One was an unringed Scottish female and the other a retrap colour-ringed Scottish male (caught by me in October 2009).

I metal ringed and colour-ringed the female first:



This is a 'classic' Scottish bill profile, intermediate in bill depth and rectangular in shape. Doesn't it look more like a common Crossbill than a Parrot ? ! This female, an adult, was more than half way through her post breeding primary moult but with the secondaries all old. Most exciting for me is that the flight call it gave was one of the 'new' types, different from the published ones. So, a very valuable bird.

An example of the "new" Scottish flight call from a trapped and released colour-ringed bird in 2009:



Unlike the flight calls previously described for Scottish Crossbill these flight calls have a trailing component that is as strong, or stronger, than the intial one ( the opposite of previous Scottish). They also sound very different, more like a "ti-reep", the second syllable being more pronounced. I have recorded these in Deeside since 2004 and elsewhere since. A more detailed preview and summary on these new calls will follow on here soon and I hope to publish the results - I now have my own biometrics and as far as I know this is the only complete data set that has calls to match bios for this 'type' as well as breeding and feeding data.


The male had a slightly smaller bill depth than the female, but still Scottish in characteristic:




Don't worry I wasn't catching crossbills in the dark - it was only 16:30 but the sun, though still high, had gone behind the tall mountains and I had to shoot on flash to get any contrast or colour detail ! This bird didn't call on release ( some don't) but in 2009 it gave the 'new' Scottish type flight call.

New articles and preview of publications coming up soon including Parrot Crossbills feeding on Larch, New Scottish Calls (!!) and field identification of Parrot and Scottish Crossbill for birders........keep tuned and tell your friends.


© Lindsay Cargill 2010

Friday, 8 October 2010

Parrot Crossbill Predation


Eurasian Pygmy Owl and Parrot Crossbill (from http://niaolei.org.cn/posts/10555)



I thought that photo might get your attention ! No not from my Deeside site but rather somwhere colder and much further East ! Apologies to the anonymous photographer (as no name was attached to it) but I have linked to the original website.

Crossbills are strange birds; they are very wary when coming down to the ground to drink, get grit or bones (for calcium) yet when they are feeding in trees you can stand only a few feet from them and they are oblivious to your presence (helpful for reading rings !).

Even with my 1000's of hours field time I have never witnessed Crossbill predation per se eg. an actual kill, though I have observed unsucessful attempts by Sparrowhawks on several occasions, and Merlins (twice), both aimed at Parrot Crossbill flocks. Clearly Pygmy Owls have some adaptation for catching Parrot Crossbills ! Predation by avian predators it would seem is a rare occurence.

In Scotland there are several species that can predate Crossbill nests (eggs and nestling predation): Red Squirrel (Greys don't tend to occur in Pine Crossbill habitats), Corvids, Pine Marten, Great Spotted Woodpecker (and Green Woodpecker at one of my sites) and Sparrowhawk ( I have witnessed the latter though the chicks successfully 'exploded' and evaded predation). However, this said, the severity of the weather, particularly wet, snow and wind combined with the availability of cones (and how 'open' the cones are) will have far more impact on productivity than all the predators combined.



Friday, 1 October 2010

"Last Catch", 30th August 2010

This is my last catch of crossbills, from August 30th in upper Deeside. I caught two Common Crossbills (and a Meadow Pipit !), that were lured in to the vicinity of the drinking pool with a taped call - they were trapped in an area of natural/semi-natural Scots Pine. Common Crossbills have been present, feeding on the pines (which are closed) and nearby Larch and Spruce for the last two months:


Female Common Crossbill


Common Crossbills are usually fairly recognizable in the hand being much smaller bodied than Parrots and a bit smaller than Scottish. The key measrement however is bill depth. This one was quite big with a minimum bill depth of 10.6 mm but still well within range for Common Crossbill.

Common Crossbills can sometimes be difficult to age precisely due to an extensive breeding season that can last most of a calendar year (depending on cone/seed availability) and also due to the fact that some suspend their moult (if irrupting and/or breeding in their 2cy) whilst other juvenile 1/2 cy's can have extensive or erratic post juvenile moult - though the former will still often show 3 generations (or ages) of feather and can be aged quite easily. Another factor is that crossbill 'years' don't necessarily conform to our calender years eg. January to December, and as such the age codes ringers use may not conform like they do for other bird species. The dead crossbills that Dougie Preston sent me from the 2009 invasion had examples of arrested or suspended post juvenile moult - these will feature in a later post.

The female had adult type wing feathers that were quite worn, no old (or juvenile) greater coverts so was aged as a Euring Age 4 or a 4F. She had also replaced two primary coverts (indicated below, and much darker than the older feathers):


Moulting Primaries and Primary Coverts


One of the associated primaries P1, slightly darker than the older feathers, was nearly fully grown and the other was just coming in so this bird appeared to be active wing moult. Another useful ageing criteria was provided by Jenni and Winkler's fantastic Moult book which states that Common Crossbills never replace PC1 and PC2 (primary coverts 1 and 2) or even PC3 as part of their post juvenile moult so the age of a Euring 4 ( born before the present calendar year is safe). This female also had a brood patch score of 4 meaning she must have bred some time over the Summer and would explain the commencement of wing moult with the first two inner primaries.

The male's bill depth was 0.1mm bigger - positive assortative mating ? ! This bird was also in wing moult with two new primaries and associated primary coverts. Quite a big billed curvirostra, though overall bill is 'rectangular', culmen is not steeply downcurved and the tip of the lower mandible is at a shallow upward incline:



Male Common Crossbill


Notice how the bill appears big relative to the size of the head (which was small) ? After releasing the two birds one after the other, and recording their flight calls (both Common type Fc's) I noticed a colour ringed crossbill feeding in a Scots Pine tree right by the ringing station. I got the scope out and it took some time to get the positions of all 3 colours and the metal but I eventually confirmed it as Parrot Crossbill that was ringed 15/10/06 at the same site. This bird was on its own and I took the opportunity to collect and measure some of the cones it was foraging on. The first one it dropped was this cone:


Parrot Foraged Cone



The above cone resembles the shredded appearance of a Scots Pine cone that has been worked by a Scottish or Common Crossbill , yet the bird that foraged it was defintely a Parrot on bill depth and also flight call. So what gives ? Well, clearly like all things crossbill there is no definitive, and inconsitency and variation prevails ! I guess it depends on the structure of the individual cone as the bird then dropped a cone that was more typical of a Parrot foraged closed Scots Pine Cone:


Typical Split Parrot Foraged Cone


I have observed Parrot Crossbills only partly prising open certain cones many times so my conclusion is that crossbills cannot be identified with 100% certainty by examining the condition of the cones that they depredate, though for most birds this may be a safe assumption and is generally useful. Parrot Crossbills 'split' the cones by making an entrance to the scale with the culmen tip then 'working' that hole, by inserting the mandible then manipulating it through up to 90 degrees which then splits the scales - which is why Parrots are 'bull-necked' and have extremely well developed neck and cheek muscles. They will also sometimes literally 'peel' the scales. It is a bit of a 'domino effect' - once they have got one scale open the others are much easier. They will work a cone like this one for anything up to one and half two minutes at this time of year.

Hopefully when the wet and windy weather finally subsides I can get out and catch some more ! A more thorough review of Parrot feeding will appear in the future as I have scads of pictures of birds feeding, including some colour ringed Parrots feeding on Larch ( which apparently they don't feed on according to some authors !).


© Lindsay Cargill 2010




Friday, 3 September 2010

Culbin Sands, Sunday 22nd August

Some of you may have gathered from my tweet that I was at Culbin Sands near Nairn a couple of Sundays ago. For those that don't know it Culbin is a massive Scots and Corsican Pine plantation on the sand dunes south of Nairn. It is home to Corsican Pines, Crested Tits, Scottish Crossbill and Southern Hawker (the target for the day). Below is just a brief summary of the day.




Spot The Corsican Pines ?

On arriving Common hawkers were patrolling the car park and there was an abundance of Scotch Argus butterflies which was a good start. All the way to the main Dragonfly pool Crested Tits were calling and we got great views - even one bathing at around 10 feet (though too shaded for a photo shot). I have heard recent reports of people missing Cresties at Culbin - my advice is to really familiarise yourself with the calls as you will hear birds long before you see them ( a bit like crossbills actually). With so many about you really would have to have been walking about blindfolded and ear plugs in not to have encountered them this day.


Arriving at the main pool Common Hawker males were patroling but within a minute or so a Southern Hawker male appeared followed by another and a dog fight ensued. S. Hawkers, very Common in England, are very scarce in Scotland and only seem to have a hold on this NE corner of Scotland - the area from Banff through to Beauly- and I understand that they are now dispersing South through the Great Glen and are at Fort William. Perhaps like other species of odonata they have been unintentionally ( or intentionally) introduced ?




Male Southern Hawker


We found a cracking Southern Hawker exuvia about 3m out from the bank on a stem. I decided it was worth getting my feet wet so waded out to claim it. It turned out to be a perfect female SH exuvia. More Cresties were calling and moving around the dragonfly pool, but suddenly a Crossbill flew over and Remembird recorded this:



Pants Common Crossbill Sonagram


Now, to my ears this sounded almost cross between a Fc4 (glip) type call and a Fc1 (parakeet), but this is not clear on the sonagram, where the call looks more Fc1 ish. However, though it looks like a Fc1 "parakeet" type ( or 1B) it is possibly slightly too low in frequency for most Fc1 calls and is similar in frequency to Parrot ! To be honest it is like many of the vague calls I get sent by other people and in those cases I often shrug my shoulders, so I am going to practise what I preach with this call I made and call it as "can't be sure" ! What I will say is that aurally ( in the field) it was not Parrot ( which I have much experience) and it sounded 'clippy' so possibly a Fc1 afterall, but just a low pitched one. I think if it was a Fc4 the last ypward component would have shown up.

On the way back to the car, we came across the massive catepillar for a Goat Moth scrabling about on the path:


Goat Moth Catepillar.....Yummy !


Apparently these are quite unusal and scarce so a lucky find. The other Dragonfly pool had 4 Spot Chasers Emeralds and Common Blues but no Common Darters which were present there last year.

If you are up in the Inverness area Culbin is very worth a visit and could easily produce Goshawk as well as the goodies we had. Definitely more Crested Tits than Abernethy from my experience.



Wednesday, 28 July 2010

Getting All Excited About Scottish Crossbill !

I am in process of re-evaluating some of my early recordings for a couple of upcoming papers (finally), one of which is now drafted and just needs the supporting sonagrams and pictures compiled and added in. Raking through the material I came across this sonagram, probably one of my best ever of a Scottish Crossbill, recorded near its nest at Glen Tanar on 11th April 2005 ( yes I really have been doing this stuff since then ! EDIT: actually, since 2004):


Scottish Crossbill Excitement Call


A fantastically clear sonagram of a typical Excitement Call C (EcC) diagnostic of Scottish Crossbill per Summers et al, 2002. The really amazing thing is this was recorded with my Czech Monocor short gun microphone (which was as noisy as hell) and my first Mini Disc recorder a Sony MZ-710 ! Not a Telinga or Fostex in sight ! Just shows you what you can do with a bit of fieldcraft (and field time) and the right conditions ( there was no wind and the bird was alarming about 12 feet away from the mic). In those pre HiMD days I had to re-record ALL the tracks  from the line out into Audio Lab via the computer and then process the sonagrams using a program called GRAM32.

I should add that this call type is now quite rare, having only recorded it in this form a few 'handful and footfall' times. Some interesting material regarding the call structures of Scottish Crossbills is imminent.....all is not what it seems, keep tuned.

Saturday, 24 July 2010

Catching Pine Crossbills, Upper Deeside, 21st June 2010

Crossbills are notoriously difficult to catch in order to ring as you cannot bait sites like you can for other finches - they are specialised to feed primarily on various pine cones and there are usually millions of them about so no joy there ! Usually crossbills are caught when they come in or out of drinking pools. I believe Dutch ringers use 'artificially' created drinking sites and also use caged decoy birds to lure crossbills in which sounds very efficient ( and interesting). Here in the Scotland we only tend to use sites that the crossbills themselves visit naturally on their own accord and we don't use decoys ( though an endorsement to allow this can be applied for). Many man hours can be spent finding and reconnoitring these sites which is why I, and others, are quite guarded about where we are operating and catching birds. Last year one of my pools was compromised twice by photographers (the worst kind of disturbance) so don't take offence if I don't disclose sites, it is nothing personal !

Crossbill's drink obviously to sustain themselves, however, there is also a more 'cultural' purpose to the process. The birds will often sit in a perching tree near to or directly above the pool and the dominant male will sit right on the crown of the tree, sometimes singing or preening. There is a 'pecking' order to how the bird are organised within the tree, with more dominant birds asserting their authority, and often these birds will drink first. One often finds that these birds may actually drink twice - I have observed this several times thanks to colour ringing individuals. However, sometimes extra keen juveniles bail in first and these are often caught more easily. I refer to such pools as 'cultural' pools that is they are long term historical drinking sites where social behaviour and interaction can be performed. This is opposed to sites where they drink 'ad hoc' or opportunistically eg. near to where they are feeding and are thirsty at a particular moment, a puddle below a tree for example. All of this makes them exceedingly difficult to catch in any sort of numbers.

Monday 21st June had near perfect conditions: warm. overcast, and very importantly, little wind. Whilst setting up at dawn several birds came in to one of the pools I was hoping to catch. I backed off and let them down to drink - they could be trapped later when they came back ! I set up two nets and settled down very nearby so that the nets could be monitored constantly.Only an hour had passed and I caught some birds, a family of Parrot Crossbills and a Siskin (other birds drink at crossbill pools). The Siskin was processed first and released quickly.

The male Parrot Crossbill was an adult and was in post-breeding moult ( inc.wing moult):


Parrot Crossbill


Again, the bill structure to me is clearly Parrot, but for many birders this would be classified as Scottish. The minimum bill depth was in excess of 13mm so not Scottish !

The female hadn't started moulting her primaries but some tail feathers were being moulted. She also had a brood patch score (BP) of 4 (meanind she had finished brooding/breeding). The bill structure was Parrot:


Parrot Crossbill


The juvenile had a rather 'clean' look to its bill structure, almost Scottish in appearance but still too deep biometrically to be anything but Parrot Crossbill:



Parrot Crossbill juvenile


These birds were colour-ringed and processed quickly and released into the same tree whilst sound recordings were obtained of their flight calls. The colour ring sequence is unique to each bird and allows the birds to be 'recaptured' (by observation) without actually physically catching it again. Much useful information can be gathered from these observations of colour ringed birds and so far I have very important data on call association, feeding ecology, breeding behaviour as well as site fidelity and movements. The rings have no impact on the activities of the crossbill and some that were ringed in 2006 are still being observed at the same location.

I only had a chance to have a quick drink myself and another bird was caught. This bird, an adult male Scottish Crossbill, already had a metal ring on its right leg so was a retrap. Consulting my notebook it was ringed by myself and my trainer on 3rd September 2006 at the exact same pool:


Scottish Crossbill


This bird was also in post breeding wing moult with several primaries in the process of being replaced.  The minimum bill depth, believe it or not, is over a milimetre less than the Parrots that were caught, even though the shape is similar. This bird was processed and released very quickly, with the flight call recorded as he flew.

There was a lull of a few hours in the early afternoon. This so often happens, the birds just dossing about, preening, singing. Some interesting by-catch kept me on my toes with several Siskins and my first ever juvenile Stonechat. The latter was very interesting as there are usually several pairs with territories at this site but this year there have been none, so the bird I caught was most likey a roving juv from further up the Glen.

By late afternoon the action started again with two juvenile Parrot Crossbills caught in the other net I had set. These were probably caught as I have described above, that is piling in eagerly before the dominant adults ( who then sussed out the situation !). However, though they don't perhaps look as good, catching juveniles is actually better in many ways because we can age them exactly, that is as a first year or Euring 3J. We can also assume that these birds are on their natal site or certainly not far from it, so any movements can be valuable.

The first juvenile I processed had a stonking bill:

Parrot Crossbill Juvenile

From the profile you can really see that this bird, a typical Parrot Crossbill, is 'bill heavy'. Notice the very pronounced gonyeal bulge in the lower mandible.

The next bird, possibly a sibling, also had a pronounced Parrot type bill bill and was slightly smaller overall:


Parrot Crossbill Juvenile

The bird is being held in the 'reverse' ringers grip in order that the tip of the lower mandible can be photographed in the profile. Crossbills can be either left or right handed, or billed as it were, just like humans. I class the cross as being to the right or left based on the direction of the lower mandible tip, in this case to the left.

All in all a very sucessful day with a total of 5 Parrot Crossbills, one retrap Scottish Crossbill, 5 Siskins, 1 Chaffinch and a Stonechat caught naturally without bait. The retrap Scottish for me was the highlight in several ways. Hopefully the in hand bill profiles will be of help to birders in determining ( or not !) the Crossbill species and the text giving an insight in to the intricacy of crossbill study

Friday, 16 July 2010

....Results just In

Well, that was a disappointing turnout given the apparent 'interest' in crossbills and the amount of crossbill sonagrams that are being posted on blogs etc. I don't think there is going to be a rush of contributions so well done to Dougie Preston and Stephen Menzie for being bold enough to have a go, and not a bad go at that, getting the species correct.

I guess people just don't want to appear "wrong" in public and perhaps this goes to demonstrate that identifying crossbills from sonagrams is just as difficult, possibly more so, than identifying them through a scope or images ? Or maybe my example was too difficult ? Well hey, it is a 'real life' snapshot of crossbill behaviour afterall !

Okay, there were two species, Common and Parrot Crossbill and of which there were 4 Common Crossbill individuals of the same 'type' (1A) and only one Parrot specimen. So a total of 5 Crossbills. Only the Parrot gave both a Fc and an Ec. Admittedly the actual numbers of birds was easier to ascertain from the recording which neither Stephen or Dougie had, though it can be seen on the sonagram.

So, here is my analysis ( all timings given are approx.):

1.0 secs = 2x Fc1 types. I call these "parroty" Fc1's as they are easily confused with Fc2. However, they much higher pitched than Fc2 Parrot and the descending element is much weaker ( thinner on the sonagram). Notice one individual is slightly lower pitched than the other, but still higher than Parrot.

1.3 secs = Bird "two"  of Fc1. Continues through sonogram faintly.

1.4 secs = EcA Variant, bird "three". Fundamental has an initial down turn or upturned 'horn' appearance. The harmonics are slightly different from typical EcA.

1.6 secs = Bird "one" of Fc1.

1.9 secs = EcA variant, bird "four".

2.0 secs = Fc1, bird "one".

2.2 secs = EcA bird "four".

2.6 secs = EcA bird "four".

2.8 secs = EcA bird "three".

3.3 secs = EcD Parrot Crossbill. There is no coinciding Fc here ( sorry Dougie) it is a feature of the excitement call structure (though may be related to a fc?). Notice how the Parrot EcD is lower piched and of a considerably shorter duration than the Common Crossbill EcA ( which they can be confused with aurally).

3.8 secs = EcA bird "three" and "four" together.

3.95 secs = Fc2 Parrot Crossbill - same individual as 3.3 secs. Compare with Fc's at start of sonagram, notice the Parrot calls are lower in frequency ( I call it pitch cos I hear it) and are a much stronger in amplitude. This gives a "choop" rather than "cheep".

4.1 secs = EcA bird "three".

4.2 secs = Fc2 Parrot ( same bird as 3.95 secs).

The appearance of a seemingly extra component on the Parrot Fc's at 3.95 and 4.2 secs can be misleading and may in the past have led to examples of this call being classified as Fc3 Scottish ( all will become clearer soon !). It is a harmonic of the main trace in my opinion. Only large billed birds I have handled have given this call on release.

So well done lads, other than the Scotbill reference, you got the right answer ( though the working out may not agree with my own analysis).

Just shows what information you can get from a sonagram. And there are people that say Crossbill calls are baloney ! Their loss.......

Wednesday, 14 July 2010

S'on-ly A Game !

Many interesting revelations to come in the crossbill world very soon so keep posted but meantime a bit of fun ! If Menzie can put up blurry, dodgy pics of his Spanny birds and ask "how many species" then so can I with Crossbills. To make it easier though rather than photos of crossers, which most people seem to get wrong or concede "they just don't know", I have this sonogram instead:




It was recorded on 16th April 2009 in upper Deeside, native Scots Pine habitat (using ME67 and Sony HiMD). So, how many crossbills and of what crossbill species, and more importantly how many call types ? I bet Menzie gets them all correct, he always does !

Posts are moderated, but I will put the non Chinese spam ones on honest !

Spread the crossbill love.

Monday, 5 July 2010

"Northern Exposure", Crossbills in Northern Isles....Again !

For the past few weeks (since approx. early/mid June) Common Crossbills have been trickling in through Orkney, Shetland and North Ronaldsay. Readers may recall that last year there was a biggish influx of type 4E Common Crossbills to mainland Scotland ( and presumably UK). I picked up  birds in decent numbers in lower Deeside by early July, where they had not been present previously that Winter/Spring.

Okay, guys and gals in Orkney and Shetland, what call types are you getting this year ? It would be very interesting to know. Colleagues in Grampian Ringing Group had a ringing recovery of a Common Crossbill in April near Dufftown. This bird was ringed in September 2009 in lower Deeside so had moved Northwards somewhat in the six months since ringing. Was this a bird returning 'back' to where it had come from ? My instinct is 'no', it was possibly part of a nomadic post breeding flock that was seeking a decent cone crop. But the possibility remains, especially given the accepted view is that birds move south and westwards.

So if this years influx of Commons on the Northern Isles is giving 4E calls does this mean they are last year's birds going home ? Maybe and maybe not. Maybe, for the scant evidence cited above and 'not' because some 4E's may have remained in Fennoscandia where there was a localised food source and are only moving now after breeding ( there are juvs in the recent photos I have seen of birds on Shetland). This is this 'lag' effect I spoke of last year, and this would depend on how far from the East the birds were erupting. However, if the calls of this years irruption is different from 4E then at least it rules out the 2009 population returning or a new one of the same type irrupting. As I recall there were some 1A's and 1B's last year also, though in much smaller numbers than the 4E's.


4E Common Crossbill


The other intruiging possibility is that of small numbers of Crossbills trickling in during the winter months and early spring. I have had Common Crossbills at coastal sites in November and December and two flew over my garden this April ( there is no substancial viable food source near me and I am less than a mile from the coast). These may also have been birds moving Northward back up the coast. However, I would expect the legions of Vismiggers to have picked up such movements if they were happening with any regularity ?

If anyone wants to post comments please do - I have not completely disabled the comments but am unfortunately having to moderate them due to the chinese spamming that seems to be more and more prolific on blogger these days !