Male mating tactics in the American rubyspot damselfly: territoriality, nonterritoriality and switching behaviour

Odonates exhibit a wide range of territorial and nonterritorial mating tactics and are ideal for investigating alternative reproductive behaviours. We studied male mating tactics in the American rubyspot damselfly, Hetaerina americana, a species that exhibits red wing spots that have been suggested to have evolved as a consequence of male–male contests. In this species mating success is enhanced by the ability of males to defend territories along streams and rivers, which depends on the amount of thoracic fat reserves available. Previous studies on this species have distinguished between territorial and nonterritorial males, in which the former obtain significantly more matings than the latter. In our study, however, we found a third reproductive tactic: switching. Switcher males exhibit both territorial and nonterritorial tactics and a mating success similar to that of territorial and nonterritorial males, although this result may be confounded by the small sample size used for this analysis. We suggest that the different mating tactics may be condition determined: territorial males contained the highest fat reserves, nonterritorial males had the least fat content and switchers had intermediate fat loads. We also show that there were no age differences between males using these tactics. Our results suggest that territorial behaviour is extremely plastic in this species. Finally, we discuss the implications of our study and directions for future work on territorial and nonterritorial reproductive tactics in odonates.