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Keith Arnold

Publication Date

6-1-2003

Abstract

Christmas bird counts have been in existence for over a century; in Texas, the “oldest” count exceeds 50 years. Counts which have a long history of regular occurrence can give us an idea of changes in bird populations within that count circle. These can include increases such as occurred with Cattle Egret, White‑winged Doves and Eurasian Collared‑Doves and House Finch, or decreases as with Greater Roadrunner and Northern Bobwhite. Increases and decreases may reflect actual changes in those avian populations or habitat changes within the circle, usually from increased urbanization. By examining count results on a larger scale, we can determine actual population changes over time and habitat changes. Finally, CBCs do occasionally document the occurrence of rare and unusual species. Unfortunately, the count data have a number of inherent problems, misidentification of which is not the least. Too many counts exert more time and energy on compiling a species list, while taking a more cavalier attitude towards actual numbers. In addition, in cases where two similar species occur in a count circle, one finds that every individual of thousands are identified to species! Even though the data with each count includes numbers of participants, weather conditions, etc., we do not know how thoroughly the area of each count was covered nor if all habitats received apportioned time in relation to the percent of habitat. Other problems exist.

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