The GBBC has been held annually since 1998. This year's four-day event will be February 18-21. According to the GBBC website, www.birdsource.org/gbbc/ the event "engages bird watchers of all ages . . . [in creating] a real-time snapshot of where the birds are across the continent. Anyone can participate, from beginning bird watchers to experts." The minimum amount of time required for someone to qualify is 15 minutes of bird watching on one day. The most enthusiastic participants make counts for up to several hours every day. Since the dates include a Friday and a Monday, school classes could participate during a 15-minute recess. Or a class assignment for Monday could be for children to bring in their list of birds seen over the weekend.
The GBBC website lets you submit your bird counts online. By entering your zip code and state, you can download a printed list of the birds you can expect to find in your area. During last year's GBBC, 97,000 checklists were submitted by people who counted birds at backyard feeders, during walks in their neighborhood or local park, or in natural habitats. To find out exactly what bird watchers in your area and others saw in previous surveys go to the Explore the Results section on the website.
Some biologists criticize the use of amateurs instead of professional ornithologists for collecting data because of a lack of scientific rigor. But the website's guidance on how to conduct the surveys reduces the potential for error. For example, in the 2010 count, 53,513 of the submitted checklists included a sighting of one or more northern cardinals for a total of 265,608 individual birds from 40 states. I would certainly trust anyone to be able to properly identify a big red bird with a crest on its head. And if the limitations of amateurs are taken into account, the bird censuses can unquestionably be useful in detecting some widespread changes in bird populations that might go unnoticed in regional studies.
Comparisons of species records within and between years and localities, which are accessible on the website, reveal some notable trends in distribution and abundance of species and provide information on the changing patterns of how different bird species move across the North American landscape. For example, comparing the number of bird species counted last year in Alabama (169), South Carolina (199), and North Carolina (183) with counts from Minnesota (98), Michigan (115), and Massachusetts (129) supports a supposition--more birds prefer the South during winter than the North. You can also select a bird species and see where it was distributed one year compared to another or compare the geographic sightings of one species with another.
Each state report includes a map showing where previous GBBC participants were located; not unexpectedly the highest concentrations were in urban areas, with many rural areas not represented at all. Caution must be taken, therefore, in interpreting such data, as birds that visit backyard feeders are more likely to be recorded than those that keep to forests and other areas uninhabited by people.
A link to the Cornell Lab of Ornithology assists in bird identification with excellent pictures, descriptions of behavior and habitat, and a sound recording of many native species. An added bonus is information on bird feeders and seed preferences. Despite the limitations of a survey of this nature, the far-reaching effort to keep track of one component of our environment is to be commended. So mark your calendars for February 18-21 and join GBBC 2011. This is an opportunity to participate in a truly worthwhile effort. Happy counting!
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