Dragonflies complete their early development in aquatic habitats and then emerge into a flight-capable adult form. Because body size and morphology are fixed at the point of transition into the adult form, changes in the aquatic developmental habitat can affect adult morphology as well as their behaviour. We are experimentally investigating how climate change and warmer aquatic environments will alter the growth and development of juvenile dragonflies and how warming affects adult size, morphology, and dispersal behaviour in these insects. We focus on dispersal behaviour because of its central role in connecting populations, structuring communities, and allowing species to respond to climate change. The effects of warmer aquatic environments on adult dispersal behaviour in dragonflies can therefore have broad-reaching impacts on the populations, communities, and conservation of these insects and the communities in which they are embedded.
Additional Scientific Information
We will use dragonflies to examine how carry-over effects between life-history stages (aquatic larvae to aerial/terrestrial adults) can cause local developmental conditions to affect dispersal behaviour and ultimately regional connectivity. We will rear dragonfly larvae in 378L mesocosms (cattle tanks) that are warmed to varying temperatures (ambient to +5°C). These tanks and the associated heating system will be located on the northern section of the eastern tennis court. We will monitor larvae in these tanks and measure growth and survival throughout their developmental period. In spring 2014 these established tanks will be covered with mosquito nets to allow dragonflies to emerge into these nets where they will be collected, measured, and marked. Marked dragonflies will then be released and we will follow their movements to ponds on KSR and to 24, 1300L cattle tanks (established in spring 2014) distributed at varying distances from the central ponds across KSR to serve as “pond” habitat. We will also use translocations of adult dragonflies to assess how local habitat and matrix conditions affect dispersal behaviour in these animals.
Principal Investigator: Shannon McCauley