Birds

Birds

Chapter 9 Birds 9.1. Complete Counts 9.1.1. Entire Sampling Frame 9.1.2. Portion of Sampling Frame 9.2. Incomplete Counts 9.2.1. Index Methods 9.2.2...

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Chapter 9

Birds 9.1. Complete Counts 9.1.1. Entire Sampling Frame 9.1.2. Portion of Sampling Frame 9.2. Incomplete Counts 9.2.1. Index Methods 9.2.2. Adjusting for Incomplete Detectability

9.3. Recommendations 9.3.1. General Comments 9.3.2. Dichotomous Key to Enumeration Methods Literature Cited

There are a variety of techniques used to obtain distribution, abundance, and productivity estimates for avian species. No method can be universally applied to all species or populations because of the variety of both statistical and practical problems associated with different situations. Detailed information on survey methods may be obtained from reviews of counting techniques for songbirds (Verner, 1985; Wiens, 1989; Manuwal and Carey, 1991), raptors (Fuller and Mosher, 1981, 1987; Kochert, 1986), waterfowl (Eng, 1986a; Cowardin and Blohm, 1992), colonial waterbirds (Speich, 1986), upland gamebirds (Eng, 1986b), and all birds (Call, 1981; Bibby et al.y 1992). Andrews and Righter (1992) described distribution and habitat use of birds in Colorado. In this chapter, we describe a variety of counting techniques for birds so that the reader may choose the technique that best fits his or her research objectives and requirements. We cover index methods for use in an index monitoring program (gathering general information on species status) as well as techniques for obtaining valid estimates of spatial distribution and abundance/density for use in an inferential monitoring program (i.e., one in which some average change in population can be reliably detected). This chapter concentrates on methods for counting breeding birds because these 261