On the cue for male territorial site selection in the dragonfly,Nannophya pygmaea: A field experiment

Abstract

A field observation of the dragonflyNannophya pygmaea revealed that males prefer some territorial sites to others, and that these same sites attract more females than others (Tsubaki & Ono, 1986, 1987). In this paper, we asked if males choose territorial sites in response to female dispersion or distribution of resources. We conducted 3 types of removal experiments to test the following 2 hypotheses; (1) a male may assess the territory quality by the female encounter rate at his site (learning), (2) a male may assess the resource quality (or quantity) in the territory. The results of our experiments show that males discriminate attractive and less attractive territorial sites without any mating experience within the study area. Moreover, the territorial site preference of males was not affected by the mating experience. Therefore, males probably choose territorial sites by resource quality rather than by female dispersion.