Do climate changes influence dispersal and population dynamics of dragonflies in the western Peruvian Andes?

Abstract

For nine dragonfl y species (fi ve aeshnids and four libellulids) all previous and verifi able data are related to the vertical climate zones and nature regions of the western Peruvian Andes and the Peruvian Pacifi c coast. Climate changes due to the El Niño and La Niña phenomena, as well as the global climate change have an infl uence on the diff erent natural regions and also restrict aquatic biotopes. Th ese changes infl uence the dispersal and behavior of some dragonfl ies and concern also loss of habitats as well as alterations of biotic and abiotic factors at and in water. However new waters and habitats also are formed in most nature regions. Specialists like Rhionaeschna peralta, a species of high mountain regions and the Puna, are not able to react to habitat losses by adapta- tion, while other species such as R. maita and R. marchali do colonize new habitats also in higher altitudes. While the here represented aeshnids change their distribution ranges within the vertical nature regions of the west Andes, this is suspected for three of the four libellulids (Orthemis ferruginea, O. discolor and Pantala fl avescens) as latitudinally respectively longitudinally immigrations and expansions of their areals. For all species discussed, a seasonally earlier fl ight beginning is detectable, but for no species an exten- sion of their fl ight time. Altogether, the above named three libellulid do react more fl exibly and faster to the alterations by climate changes than the majority of the fi ve aeshnid species. Th e infl uence of increased UV-B and UV-A radiation possibly aff ects also the site occurrence of some species in high altitudes of the Andes.