PROVIDENCE, N.Y. | Thousands of citizen scientists across North America are getting out their tally sheets for the 13th annual Great Backyard Bird Count, a usually festive weekend given a more serious edge after the deaths of thousands of birds in the South this winter.
The National Audubon Society and Cornell Lab of Ornithology sponsor the count. They hope to have more than 100,000 backyard counters for the effort this Friday through Monday, especially after public attention on threats to birds was heightened when blackbirds fell from the sky in Arkansas on New Year's Eve.
"An isolated event such as the dead birds in Arkansas may be within the range of normal ups and downs for an abundant species like the red-winged blackbird," said Janis Dickinson, director of citizen science at the Cornell lab in Ithaca. "But the count can serve as an early warning system for worrisome declines in bird populations that result from more widespread problems."
The deaths in Arkansas — where officials suspect the birds were spooked by fireworks — and subsequent bird kills in Tennessee, Kentucky and Louisiana aren't thought to be connected or a sign of widespread contagion.
The backyard count is one of a number of citizen-science projects that gather data on birds. Others are Aubudon's Christmas Bird Count, the North American Breeding Bird Survey and Cornell's Project FeederWatch and NestWatch.
"One thing we anticipate this year is the presence of birds from the boreal forest of Canada, such as common redpolls, at feeders in the Northern U.S.," said Cornell's Miyoko Chu. "They stay up North when they can find enough seeds, but this year birders are seeing them at their feeders."
In the Northeast, where much of the landscape is buried under deep snowdrifts, American robins are likely to be scarce, based on data from previous years showing that they tend to avoid areas with heavy snow cover, Ms. Chu said. Although robins traditionally are considered harbingers of spring, many winter up north but stick to thickets where they feed on dried berries and fruit.
Participants, including novice and expert bird-watchers, keep track of the number of birds they see of each species in their yards or local parks during the four-day count and report the data online at www.birdcount.org.
Counters in Arkansas aren't expecting that the birds lost on New Year's Eve — about 5,000 specimens of the abundant red-winged blackbird — will affect their results, but they acknowledge the die-off is on their minds.
"When it comes to trends in bird populations, you've got to look at the long term," said Dan Scheiman of Audubon Arkansas. "That's what's so great about the Backyard Bird Count: It can produce long-term trends over large scales."
Lois Geshiwlm and Nancy Castillo, owners of Wild Birds Unlimited in Saratoga Springs, participate in the backyard bird count and several other citizen-science programs each year from their log home surrounded by feeders stocked with seed, suet, peanut butter and other treats.
"I like to think of the Great Backyard Bird Count as the every-person's science project," Ms. Castillo said. "It's the easiest one for the real casual bird-watcher to step in for one day a year, or four days a year, to count the birds."