Friday 12 March 2010

And now for the 'science' bit

Well maybe the word 'science' is a bit strong?

Put together a complete technophobe and a complicated subject such as Crossbill vocalisations, and it's a miracle that I got any recordings at all, but get recordings I did, and a few of them were good enough to id too...

Crossbills were only looked for in native Scots Pine forests, due to the fact that the cones should still be closed at this time of year, and only the larger billed birds (Parrot & Scottish) should be able to access the seeds. This fact seems to have escaped the attention of the birds themselves, as I recorded 'Common' Crossbills in all the woods checked!

The first sonogram shows what is commonly known as a Fc4 (or 4E's depending on the classification you follow). These birds were quite scarce in Britain until last Summer, when there was a large scale invasion. These vocal types were the most abundant birds I recorded in Shetland last year, and thus before then would have been a good find, but now they seem to be everywhere.

Also got a bit of a dodgy sonogram of what looks like an Fc1 (1A) If you squint carefully you can just about to see it...I recorded only two of these in the 2009 Shetland invasion! (Sorry about the poor quality)

But...These ones are slightly more interesting (to me at least!), They were described to me by Magnus Robb (of 'Sound Approach' fame) as a probable variant of the above Fc4. Typical eh. Just when you think you are getting a handle on things, someone shows you that you really don't know what the hell your talking about.

Well, just looks like I'm going to have go back to Speyside to try getting more recordings...Oh dam! (If I have too).

I hope this just goes to show all those people who have either Scottish or Parrot on there lists, based purely on habitat or time of year they seen the birds. May well be wrong! Without recordings, In my opinion, only large billed Parrots and small billed Commons can be confidently identified in the field. As the overlap in bill size between large Common and small Scottish, and large Scottish and small Parrot make sure things ain't all that easy! I'm surprised there ain't more people out there with recorders...

Any comments on the above sonograms are most welcome.


  1. Hi Dougie,

    Your songagrams all looked Common to me as well - even the Fc1 type you sent me has a hint of an uptail so maybe all Fc4 types ? It is difficult without hearing the samples.

    Yes, not safe to assume Commons will not be present in Pinewoods in early March - some will have been intermittently on pine all winter, at least locally where other food is not present. The cones have been open for a few weeks here so Scots Pine is now available to all species.

    As someone who studies "Pine Crossbills" I am not sure their calls are necessarily 'cast in stone' either, and I use several criteria in id'ing them now.........

  2. Thanks for that. The info on "Scots Pine cones being closed at this time of year" was gained from one of the many papers I'd read on the xbills. Looks like they may have to be taken with a pinch of salt? I'm hoping to try recording in Speyside again in a few months time, so if you'd fancy a day teaching the finer points of call id?

  3. The SP cones generally open in Feb, though last year some were open in late December ! I think it is generally accepted that for surveying purposes Scottish ( and Parrot) will be on territory in Feb/Mar, coinciding with most cones opening, seeds being more available and breeding intiated.

    I had all 3 species on Monday on native pine: mostly Scottish type birds and the Commons were 4E's. The few Parrots I observed were much more 'orange' than the redder Scottish and Commons. A few of the Scotties peeled off to feed females on nests some bit away.

    May/June is good as there should be a lot of noisy juvvy begging calls ! By June I should be catching again and may be able to do this in Speyside with a bit of negociation. Seeing crossbills in the hand will change your perspective on their identification !

  4. Cheers for that. Sounds like you had a good time then!

    If you do manage to get out ringing, then I'd definately be up for helping out/observing, plus any excuse to get a few more recordings of course...

    On the subject of recordings. Looks like last years recordings I made in Shetland have added a new 'vocal type' of Crossbill to the Shetland 'list' (they use the Sound Approach system of classifying calls up here). Until last Summer, we had only had 'Wandering' and 'Glip' recorded up here, but it looks like I managed to record 2 'Parakeet' on Unst, along with copious amounts of 'Glip'! So looks like it was a good move to take up recording then...

  5. The calls from Unst you sent me in July contained Fc4 and Fc1B according to my analysis back then - see my emails to you 8/7/09 for full details.

    I use 1B to denote the "parakeet" variety - I prefer the RSPB system, though 1B is not part of it. Your 1B call however was not typical for this form, it is a call type often given by young birds eg. first years (based on ringed releases).

    I also had some standard Fc1's eg. "British" from Orkney last autumn, the same type that invaded in 2008, so that makes at least 3 'types' that invaded in 2009. I am not surprised by this.