A flock of yellowlegs and sandpipers alltogether. Difficult to tell apart from so far. Yellowlegs, yellow legs extending beyond the body with short bill (lesser yellowlegs), with long bill and slightly recurved (greater yellowlegs). Pectoral sandpiper, yellow legs and legs do not extend beyond the body. 

A flock of yellowlegs and sandpipers alltogether. Difficult to tell apart from so far. Yellowlegs, yellow legs extending beyond the body with short bill (lesser yellowlegs), with long bill and slightly recurved (greater yellowlegs). Pectoral sandpiper, yellow legs and legs do not extend beyond the body.