Mark-Recapture Studies on Co-Occurring Sympecma Fusca (Vander Linden, 1820) and S. Paedisca (Brauer, 1877) (Odonata: Zygoptera: Lestidae)

Maturation cohorts and reproductive cohorts of the two Sympecma species were studied in Chomutov (Czech Republic) from 2010 to 2013. During individual mark-recapture studies, a total of 705 winter damselflies were recorded, 473 of which were individually marked (375 S. fusca, 98 S. paedisca). The recapture rates in the maturation habitat and in the reproductive habitat were low. The population estimate using CHAPMAN's method for low recapture rates could not be carried out separately for the two species owing to the low recapture rate of S. paedisca. The proportion of females was greater in the maturation habitat and significantly lower than that of males in the reproductive habitat. The reproductive habitat was predominantly inhabited by territorial males. All the females observed there were engaged in reproductive activities. There was a close correlation between the male density along the shoreline and reproductive activities. S. paedisca was less abundant than S. fusca. No differences between the two species were observed in reproductive behaviour. However, S. paedisca appeared to disperse continuously away from the maturation habitat. Perhaps this species prefers more open areas as maturation and wintering habitats. S. fusca was observed here until October.