Field identification of individual Little Bustard Tetrax tetrax males using plumage patterns.

Full article

Published:

Volume 46(1), June 1999. Pages 51-60.

Language:

English

Keywords:

field technique, individual recognition, Little Bustard, phenotypic characteristics, Tetrax tetrax.

Abstract:

We examine the variability in phenotypic characteristics in Little Bustard Tetrax tetrax males to determine which are the elements that better allow individual recognition throughout a season. Six variables were chosen, for which individual variations could be classed into clearly distinguishable categories and for which all categories were well represented among the males present in our study population. These variables were: continuity of the white collar across the nape, colour pattern of the throat, symmetry of «V» white collar, the relative width of the black and white breast bands, the frequency of black dots on the mantle, and iris colour (Fig. 1). The combination of these six variables reliably allowed the individual recognition of all Little Bustard males (up to 55) in our study area throughout the breeding season at distances of up to 250 m with the aid of binoculars and telescopes. In areas where it is necessary to identify a much larger number of males, the addition of an extra variable would diminish the probability of two males having the same combination of variables.