Dunlin doing impression of curlew sandpiper?
No interactions present.
I think these are Curlew Sandpiper - they look too long in the neck for Dunlin
There is nothing in this photo that would suggest that Curlew Sandpiper was more likely than Dunlin to be the correct ID for these birds, and going from this single photo I would call them Dunlin.
They do look longer necked than you would normally expect Dunlin to appear, but both birds look alert (perhaps aware of, and watching, the photographer).
Compare with the top photo, of a summer plumaged Dunlin, here; http://www.birdguides.com/iris/pictures.asp?mode=search&sp=57080&rty=0&r... (there is another long necked looking Dunlin four photos down).
Good point, and wouldn't be very confident about my hunch - that said, from the evidence of this single picture (with not a lot of plumage detail visible) I'm not sure there is enough for certainty either way. I find the obvious 'longer neckedness' to be a good field character, especially in poor light etc.
Have added a second shot of the same birds, this time including a scale object
The lower bird on the second shot does look a bit like a curlew sand, especially the eyestripe (supercilium). But then a lot of dunlins look like curlew sands and vice versa. With confusion species like these two most birders have a particular feature that they look before they make a decision - sometimes called a clincher. With curlew sands I never feel happy unless I can see their beautiful scalloped back feathers. Scalloping is a characteristic pattern on a number of birds created by each feather having a perfect pale edging - ruffs have it as well. Curlew sands ALWAYS show it, dunlins NEVER show it. So it's a fail-safe way to identify them. No scalloping here.
Lat/Lng: 52.967043, 0.666237
OS grid ref: TF791444