Saturday, 27 January 2018

Caspian Gull !!!

'Caspian Gull' was my immediate thought when I set eyes upon a very bright headed 1st Winter gull on the Axe estuary on 17th January (after missing the Glauc by minutes). Up until this point I had never seen one but have read blog posts by Steve and Gavin enough times to know that a very bright headed 1st Winter gull is interesting. As such I took a few snaps of it. I nearly sent 'possible' news out but talked myself out of it as it was getting late and frankly when it comes to 'good' gulls I'm pretty inexperienced.

There were a load of other reasons I doubted myself. Another birder was present and scanning the same birds but thought nothing of this bird when I mentioned it. I'd never seen one so had nothing in the 1st hand memory bank to compare it to. It didn't look like a 'classic' 1st Winter Casp from either the Collins Bird Guide or the local blogs, although there's obviously going to be variation from one bird to the next. Thoughts of hybrid ran through my mind and I'd missed the target bird (Glauc) so I headed home, slightly bemused. Then a disgusting illness hit and the pics didn't make it off my camera.

Roll on a week and still not happy with what the bird was, I put the pics on the PC and had a look. Still favouring Casp but not 100% confident I sent some pics to Steve and he said Casp straight away. He mentioned a few things such as the dusky flanks and extent of black barring on the tail not being typical (although within variation limits) and these features are amongst what put off my confidence with it. Also the open wing illustration in Collins looks pretty different but again that could be variation. That's where experience with seeing multiple examples of the same species counts I guess; I didn't know what would and what wouldn't be within variation for a 1st Winter Casp, even if the initial impression of the ID was indeed correct.

I also sent some pics for Gav to examine as Steve thought my bird on the 17th may be the same one that Gav had on 22nd; looking at the pics side by side this does seem to be the case. Gav confirmed this over a Twitter chat and we should be seeing a photo comparison on his blog soon... He also sent me a reading list. An initial glance over the Gibbins et al documents had me feeling slightly out of my depth but having spent a few hours with it today I'm now a bit more comfortable. I put my pics through the 'system' of tables from the papers and they place the bird as a Casp; it's reassuring to have some sort of numerical system to help with ID as it helps remove opinion and self-doubt from the scenario.

Thanks go to Steve and Gav for the confirmations and resources.

So I dipped a Glauc but found a Casp. That'll do. There are a few things for me to learn here, the main one being to put more trust in my own initial impressions; they didn't fail me in similar scenarios with half a dozen or so juv Yellow-legged Gulls in 2017 and they didn't fail here either. Still a 'beginner' with gulls, but learning. Another thing to take from this is to whenever possible, take pics of anything which you think looks interesting!

I spent another hour or two looking at gulls on the estuary late afternoon today. What is happening to me..?


  1. Good photos are so helpful when it comes to birds like Caspian Gull, and these are excellent Tim. Kudos to you for noticing this bird in the first place though, and following through with it subsequently.

    Those two BB papers by Chris Gibbins et al are definitely not elementary-level material, so well done for getting stuck in and coming to your own conclusions. I'll bet you learned a lot from that exercise! Casps will be very much on your radar now, and I'm sure this bird won't be the only one you'll find on the Axe!

    It was Steve who suggested my bird of Jan 22 could be the same as yours, and I'm convinced he's correct. Now that you've posted this I'll get working on a blog post to demonstrate exactly why.

    1. Many thanks Gavin. Yes those papers are certainly very useful; hopefully you're right and this won't be my last!
      I look forward to your post comparing the pics from 17th and 22nd...