Hey all, meant to post this ages ago, it's from a workshop with Glenn and David back in February.
I was pretty excited by this sequence, getting some foot action as well was nice.
I'll echo Chris' comments. It's the fact that line of rocks/water is so close to and skimming the Turnstone's head and body. Although hard to follow through in the field, getting lower (if possible) to get the head and neck completely in the blue area would have been ideal. I see why you like the foot action...I do too!! Good sharpness as posted, and good job on the exposure - both the whites and the blacks look good.