Standard breeding bird censuses with 50 m radius counting circles.  Observing periods divided into 0-3 min, 3-5 min, and 5-10 minutes for comparison with other censuses.  For 3-5 min period, only additional birds not recorded in the 0-3 period are recorded.  For 5-10 min period, only additional birds not recorded in the 0-5 min period are recorded.  Birds recorded either visually or by sound.  Counting circle boundaries set a minimum of 200 m from each other.  Counts carried out from late May through early July with most counts in June.  Placement of circles encompassed a variety of habitats.

Counting circles located on Plum Island and cover the length of the Parker River National Wildlife Refuge on the island from near the entrance booth at parking lot 1 to Stage Island Pool.  Counting circles set up in close proximity to the refuge road.