Nearly 2 million robins ruled the roost in the 2010 Great Backyard Bird Count, outnumbering all other species in the 13th annual tally of North American birds reported by 63,000 volunteer bird watchers.
The large number of American robins was mainly because of a massive roost in St. Petersburg, Fla., where birders reported 1.4 million during the four-day event in February.
…In addition to robins, the most numerous birds were Canada geese, snow geese, American crows, and European starlings.
...“GBBC data become more and more valuable with each passing year,” said Dick Cannings of Bird Studies Canada. “Over time we’ll be better able to see significant changes that may occur in the numbers and distributions of birds which may be tied to climate change, habitat loss, disease, or other factors.”