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Black Backed Gulls (1 Viewer)

Can anyone give me a simple way to distinguish between Great and Lesser Black Backed Gulls apart from size?
Just look at the bill structure of GBBGULL, a very deep and heavy affair, LBBGull is almost dainty by comparison.

Cheers
 
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if the bird is fully adult, p10 (outermost primary) has a large all white tip and p9 has a large, square 'mirror', so there's a lot of white in wingtip. LBBG very rarely has an all white p10 tip and p9 mirror (if present) is small. leg colour also in 95% decisive with pinkish in GBBG and bright yellow in LBBG (adults!). structure: GBBG has short primary projection - distance of tips of primaries to tail tip is less than distance between tertial tips to tail tip. in flight, wings of GBBG are proportionally broader, long and pointed in LBBG. In western populations (ssp. graellsii of LBBG) mantle tone of LBBG is clearly paler than that of GBBG. Most adult GBBG have dark irides, LBBG pale ones.
lots of pics:
LBBG: http://www.gull-research.org/lbbg1cy/0start.html
GBBG: http://gull-research.org/gbbg/0start.html
 
If it has yellow legs is is definitely a Lesser.

On the other hand, if it has pink legs it could be an adult Greater or a subadult lesser. But you will soon be able to tell the difference just on the different general build and look of the two birds.
 
nobody buys field guides these days ( joking)
I wish it was a joke! Trouble is that people first look for advice they can get for free, go straight to the internet (like what one does for anything these days), and - because it gets them somewhere - think that's the way to do it. What they then miss out on is the huuuge amount that you can learn from a field guide - preferably a printed one - a book! The boon for usability and utility is such that you just can't imagine if you've never had one. Modern beginner-birders are thus so so losing out.
 
I wish it was a joke! Trouble is that people first look for advice they can get for free, go straight to the internet (like what one does for anything these days), and - because it gets them somewhere - think that's the way to do it. What they then miss out on is the huuuge amount that you can learn from a field guide - preferably a printed one - a book! The boon for usability and utility is such that you just can't imagine if you've never had one. Modern beginner-birders are thus so so losing out.
Apologies for asking too simple a question. I do have field guides but sometimes looking in a book doesn't always compensate for actual expertise.
So I wasn't looking for free advice, just some interaction with other birders.
But I respect your view all the same.
 
nobody buys field guides these days ( joking)....rather post and wait for a n other to identify it
I do. Most birders I know also get a new one for each part of the world they visit, so they can learn about the birds they hope to see in advance and recognise some when they get there. I have a bookshelf or 3 full. Most birders not only have them but annotate them to add other info. Also, I have to quite a few places around the world, and most rangers, or nature guides have several, covering many many topics. More and more people are downloading birding apps, so they always have something with them.
 
Apologies for asking too simple a question. I do have field guides but sometimes looking in a book doesn't always compensate for actual expertise.
So I wasn't looking for free advice, just some interaction with other birders.
But I respect your view all the same.
There is nothing simple about Gull recognition. It is a specialist subject that many fear to take on. MakePlansjer_Engelsk.pdf is a useful quick guide made extremely simple and worth a look.
 
Apologies for asking too simple a question. I do have field guides but sometimes looking in a book doesn't always compensate for actual expertise.
So I wasn't looking for free advice, just some interaction with other birders.
But I respect your view all the same.
I’ve been into this for about a year now and as a bit of a newbie I totally get this. Honestly, i’ve pretty much avoided gulls until recently and I struggle with these two birds at the moment unless they are close up and obvious. But I know it will become more and more obvious with practice.
I remember when I first started I’d taken a picture of a Meadow Pipit not knowing what it was. And even when I was staring at books and pictures online, and comparing, I absolutely could not decide whether it was a Meadow Pipit or a Skylark! Now when I see that picture it seems so obvious! I actually feel kind of embarrassed! Haha but that’s how it is I suppose, you need to develop a familiarity first before being able separate them by their differences, especially with very similar birds.
 
Size, Great-black backed Gull is enormous.

The legs on GBBG are pink, those of LBBG are yellow.

GBBG has a bill like a meat cleaver.

The mantle and wings on an adult GBBG are darker than those on the adult LBBG in Britain.

David
 
Size, Great-black backed Gull is enormous.

The legs on GBBG are pink, those of LBBG are yellow.

GBBG has a bill like a meat cleaver.

The mantle and wings on an adult GBBG are darker than those on the adult LBBG in Britain.

David
Not always as clear cut as some of these suggestions. It's not uncommon for LBBG to have fleshy coloured legs in winter though true breeding adults have bright yellow legs.

Also regarding mantle/wing colour- many intermedius winter here which approach the darkness of GBBG, though it's true our breeding graellsii birds have more smoky grey colour.

Agree size & bill should enable easy ID for a not too distant bird.
 
Well, that was a bit of a rollercoaster! Much obliged to you all.
As an aside my son in Australia (South of Melbourne), who is also a bird enthiusiast, just sent me this photo of a bird in his neighbours garden.
It's a Tawny Frogmouth so he informs me.
 

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