The National Audubon Society's annual Christmas census of birds across America -- including the Quad-Cities area -- is under way.
The count is meant to measure the health of bird populations, according to the Society. Data on how birds are doing can be used to help establish what challenges they, and the ecosystem they inhabit, are facing.
Locally, the count has helped show the effect of habitat loss on grassland bird species and changes in the migratory habits of some robins, according to Janelle Swanberg, president's of the Society's Quad-Cities chapter. It also has helped shed light on the increase in bald eagle populations and the effect of West Nile Virus on crows and other birds.
"If we tally the number of crows, we can see if they are making a comeback or not," Ms. Swanberg said.
The Christmas Bird Count was started in 1900 by Frank Chapman, an ornithologist at the American Museum of Natural History, according to the Audubon website. He hoped it would be an alternative to a kind of hunting game called a "side hunt."
In the side hunt, a group of people would form into competing teams and the team to bring back a larger kill would win, according to the website.
From Mr. Chapman's initial count, the program has spread throughout the United States and has found its way to Canada, Mexico and portions of South America, according to the Society.
A region where a count is taking place is divided up into circles that are 15 miles in diameter. A group counts all of the birds it sees in one circle on a specific day, according to the Society. To participate, there is a $5 fee for most observers older than 18.
Counters who go into the circle to find birds are grouped together, according to the website.
"One of the real benefits of the count for people is that novice birders can go out with experienced birders and really learn a lot," Ms. Swanberg said.
If they do not wish to join a group, participants in a circle can count birds at their feeders but must check in with the organizers for the area ahead of time, the website states. Observers watching feeders do not have to pay the fee.
The count began Dec. 14 and will run through Jan. 5.
Wildlife biologist Kelly McKay, who compiles the data for the Quad-Cities area, said results will not be available until after the count concludes and could not provide any preliminary data on Tuesday.
Walt Zuurdeeg, 52, of Davenport, said he has been participating in the counts for years.
Mr. Zuurdeeg said his count this time has been lower than in previous years, and he said he suspects the weather: The weather is mild, meaning there is more territory in which birds can find food.
Bald eagles eat fish and tend to cluster around open water in the otherwise frozen Mississippi River, he said. This year, there is no ice, freeing the birds from that restriction.
Mr. Zuurdeeg said he enjoys nature, the challenge of identifying birds and keeping records of the birds he sees -- what bird enthusiasts call listing. He starts a new list each year, though listing technique varies based on the preference of the enthusiast.
"Each year I start fresh," he said.
More information about the Christmas Bird Count can be found on the Audubon website at:
Today is Friday, Dec. 13, the 347th day of 2013. There are 18 days left in the year. 1863 -- 150 years ago: Merry sleigh bells jingle in our streets in the wake of a driving northwest storm of snow and rain. 1888 -- 125 years ago: Thomas Campbell was elected commander of John Buford Post 243, Grand Army of the Republic. 1913 -- 100 years ago: Thomas B. Reidy was named consul of C.W. Hawes Camp No. 1550, and L.H. Eihl was named consul of Camp 29, Modern Woodmen of America. 1938 -- 75 years ago: Rock Island aldermen last night upheld the view of a petition signed by 150 businessmen that the city should not install parking meters. 1963 -- 50 years ago: Total volume during the Christmas mailing season may reach 12 million pieces in Rock Island, according to Rock Island Postmaster Carl J.L. Wessel. 1988 -- 25 years ago: The aromas filling the air at the Rock Island Lines depot in Rock Island soon will be prime rib and roast duck rather than sawdust and plaster. A tourist train will be offering dinner excursions in mid-February or early March, according to Dan Carmody, executive director of the Development Association of Rock Island.