2010 Great Backyard Bird Count results

Count records more than 600 bird species across North America
April 2010. The 13th annual Great Backyard Bird Count (GBBC) results are in and it was a record-breaking year for participation. During the four-day event in February, more than 97,200 bird checklists were submitted by an estimated 63,000 volunteer bird watchers from across the United States and Canada. From reports of rare species to large-scale tracking of bird movements, the GBBC provides insight into the lives of bird populations.

American robins most numerous
For example, this year, participants recorded more American Robins than any other bird species-primarily because of a massive roost in St. Petersburg, Florida. Participants reported 1,450,058 robins in Saint Petersburg alone. For perspective, the entire rest of the continent tallied 400,321 robins. Reports such as these help document hotspots for robins and year-to-year changes in their movements across the continent.

Where are the Pine siskins and redpolls?
At the other extreme, one of the most dramatic results from this year's count was the absence of other bird species, including winter finches such as Pine Siskins and redpolls. Pine Siskins moved south in such great numbers last year that they burst onto the GBBC Top-10 list of most numerous birds for the first time ever. Over time, the GBBC has captured dramatic swings in the numbers of these species reported from year to year. These fluctuations may be influenced by the birds' food supply and reproductive success far to the north. This year, they presumably didn't need to travel as far south to find enough food.

Invasive Collared dove spreading across the continent
Results from this year's GBBC also documented the continuing expansion of an introduced species across the continent. A dozen years ago, the Eurasian Collared-Dove was reported in 9 states during the GBBC. This year more than 14,000 doves were reported in 39 states and provinces.

Tree swallow increase
Tree Swallows showed dramatic increases in numbers reported compared to years past. Although the number of states reporting the species was down from 25 in 2009 to 20 this year, the number of individuals reported increased nearly four-fold, from 22,431 to 84,585. Whether this is a result of warmer temperatures and earlier migration is not yet clear.

Unusual sightings - Red-billed Tropicbird
"The new and the unusual are always a thrill during the GBBC," said Robert Petty, Western Director of Field Support at Audubon's Education and Centers. "Notable sightings this year included a Crimson-collared Grosbeak in McAllen, Texas--the first time the species has been reported during the count since 2005." Birders off the coast of San Diego were treated to a Red-billed Tropicbird-the first verified sighting of this species for the Great Backyard Bird Count. Highlights from Canada included a Rustic Bunting seen in Creighton, Saskatchewan. In Marathon, Ontario, a Gray-crowned Rosy-Finch was a spectacular sighting because it was far outside its normal range in the Rocky Mountains.

"GBBC data become more and more valuable with each passing year," said Dick Cannings, program director for 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."
The GBBC is a joint project of the National Audubon Society and the Cornell Lab of Ornithology with Canadian partner Bird Studies Canada. It is open to bird watchers of all ages. The results provided a snapshot of the whereabouts of more than 600 bird species. "There's simply no better way to collect information about all these birds so quickly across such a large range," said Janis Dickinson, Citizen Science director at the Cornell Lab.

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