Monday, December 9, 2013

The Annual Christmas Bird Count

The Barred Owl can be found throughout the winter
Of all the possible times of year to choose from, why conduct a bird census in December? That’s the most common question people ask when they hear about the Christmas Bird Count. In December, and in wintertime in general, there are the fewest number of bird species to be found in the Northeast. Yet, this is when approximately 30 Mohawk Valley residents brave the cold to participate in the National Audubon Society's Annual Chistmas Bird Count. Once all of our individual field sheets are tallied, we can expect to confirm between 50 and 60 bird species in the greater Utica area. That's not bad considering that any one of us during the course of a normal winter day might expect to find no more than 10 species in our own yards.
The female Northern Cardinal  - a bird for all seasons
Most Northern Flickers head south, but a few will remain each winter 
The Christmas Bird Count is the longest running bird census in North American. It began in the year 1900 and was conceived by ornithologist Frank Chapman as a protest against the once popular Christmas wildlife shoot (called a Side Hunt) that used to take place annually on Christmas Day. The object of Side Hunts was for teams of hunters to go out in the field and shoot as many birds and small animals as they could find. Each animal was assigned a certain number of points and the team with the most points at the end of the day was declared the winner. Unfortunately, birds and other animals were the guaranteed losers in these events. It’s important to understand that this was happening at a time before strong Federal laws protected our native birds. Such an event would be illegal if it were to be held today.
The most numerous bird found on last year’s count was the Snow Goose
Blue Jays are one of the staple birds our local count
Before the Federal Migratory Bird Treaty act went into effect in 1918, many North American bird species appeared to be headed toward extinction. Some, like the Passenger Pigeon and the Carolina Parakeet, had already gone extinct.  Side hunts were by no means the main cause of the declines; a whole range of pressures from market hunting to habitat loss to egg and specimen collecting all took their toll. One of the greatest single threats came from the Plume Trade. Between 1880 and 1920, decorating women’s fancy hats with elegant bird feathers was a fashion imperative that frequently drove Plume hunters to decimate entire nesting colonies of Egrets, Terns and other species in search of beautiful feathers.
The Sharp-shinned Hawk preys on winter songbirds
In the beginning, very few people participated in the Christmas Bird Count and in only a few places, mostly in the Northeastern US. Over the course of many decades its popularity grew exponentially.  Today, tens of thousands of birdwatchers participate in 2,300 counts that take place all over North America. The census data that is collected is useful because it gives scientists a snapshot of where birds are at a specific time of year. By comparing results across multiple years, they can draw conclusions about how species and specific populations are changing over time. 
The Tree Sparrow is our quintessential winter sparrow

Where there is open water you may find Hooded Mergansers
The protocol for counting birds is the same whether you are in Alaska or in Mexico; participants are tasked with counting every bird they see on a single pre-determined date. Most counts take place from dawn to dusk but nighttime birding, in the form of “owling”, is also encouraged. All bird counters must stay within a designated count circle that is 15 miles in diameter. For the Clinton/Utica Bird Count, the center of our circle is roughly where Jay-K Lumber is located on Seneca Turnpike in New Hartford. Our circle contains a diverse range of habitats, everything from forestland to agricultural fields and from marshes to city streets. Each distinct habitat type has the potential to harbor different kinds of birds.
If there is open water, some Wood Ducks may be found
Over the 40 years that the Clinton/Utica Christmas Bird Count has been taking place, we have seen some significant changes in the bird life of the Mohawk Valley. Probably the most notable change has been the number of waterfowl that are now regularly found lingering here into mid-December. That trend began in the 1990s and has become more dramatic as the years have progressed. A species like the Snow Goose that was never encountered in our count circle until the year 2000 was the most numerous bird species tallied in our most recent count. Last year, close to 70,000 of them were seen in area cornfields and flying overhead. Warmer temperatures in December are enabling these geese to migrate later in the season than before. Canada Geese and a variety of ducks are now expected to be found since open water and snow-free farm fields often remain available through at least mid-December.
The House Finch was once one of our most common winter birds
Local Christmas Bird Count data tracks significant changes in the populations of some our common backyard songbirds. For example, the House Finch never occurred in Central New York until the 1970’s after which their numbers gradually increased and finally hit a peak in the early ‘90s. Following that, their numbers crashed. The drop in population was the result of a form of conjunctivitis (an eye disease) that proved deadly to the birds. The disease spread like wildfire in this highly social species that commonly feeds together in flocks. After the 1990’s, modest numbers of House Finches continued to be tallied on our bird counts but their numbers never again reached their former highs. To this day, the disease remains a limiting factor in their population. 
Once rare, the Red-bellied Woodpecker is now quite common
Once common, now the Red-headed Woodpecker is rarely seen locally
The Red-bellied Woodpecker is a species that was never found in our count circle until 1980, when a single bird was located.  In contrast, we regularly see as many as 30 of them now, which makes them as common as any other of the regularly occurring winter woodpeckers. This change can be explained by the regrowth of forests in our region.   The Red-bellied Woodpecker is a forest nesting species that benefits greatly when agricultural fields give way to woodlands. The increasing popularity of maintaining well stocked bird feeders has also benefited the Red-bellied Woodpecker, since they are quick to utilize those resources.
The fortunes of the Red-headed Woodpecker are quite different than those of its Red-bellied cousin. Once, the Red-heads were a common species in the Mohawk Valley, but by the time the Clinton/Utica Christmas Bird Count got started in 1974, the species was already on its way out. Still, individuals and small groups continued to be found within our count circle until 1990. The reasons for the Red-headed Woodpecker’s decline are not fully understood, but it is thought that the same alteration in the region’s habitat that benefited the Red-bellied Woodpecker was a disadvantage to the Red-head, which requires more open land in order to thrive.

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