Dragonflies and damselflies (the Odonata) are among the most efficient flying insects. However, fragmentation of the landscape can increase distance between habitats and affect costs of dispersal, thus shaping phenotypic patterns of flight-related traits, such as wing shape, wing loading and wing size. Urban landscapes are highly fragmented, which limits dispersal among aquatic habitats. Hence,
Although the sex ratio of Odonata at emergence has received much attention, we are still far from understanding the exact causes of its variability and imbalance. In this paper we studied the sex ratios at emergence in natural populations of two Gomphus species based on samples of exuviae taken from two European lowland rivers. We
We studied a population of Polythore procera along a stream in the Colombian eastern Andean foothills. Mark and recapture samples were made during January to April 2006, covering both dry and wet seasons. We determined population size, daily survival probability, and longevity during the entire period and compared them with precipitation data. Age and sex…
Populations of Ischnura hastata found in the Azores archipelago represent the only known example of parthenogenesis in the order Odonata. In this paper, we present results from fieldwork done on the islands of São Miguel, Pico, Santa Maria, and Graciosa, aimed at characterizing population ecology and habitat preferences of this species. Sampling of several ponds…
Progomphus obscurus is one of the most abundant dragonflies in South Carolina, USA. We collected dragonfly larvae from 127 sites in the Enoree River and nine of its tributaries, and correlated the abundance of P. obscurus larvae with physical and chemical characteristics of these streams. As expected for this burrowing species, larval abundance varied among…