Friday, November 18, 2011
The article states that "The bird is common throughout its range, although some studies show it could be experiencing a slight decline because of habitat changes in its nesting range." How do they determine that there is a slight decline in a common bird species population? This was a good question to ask Charley Burwick, the Springfield Master Naturalist bird brain in residence.
He tells me that in addition to biologists that study specific species, much of the data comes from citizen scientists like you and I. Country wide counts conducted yearly can compare the numbers of all species seen. If there is a trend of declining numbers of a species compared to other common birds, this provides good information on the population in general.
Here are the major surveys which involve birders.