[Control of male density in the dragonflyAeschna cyanea (Odonata) : An analysis with a systems theory approach].

Mature males of the dragonflyAeschna cyanea visit a pond several times a day for mating. The individuals arrive in a random manner, but the density of the males at the pond varies little. The males at the pond are described as a system which has the property of regulating male density, by a feedback mechanism involving interaction of 2 behavioural parameters: the number of fights between the males increases with their density and a male's visit is shorter when there are more fights (Fig. 12).