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.