Publications and Products
Order a printed copyof this publication.
Research Note
Title: Optimizing the duration of point counts for monitoring trends in bird populations
Author: Verner, Jared
Date: 1988
Source: Res. Note PSW-RN-395. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 4 p
Station ID: RN-PSW-395
Description: Minute-by-minute analysis of point counts of birds in mixed-conifer forests in the Sierra National Forest, central California, showed that cumulative counts of species and individuals increased in a curvilinear fashion but did not reach asymptotes after 10 minutes of counting. Comparison of the expected number of individuals counted per hour with various combinations of counting time and noncounting times (for record keeping and travel between counting stations) showed that 10-minute counts were most efficient in most cases. Counting longer than 10 minutes is not recommended, because of the increased risk of double counting some.
Keywords: birds, monitoring, point counts, count duration, Sierra Nevada
View and Print this Publication (359 KB)
Citation
Verner, Jared 1988. Optimizing the duration of point counts for monitoring trends in bird populations. Res. Note PSW-RN-395. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 4 p.