Guide for use
While many parameters can be extracted from calls and have been reported in the literature, not all are useful for species identification. "One problem that all the sciences face is what to measure, and the history of science is littered with examples of measurements that turned out not to be useful." Krebs, C.J. 2014. Ecological Methodology.
The 9 call parameters presented here as a reference are those most frequently reported are provided for comparison. Many parameters such as BW, TBC, varied slope measurements and Fmax are highly variable and affected by the distance of the bat from the microphone; among other aspects of the physics of sound.
Users are urged to consult the glossary for details of each parameter. The dominant harmonic of the characteristic frequency, Fc is generally the second harmonic, H2 and is one of the most robust parameters for identification.
These parameters have been selected from all of those extracted from call files using AnalookW. A summary of descriptive statistics is provided. These include the minimum, maximum, standard deviation and range of values usually encountered. The commonly measured 75% and 90% range of values from pulses measured (N) provide a guide. Not all parameters are necessary for identification and in many cases the dominant harmonic Fc is all that is necessary. In a few cases species that have overlapping Fc values but differ in other parameters require one or more additional parameters to be used.
After deriving a tentative identification from the interactive ID keys, it is useful to return to the fact sheets to review the species selected for additional details..
Be aware that it is not always possible to identify species from acoustic data 100% of the time.
Copyright © Bruce W. Miller, Cynthia S. Marks and George E. Marks
Chris Corben contributed to the glossary,2021, all rights reserved.