Possible white-rumped sandpiper Hale

I was at Hale lighthouse for 5:45am this morning, hoping to connect with a broad-billed sandpiper which was seen yesterday. The light was perfect, and the 500 or so dunlin and ringed plover showed  really well at close range. The black bellies of the dunlin in breeding plumage were very convenient and made scanning through the flock quite a quick job, because basically I was looking for a bird with a white belly. It was fortunate that I could scan quickly, because the birds were very flighty and often flew up and over the river before returning to the same spot to feed.

I'd scanned through the flock several times and hadn't managed to pick out the broad-billed sandpiper. I couldn't completely rule it out, because there were large parts of the mud which I couldn't see and the birds were flighty, but I was pretty sure it wasn't there. I scanned again, and immediately picked up a bird with white belly which was smaller than the dunlin which I hadn't seen before. It clearly wasn't the broad-billed sandpiper, and nor was it a stint, apart from anything else it just wasn't small enough for a stint, I would say that it was intermediate in size between dunlin and stint. It had a shortish, straight bill, was very horizontal compared to the dunlin and I was struck by how grey it looked, especially on the primaries. I immediately called it as a white-rumped sandpiper, but then doubts began to creep in and I wondered about Baird's This all happened within just a few seconds and then the bird disappeared behind some vegetation and never reappeared. A couple of minutes later the flock flew again, some disappearing to the left, others returning to the same spot. I scanned again several times but couldn't relocate the bird.

Having now refreshed my memory on the differences between Baird's and white-rumped sandpiper, I'm pretty confident that it was the latter and certainly one or the other, but unless it gets seen again I'm affraid that it's likely to be the one that got away, good enough for my personal records but not likely to make it onto the county list. Oh well, get out there and find it again someone please! Hale shore is obviously worth checking around high tide at the moment.