What plover/sandpiper?

[belliott]

I know next to nothing about shorebird ID and need help with these. 

My guess is some kind of sandpiper--although American Golden-plovers have been observed in the general area.

Please ID and explain why.

Southwest Missouri today, with numerous yellow-legs in a mud puddle in a farm field.

Thanks

https://www.dropbox.com/s/nbtplqkvlawcau2/PLOVER-SANDPIPER BIRD 2021-04-13 4-31-18 PM_2.JPG?dl=0

[Avery]

You are right that these are sandpipers and not plovers. The long, thin bill and smaller size helps with that. The yellow legs and small structure, as opposed to something like a yellowlegs, also narrow it down to a few options: Pectoral and least. Others are ruled out by range. From there, I am having trouble. I’m not even sure if these are all the same species. The orange base to the bill makes me think Pectoral, but I cannot see the breast of many of the birds. It’s been a while for shorebird ID for me, but I’ll be getting a refresher next week!

[Hasan]

These are all Pectoral Sandpipers.

[IKLland]

2 hours ago, Hasan said:

These are all Pectoral Sandpipers.

I don't have pectoral experience, but why aren't those least sandpipers?

[Connor Cochrane]

44 minutes ago, IKLland said:

I don't have pectoral experience, but why aren't those least sandpipers?

Body shape is one way to tell, least are never that tall. The orange base to the bill is also a good hint. In person they are much larger than Leasts.