This adult Lesser Black-backed (surprisingly scarce up there, our only LBB of the trip) caused me quite a stir when I 1st saw it swimming around in the open hole. Aftr nothing but white-headed Great Black-backs, while looking for the heavily-marked Slaty-back, the swimming Lesser initially had me thinking Slaty-back. The legs weren't visible, and it would have been obvious here, but the hunt briefly got the best of me. It finally dawned on me what this bird probably was, and finally it got out so the bright yellow legs were visible.

Luckily, we got the Slaty-back here shortly afterwards.