37 observataion points were set up in different locations throughout the Plum Island estuary and adjacent Essex Bay. Bird counts were carried out biweekly in 2012 and weekly in 2013 from May through the end of September. One coutn was carried out in July 2014
Counts were carried out randomly with respect to tide and time of day. The whole area could be sampled in two days (approximately 6 hours per day) by one team of observers.
Although the focus of the study was on Snowy and Great Egrets, observers counted all the birds visible from each observation point and recorded the following information:
1. species and number,of individuals. Species was recorded using the American Ornithologists Union accepted alpha code (http://birdpop.org/pages/birdSpeciesCodes.php)
2. the estimated distance in meters from the observer in concentric bands from the observation point (0-100m and >100 in 2012, 0-100, 100-250, 250-500, 500-1000, >1000 in 2013 and 2014). Most of these estimates were assisted by rangefinder binoculars
3. the number of birds in different habitats (marsh, tidal flat, pannes, open water, rock)
4. the number of birds engaged in different behaviors at each habitat (feeding, resting, preening, alert).
5. Birds flying over the observation area were recorded separately as flyovers

Counts of wading birds and shorebirds in coastal wetlands from vantage points

Raposa, K.B., R.A. McKinney, and A. Beaudette. 2009. Effect of tide stage on the use of salt marshes by wading birds in Rhode Island. Northeastern Naturalist 16:209-224.