Monday, 30 December 2013

More Northern Delights and a Troublesome Larid

I managed to squeeze in one more morning's birding north of Aberdeen on Saturday. The plan was to hit the Ythan area (just 15 minutes away) shortly after dawn. At the A90/ A975 near Newburgh I stopped to watch a murmuration of perhaps 10,000 starlings - always a beautiful sight.

I was going to head to Meikle Loch first but something drew me down a minor road in the opposite direction - the coast. I arrived at a village called Collieston and was delighted to find several thousand gulls strung out along the coast, doing battle with the elements as a savage sea threw towering waves at a series of small rocky inlets.

I haven't done gulls for a while, in fact most of my 'gull-watching' was from last winter at Milton Tip. I quickly picked up a 3rd winter Iceland gull. There were red-throated divers offshore, a passing common scoter and a long-tailed duck. I settled down for the morning and eventually found another Iceland gull - a 1st winter feeding in the surf.

2nd winter herring gull, presumably argentatus - sometimes get mistaken for smithsonianus when this dark

Adult Argentatus herring gull - large, dark bird from Scandanavia with reduced black on wing-tip

1st winter Iceland gull

3rd winter Iceland gull


Then to top it all (or so I thought) I saw this.

It appeared to be a 2nd winter Kumlien's and I rattled off hundreds of pics despite the poor light. (Perhaps surprisingly I've not seen Kumlien's gull in the UK or Ireland - just a couple of adult-types in Canada, but I did see a probable Thayer's-Kumlien's intergrade in Oxfordshire a few years back.) Just before I had to leave I spotted it roosting on a nearby pier and snuck up on it for some digiscoped action. Had I have looked at it properly I might have picked up on some anomolous features but as it was I was behind schedule and raced back to my in-laws from where I headed south with the family to Cheshire where we had an overnight stop at a hotel on our way further south. I stuck a pic of the gull on Facebook and had some interesting feedback (from Ollie Metcalf, Rich Bonser, Julian Hough and Ash Howe - thanks guys) which caused me to go through my photos on the journey, looking at the bird more carefully. The bird was not an obvious Kumlien's - it was too dark and large-billed and the tertial/ covert pattern, pale eye and primary pattern were all questionable. The dreaded 'H' word raised its ugly head. I'd been complacent and forgotten to consider hybrids, a schoolboy error! It now appears to have been a glauc x herring, a common cross in Greenland and Iceland (often given a name in its own right, 'Nelson's' technically for a Smithy cross in N America or 'Viking' gull). I've seen one or two myself and found no problem realising what they were as I was watching them, but this one was smaller, herring gull-sized with much paler primaries than those I'd previously seen and it had got me. I think it's important to admit when you've made a mistake, learn from it and move on. Though I quickly realised it wasn't a Kumlien's I was slow to accept it as a herringxglauc as it did not fit my search image of this, so well done to Richard and Julian for pursuading me. A wise man once said he who professes to truly understand the complexities of Larid identification is merely a novice...OK, actually that's bollocks, I've just made it up myself, but I'm sure my meaning is clear - gulls are a headache and if you're not a Larophile yourself you're better off phoning a friend (who is)! Or checking your photos before putting a name to something. Photography is in fact a mixed blessing - it is absolutely invaluable for help with complex i/d's but tends to take over from watching the bird - now I tend to base most i/d's on a quick look before I spend the rest of the time taking pictures, and often I forget to watch and enjoy the bird! I think with tricky gulls a sound i/d should not be made prematurely but only after you've carefully examined the evidence and considered all possibilities.

UPDATE 3/1/14  Having spoken to various others and examined lots of shots on the web it appears the identity of this gull is likely to remain unresolved as a Larus spp, probably a hybrid of some description. Some favour a Viking-type (though it's rather small and the primaries are somewhat paler and plainer than those of most herring x glauc crosses I've looked at), others a dark Iceland gull and at least one other local observer has seconded a suspicion I'm currently harbouring - could it be an Iceland x herring gull? Just a thought - I guess we'll never know.

could it be a herring x Iceland gull hybrid?

2nd winter Kumlien's is highly variable in appearance (and little more than a hybrid swarm itself in the eyes of some) but compared to this bird should look 'cutesier' with a dark eye and smaller bill with clearer-cut tip. The brown wash on the primaries would be more obviously darker on the outer web and (usually) faded or absent on the inner primaries. It would usually look paler below with a different patern on the tertials/ coverts. Some pale Kumlien's are indistinguishable from glaucoides with only the faintest amount of brown along the primary shaft/ outer web

looking uncharacteristically dark in this pic alongside an Iceland, so perhaps not a good representative shot

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