Contribution of dragonflies to the regulation of arthropod communities
Established at the UBC Farm in May 2020
Project Leads
Rassim Khelifa (Post-Doctoral fellow), Faculty of Science
Claire Kremen (Supervisor), Faculty of Science
Funding
Postdoctoral mobility fellowship from the Swiss National Science Foundation
About the Project
Dragonflies play a crucial role in the regulation of insect populations in aquatic and terrestrial systems. As adults, they have a high dispersal ability and occupy a wide range of habitats during foraging, including agricultural lands. The diet of dragonflies has not been well studied and their contribution to the regulation of insect communities in agricultural ecosystems is not well understood. Most of what we know is that dragonflies have been observed to eat a large array of insects that are smaller than them. In this project, we will assess the diet of dragonflies in UBC Farm and try to determine their effect on the populations of pollinators, pests, and/or their natural enemies. Thus, we aim to characterize the services and disservices dragonflies provide in agricultural ecosystems.
Research Questions
- What do the diets of local UBC Farm dragonflies consist of?
- Do dragonflies affect farm levels of pests, pollinators, and/or their predators at UBC Farm?
Methods
Using transects and hand nets on crop field’s edges, the researchers will carefully capture dragonflies in nets, which will then be transferred to a small plastic bag, where the dragonflies will defecate and then been released. This waste will be used to identify the prey eaten by the dragonflies. Movement of dragonflies and foraging areas will also be monitored by attaching light transmitters on the dragonflies’ thorax; this will allow us to track and gather information on local dragonfly behavior and spatial distribution here at UBC Farm.
Project expected impact
Data gathered will fill an existing knowledge gap surrounding the agricultural impacts of dragonfly’s diets on the regulation of local insect communities. If the study proves that dragonflies play an important role in crops pest control, as hypothesized, the project results have the potential to help promote eco-friendly agriculture by increasing the habitat elements that attract dragonflies in agricultural settings.
Interesting fact: Dragonflies primarily consume insects as part of their diets. The use of wide-range insecticides can drastically affect the dragonflies’ ability to feed and survive.