Tuesday 12 February 2013

Stringy Rook and another hybrid Herring x LBB Gull?


I managed to squeeze in a couple of hours of gulling today. As the tide was in I checked the loafing area beside the pipe-pile at Seafield but found it almost deserted. After twenty minutes the best I could do was a handful of BhGs, Herring Gulls and a single Lesser Black-backed Gull. Scanning the corvids revealed two hybrid Hooded x Carrion Crows on a roof and a distant static Rook on a pole atop a portacabin. Switching to my scope the 'Rook' morphed into a falconer's Harris's Hawk (!) tethered to the spot. Ha! I wonder whether that is the first time that particular misidentification has been made? The bare skin around the bill and dark plumage had been massaged by my brain into the most-likely candidate... So, my second exotic raptor of the year, and the reason why the gulls were largely absent. Deterred, I headed around to the sewage works where it turned out there was lots of gull activity.


I was hoping for a white-winger of some sort but the best I could do was this possible hybrid Herring x LBB Gull. Possible argentatus Herring Gull given the wingtip pattern and pinkish leg colour (with only a hint of yellow). Characteristics favouring hybrid are the slight build - much more like a LBBG than a Herring Gull and the mantle shade that seems to me to be too dark to be an argentatus Herring Gull. Any ideas?...

The same bird was easily picked up when it moved to the sea. Unfortunately the light was poor...

2 comments:

welchs said...

Agree that looks the most likely option - it has nothing to suggest argentatus and if it were a LBB you'd be struggling to explain combination of pink legs and rather pale mantle. Is it just a coincidence more of these are coming to light, or rather that someone (you) is making the effort to look and document them?

Morg said...

Glad you also think the hybrid option is probably the most likely. Maybe third time lucky and I'll get my YLG, eh?

I don't think that we can draw any conclusions about the number of these birds to be honest. They are certainly not common for sure. If they are on the increase then I would suggest that the change in wintering status of LBBG would most likely have something to do with it. This year I have had winter LBBGs at wrecked Craig's (Lucy?), colinton road (dec, jan and feb sightings), liberton (jan), little France (jan twice) and sea field (dec and feb). While the former four locations could be the same bird it is likely that at least three if not four individuals are involved. If any of these birds felt like courting at the moment then a HG would be the only option...

Now that bird track is an iPhone app I'm planning to start logging these things you'll be glad to hear!

Geoff