학술논문

Does the use of playback affect the estimated numbers of red–legged partridge Alectoris rufa?
Document Type
article
Source
Animal Biodiversity and Conservation, Vol 35, Iss 2, Pp 429-435 (2012)
Subject
Red–legged partridge
Census technique
Playback
Underestimation
Population monitoring
Raw count data
Zoology
QL1-991
Language
English
Spanish; Castilian
ISSN
1578-665X
Abstract
The red–legged partridge Alectoris rufa lives in a situation of potential conservation risk for its long–term preservation in Italy as its habitat is increasingly threatened by the disappearance of traditional agriculture–related environments. In such a situation, it is important to use effective and appropriate monitoring methods to assess population changes over time and to identify potential conservation threats. The objective of this study was to evaluate the effectiveness of the playback method to estimate the density of calling males. We compared playback method with spontaneous calling of males at dawn and direct observations along transects. The results on raw count data of playback counts revealed a strong underestimation rate compared to the method that gave the best results: count of spontaneous calls at dawn. Our study provides a critical evaluation of a method that is widely used even though data about its effectiveness are scarce. Our data do not evaluate detection probability of the three methods. Our aim was only to evaluate which methods give the best results in term of population size estimation under the same field condition (same population density, same period, same monitoring area). The results raise some doubts about the ability of the playback method to monitor red–legged partridge populations. The implications of our results for red–legged population management are discussed.