This weekend marks a milestone for Martha’s Vineyard birders, who will be fanning out across the Island Saturday in the 60th Christmas Bird Count.

An estimated 60 or more bird enthusiasts, organized into 13 teams with captains, are expected to participate in this year’s count, which begins before dawn when the owls are still abroad and lasts until sunset.

The goal for the day is to identify and catalog as many bird species as possible, noting how many of each have been spotted together. At the end of the day, the results will be tallied up at a 5:30 p.m. meeting at the Wakeman Center in Tisbury.

Backyard birders can also take part in the bird count by noting what species come to their feeders, along with the highest number seen together for each species, then emailing the list to mvbirdcount@gmail.com on Saturday.

Bird lists can also be phoned in to 800-690-0993 extension 0 between 1 and 4 p.m. Jan. 4, when a volunteer with Island nonprofit BioDiversity Works will take them down.

The Christmas bird count is a nationwide National Audubon Society observance that began in 1900 and gradually made its way to the Vineyard, where some years of unofficial counts resolved into an organized annual effort beginning in the winter of 1959-1960.

Among those earlier bird counts, a 1951 Gazette article reported that in 1932 a team counted the last living heath hen.