Thayer's Week! - the typical problem

And it wouldn't be "Thayer's Week" without a lovely juvenile bird like this. Sure, it looks good for Thayer's (and that's what I'm calling it), but surely there's some Kumlien's in there. 15-20% maybe? Have a look: 

A little weak on all ID features, but they all point to Thayer's (dark wings, darkish (sorta) secondaries, dark centred scapualrs etc). Things like the semi-marbled tertials are also a bit iffy. 

Wouldn't it be fascinating to know what this bird looks like when it grows up? 

Normal logic would suggest the bird will grow up to be a "middle of the pack" Thayer's-ish thing, similar to the bird presented below (posted on the blog last week): 

It is nother bird I'm calling a "Thayer's", since it does seem to fit the bill really for Kumlien's.. . But it ain't exactly perfect... Is this the future of today's (juvenile) Thayer's? Logically it makes sense, but gulls really don't understand logic.

I'm just guessing here, but it would seem almost equally as likely to grow up into a whole new mess. Maybe it could grow up to look like a normal Kumlien's Iceland Gull: 

Or maybe it grows up into a spectacular perfect Thayers:

We really don't know, but it would be awesome if we could.... Can we start catching these things? Would keeping them as pets be bad for them? Would be an awesome study to learn from.......

More Thayer's coming at you tomorrow!