Yellowlegs: Lesser or Greater?

 As the Meadow Grounds Lake recedes mud flats are being exposed.  The exposed lake bed in turn is attracting some species of bird life not normally seen when the lake is at full pool.  Such was the case last Saturday when I spotted a pair of Yellowlegs feeding near the north end.

 The first image captured the bird as it probed under the water and a moment later it had some type of bug or beetle grasp in its bill.

 

While I can identify the birds as yellowlegs I am unsure whether they are greater or lesser yellowlegs.

And the same goes for this group I captured running across a salt flat at Assateague Island during our October visit.  Any help with a positive ID on these birds will be much appreciated.