Thursday 17 October 2013

A fun evening in... sorry it's about Gulls!

This gull has been giving me a little bit of a headache this evening. Took the pictures last week and haven’t really looked at them since. Thought the bird was initially a Yellow-legged Gull, the darker mantle, slight yellow tinge to the legs but something was telling me it wasn’t quite right or at least there were a few small issues with some of the birds features. If your interested in Gulls read on but if your not then give up now and go watch TV or something.



Firstly, just look at the age of this bird. When I saw it in flight I put it down as a 3rd winter bird due to the dark primary coverts and the head streaking and dark patch on the bill. However, a few things didn’t add up. I realised it should have more black in the wing if it was a 3rd winter plus it’s got a pure white tail. So am I’m dealing with a 4th winter bird?? If this is the case I’m now in uncharted territory, that’s not an age I’ve looked at the before. Things that strike me if this is a 4th winter is that it should probably have a whiter head. Even a 3rd winter has a fairly white head in my experience. Also, the legs are very washed out though this is a variable feature anyway but on average should be a lot yellower at this age.  Yellow-legged Gulls are often more advanced in their plumage and moult when compared to Herring Gulls. This poses the question ‘is this just an advanced 3rd winter bird?

Assuming that then, take a look at this wing shot.



But compare is to this 3rd winter bird taken a few years ago around this time of year. Quite different!



 Had no doubt what so ever when I saw this bird first! Worth comparing that last shot with the first photo of the bird in question.

This evening is the first time I’ve gone through these photo’s so I’m typing this as I’m going through the details. This photo left me rather confused. There should be a small mirror (a white blob) on P10. Can’t see one there plus P5 is unmarked. Surely not a good thing for a Yellow-legged Gull. Then of course I realised the possibility that P10 could be hidden and this photo reveals all!


Top bird by the way and for comparison, the bird on the rail is a 3rd winter Herring Gull.

Small mirror on P10 and now P5 is strongly marked. Both things fit in with Yellow-legged Gull I think. Interestingly this feather still seems to be growing which has now put a little doubt in mind as to the species. Having already said that Yellow-legged Gull moults earlier than Herring Gull (and other species obviously) this strikes me a being late. I use the moult thing often with 1st years but perhaps with other ages it's not such a good thing to dwell on? There are a few adult and near adult Herring Gulls about just finishing off their moult at the moment but I think most have now finished. Not sure how relevant all that is but interesting none the less.

One of the biggest worries with this bird was its shape, structure and size. It wasn’t a particularly large bird, wasn’t  long legged, its bill didn’t seem particularly impressive and it didn’t really look long wings. The last feature I’ve obviously explained as P10 is still growing. This next shot shows it next to an adult Herring Gull. Structure can be slightly different between sexes, so going by my experience again, this is probably a female as they are smaller than males. 



 I suppose actually its fairly chunky, large headed and the bill I guess is fairly thick set. I was initially looking at the first picture rather than one comparing it to a Herring Gull. Structure can be slightly different between sexes, so going by my experience again, this is probably a female as they are smaller than males. 

So, I better wrap this up as if you've made it this far through the post you’ll sure be getting really bored by now!


It’s a bloody Yellow-legged Gull for gods sake. Experienced gull watchers would be probably just go with that straight away but I for some reason enjoy going through every little detail, doubting myself, then eventually go back to my initial though. Anyway, that was an little insight to how I sometimes spend an evening! I think there’s something wrong with me.... I'm off to the pub. 

2 comments:

  1. Luke, check out Larus fuscus graellsii

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  2. Never considered graellsii but did consider Herring x LBBG for sometime and to be honest still considering it now.

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