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USGS · 5210239

Techniques and results of nongame bird monitoring in North America

C.S. Robbins·D. Bystrak·P.H. Geissler
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Abstract

Long-term bird population trends based on accumulated ratios (proportional change) sometimes give a very misleading view of population change. Alternate methods of representing population change, based on the weighted means for the individual years, avoid the dangers of using ratios. Some advantages and disadvantages of various weighting techniques are discussed.

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C.S. Robbins, D. Bystrak, P.H. Geissler. 1980. Techniques and results of nongame bird monitoring in North America. https://pubs.usgs.gov/publication/5210239

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