FEBRUARY 2010'S MYSTERY BIRD ANSWERS

An impressive 35 entrants continued their participation in the competition and their distribution showed the true draw of this, potentially the last mystery bird contest of it's kind, with entries across Britain from Orkney to Avon and as far a field as Switzerland and New Zealand. Many thanks to you all and now it's over to those absolute stinkers (the words of one entrant not mine!) of mystery birds. What the hell were they?

Mystery Bird 3

Let's narrow this one down. It's a warbler of some description! Okay, in fact warblers from three 'families' were offered by those 35 entrants, Acrocephalus, Hippolais and Phylloscopus, which might seem surprising as they should all be rather different to each other structurally atleast but as is often the case, it's never quite as easy as the field guides might infer. So what does this mystery bird afford us to go on? Time to get down and dirty...

Cutting to the chase as they say, four species were submitted as answers to our mystery warbler. In the Acrocephalus camp there was Marsh Warbler (6% of the votes), the Phylloscopus camp was represented by Willow Warbler (69% of the votes) and the Hippolais camp featured Icterine Warbler (23% of the votes) and Melodious Warbler (3% of the votes). Firstly, we can rule out Melodious Warbler straight away as our mystery warbler has primaries clearly too long for Melodious as they are approximately as long as the tertials. So, rather than rule out any of the other suggested species lets look at it the other way, let's look at what we can see that makes it what it is. Looking closely at the bird there are a few instantly obvious features about it. The fleshy coloured legs are immediately arresting, the long primaries have already been mentioned but the striking pale wing panel formed by the edges of the secondaries have not. The actual plumage colouration is in fact difficult to assess, the bird appears rather greyish/green above and yellow below but let's look at an external feature for a second. The photograph is patently taken with strong sunlight coming from the left and the foliage the bird is amongst is a very strong green. Could this affect our assessment of the bird's colouration? The truth is yes, and it happens regularly enough out there in the field too when the effects of reflection off foliage in strong sunlight is not taken into account by observers, often leading to birds appearing a brighter, more yellow or green than they actually are. So if we should not place too much emphasis on the bird's colouration from the image we must look elsewhere. Time to take a step back and look at the whole bird then, to trust our perception of the bird's overall general impression of size and shape. Jizz if you will! It strikes me as a rather robust looking bird, it is somewhat long looking, has sturdy legs and a considerably broad based, strong bill. To my eyes it structurally smacks not of a Phylloscopus warbler and despite Willow Warbler having similarly long primaries with spacing in between tips increasing towards the outer primary they are more subtle, have a 'shorter' overall look and less robust legs and particularly bill. For Willow Warbler one too cannot place that pale wing panel. As the wing in question is in shadow we can be sure that it's effect is not due to any consequence of lighting and that it is indeed produced by striking pale edges to the secondaries, something no Willow Warbler or for that matter Marsh Warbler would display (I could also go into primary emarginations as an exclusion for the latter species but fear you'd all fall asleep!). We have in the process above, succinctly eliminated our two remaining incorrect answers of Willow Warbler (with a massive and quite understandable portion of the overall votes) and Marsh Warbler (whose two votes both came from ringers?) thus leaving us with our correct answer. The mystery bird is an Icterine Warbler. Take a look again now you know the answer, the overall rather heavy feel, the broad based bill and sturdy legs, really long primaries and conspicuous pale secondary panel all point to that species. "Legs" I hear you all shout, "it's got pale legs". Has it? The leaves on the tree are a quite bright mid-green and their true colour can be seen on those above the birds head but those by it's legs look particularly yellow due to the strong sunlight shining through them. Could this effect the colour of our Icterine Warbler's legs? Shine a torch through the palm of your hand at night and the light shines through turning it reddish/orange in the process. Shine a bright like through the thin legs of a warbler and the same is true to a greater effect. Look again at the bird's 'feet', principally around the 'ankle' and you will see that the thicker, more boned section belies it's true colour, especially on the far (right) leg.

I openly admit that this was a difficult bird, it was (not intentionally) somewhat misleading and required assessing from various perspectives but it was manageable as eight entrants proved. There were a great many excellent explanations from all entrants on why they felt the mystery bird was what they thought and this gave me a wonderful insight into your thought processes and perhaps where some went wrong. In the end though, those who managed the correct answer all gave much consideration to the overall 'feel' of the bird. Most had good experience of Hippolais warblers but atleast two had none at all, proving it helps but isn't always necessary. Those eight wonders of the Manchester Mystery Bird World were Mike Cooper, James Latham, Neil Calbrade, John Tymon, Paul Brown, Gary Crowder, Tim Wilcox and John Rayner.

Icterine Warbler, Corfu, Greece, August 2009 (Neville Wright)

Mystery Bird 4

Yep, it was indeed a 'bit abstract' this one and that was evidenced by eight species being considered as answers to the bird's identity. Eighteen entrants came to the same correct conclusion however but the overall species suggested involved Teal, Pintail, Barnacle Goose, Gadwall, Garganey, Eider, Ruff and Greater Scaup. The very finely vermiculated black and white pattern excluded all but Teal, Garganey, Pintail, and Scaup but it's consistent broad black and very narrow white pattern further excluded Greater Scaup and Garganey. Pintail (adult drake) too has vermiculations not quite as predominately black as this and the same could be true of Teal but the longer feathers at the top of the image are surely scapulars and if so the lack of any horizontal black or white areas below them excludes drake Teal (and Green-winged Teal which would of course lack the white too!). The scapulars are also clearly hued warm brown , once again upholding our 'non-Teal' theory and the overall appearance doesn't fit true for drake Pintail either which finally gets laid to rest as not applicable! That leaves us with one species, Gadwall and as you can see below, those eighteen who went for that species were right. Well done.

Gadwall, Pennington Flash, January 2010 (Dennis Atherton)

A genuinely difficult round caused many to slip up but we can't get them all right now can we. Well, some can and six indeed did so 'doff your cap' to James Latham, Neil Calbrade, John Tymon, Paul Brown, Gary Crowder and John Rayner.

This round saw a more compact overall leading group appear as only five entrants have managed four correct answers so far but the chasing pack is large, only a point behind and hot on their heels. So until the next round, the leaders at the moment are James Latham, Paul Brown, Neil Calbrade, John Rayner and Gary Crowder. Until next time...

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