Herring or GBB Gull? (1 Viewer)

[Matt Griffiths]

Hello,
I recently had a very large immature gull fly over my local lakes, which I'm pretty sure was a GBB Gull. Features noted included a thick shortish bill, obviously pale inner primaries, and a black band at end of tail with a second thinner band just in front but broken in the centre, all pointing to GBBG. My only hesitancy in calling it one is that the species is a patch rarity and I've previously had similarly large adult Herring Gulls. Looking at bill size/shape variation in immature Herrings on Google Images, I came across this http://www.birdseyesandbutterflies.com/wp-content/gallery/blog7/herring_gull_immature_1769.jpg with a bill proportionally similar to the bird I saw but it's labelled as a Herring - is this within the range of variation, or is it actually a GBBG?
Matt

N.B. Photo was taken in the USA but I understand both Herring species are very similar.

 

[lou salomon]

hi matt,

the bird in your link looks to be a 2nd cycle (2nd winter) GBBG. note rounded primary tips and short pale tongue at base of p10. bill looks very massive as does the rest of the bird - too bulky for smithsonianus for me.

 

[Matt Griffiths]

Thanks Lou.