An interesting method of catching dragonflies

In 1961 1 made a business trip to China as an employee of a metallurgic company. Once, a bus in which I was traveling stopped near a small rice field. 1 was fascinated by the following scene. A boy, aged about 13, was standing at the edge of a shallow water reservoir, holding a live libellulid dragonfly tied to a black thread (cf. Fig. I). It was flying, vainly trying to free itself. A large number of aeshnids and libellulids were flying over the rice field. From time to time one of them came to the captured dragonfly as close as 15-50 cm, stopped in its flight watching the tied insect, and then departed. There was something inhuman in this tormenting a helpless animal, but it occurred to me that this could be an easy method of catching dragonflies.