JULY 2009'S MYSTERY BIRD ANSWERS

Another great effort by all involved with 24 entries received for this months round, especially as it features everyone's favourite, another gull!

Mystery Bird 13

What the...? Yes, the air turned blue and my name was mud yet again as this odd looking creature appeared on your screens. And it's not even a gull! Six species were decided upon as fitting the identity of this bird; Dunnock, Starling, Treecreeper, Wren, Spotted Flycatcher and Robin. On the face of it, it appears to be a genuine LBJ (little-brown-job). Quite a deep and rich dark brown on the upperparts, a fairly distinct pale supercilium extending to the rear of the ear coverts which are themselves fairly well mottled. The underparts appear quite pale with more than a tinge of brown while the bill looks quite long, very slim and has a paler yellowish/flesh base to the lower mandible. Agreed?  We can eliminate Spotted Flycatcher fairly easily for it lacks any supercilium, is much greyer on the upperparts and has a much shorter, deeper, more robust looking bill. Starling too, which received four votes, goes the same way, it lacks the richness of the upperparts here, such a distinct supercilium and it's bill is altogether different. It might, at this point, be worth mentioning also the birds apparent size. Of course, judging such a thing without comparison is very difficult indeed but that the bird's chosen perch is Hawthorn we might be able to fairly accurately assess that the bird is in fact quite small. Hmmm? Dunnock and Robin go the way of elimination next, both lack such a pale supercilium (juvenile Dunnock would also be well streaked below) and once again their bills are comparatively shorter and deeper. So, Treecreeper and Wren left. Our mystery bird, if we look very closely, does have some barring evident on what may be wing or tail but as it is rather closely barred dark on paler brown does that fit Treecreeper so well? Coupled with the fact that our bird has a straight bill (draw a line along it if you don't believe me!), a solidly brown crown, pale brownish underparts and lacks the paler wing covert tips of a Treecreeper that would be evident even here, we can be sure that this bird is a Wren. It's always nice for such a common bird to throw a spanner in the works, do we really give them the 'binocular time' they deserve? Thirteen entrants managed to correctly identify it so well done to Caroline Clay, Nick Godden, Dean Hutchinson, Simon Warford, Dave Broome, Rob and Sonia Adderley, Mike Chorley, Henry Cook, Mark Rigby, Dennis Latham, John Rayner, John Tymon, John Frankland, Mike Passant, Paul Brown and Phil Greenwood. Many of those correctly identifying the bird also went on to correctly identify that it was a quite bedraggled and wet specimen!

Bedraggled Wren, Pennington Flash, June 2009 (John Tymon)

Mystery Bird 14

Right, are we all liking gulls yet? That'll be a no then will it? Atleast everyone had a go and gave the bird some thought, a process that will hopefully go to extending your knowledge of them. That or your loathing for them! Either way only half of the 24 entrants got this one right and in an attempt not to bore the pants off or bamboozle with gull terminology those bothering to read this, we'll close this birds identification succinctly. Or should I say, try to!

For our 24 entrants it boiled down to Common Gull, Ring-billed Gull, Lesser Black-backed Gull, Herring Gull or Yellow-legged Gull. First port of call should be it's ageing but working with the gulls we are presented with that brings but more potential complications and given it's near-adult appearance is less necessary. Herring Gull (one entry) is the easiest of which to eliminate, as it's upperparts in the argenteus race offered are more obviously paler than our mystery bird and the extent of black on the outer primaries is too extensive for argenteus also. Lesser Black-backed Gull (with three entries) is also incorrect but it's elimination is potentially less straight forward. A rather subjective appraisal of it's upperpart colouration compared to the black of the wing-tips, using the right wing especially as it is not in shadow, finds the tone of grey to be too pale for a graellsii Lesser Black-back' which is more plainly slate-grey. Of course judging grey tones in the field is difficult enough, let alone from photographs but I have ensured that the tone on the mystery bird is spot on for it's species, but like I say it is admittedly subjective! Common and Ring-billed Gull in the plumage of our mystery bird would have to a 2nd-winter/summer with such a combination of black in the greater primary coverts and a completely white tail. Ring-billed Gull ( one vote) is however quite a pale tone of grey on the upperparts, similar in fact to Black-headed Gull, that makes our mystery bird too dark for that species and with it, it's gone. That leaves Common Gull and Yellow-legged Gull. Two species with similar mantle tones but different jizz, though of course in this instance their general impression and shape is of little use and we need to rely on something else to separate them. With that we must take a look at the primaries and more specifically the extent of the white mirrors in the outer two. As second winter/summer Common Gulls have more black on the primaries than adults it brings their primary pattern to within the range of Yellow-legged Gull but Common Gulls in this plumage would show considerably larger white mirrors to the outer primaries and despite variation (especially with the size of the mirror on P9) it should never approach our mystery bird. I could go on about an overall feel for the correct species, of it's length of wing (compared to the tail especially) and fullness of primaries which also assists our identification for I believe it has but that relies on a very sound appreciation of both species. So, the correct answer is Yellow-legged Gull but there is, as there is for every mystery bird answer received, no disgrace in getting it wrong.

Those 12 entrants getting this one right were Geoff Hargreaves, Rob and Sonia Adderley, Tim Wilcox, Mike Chorley, Mike Cooper, Tony Coatsworth, Mark Rigby, Denis Latham, Dave Broome, John Tymon, Helen (lovin' gulls now) Garwood, Mike Passant and Paul Brown.

Fourth winter Yellow-Legged Gull, Pennington Flash, September 2009 (John Tymon)

This challenging round produced only eight entrants managing both species correct so it was a good effort indeed by Rob and Sonia Adderley, Mike Chorley, Mark Rigby, Dennis Latham, John Tymon, Dave Broome, Mike Passant and Paul Brown. Of course Mr.Tymon succeeds by default as he took both images in the first place but having come to my rescue when I had exhausted my selection of mystery bird photos he deserves something, so well done John ☺. Let's see if you can repeat the performance next month!

There was no change at the top though and there was no fooling Paul Brown, still not only the competitions leader at this point but also most northerly entrant. With only five months left to run it will be a difficult job to catch him but as we enter the autumn run for Orkney's jewel isle one might still expect the competition to slip is mind when his mist nets are heaving with migrants.