Dragonflies and damselflies
beneficial, all
Dragonflies and damselflies (Odonata anisoptera; Odonata zygoptera)
Seeing these gorgeous creatures in flight in the garden is a magical experience. Nimble and agile, their translucent wings shimmer above their distinctive long abdomen which ranges from iridescent blue to metallic green, depending on the species.
They are abundant in Saskatchewan: 52 species of dragonflies and 28 species of damselflies have been observed here.
These are beneficial insects you want in your garden: they are top predators when it comes to hunting and killing insects. The adults eat midges, moths and mosquitoes, to name a few. The larvae eat aquatic eggs, larvae and insects – larger dragonfly larvae will even feed on tadpoles and tiny fish.
They lay their eggs in still or running water in spring and their populations do well in wet years when sloughs are full.
Dragonflies and damselflies will also hatch out in ponds and water features in home gardens. Include one or two marshy standing plants in the pond to provide habitat for dragonflies and damselflies to lay their eggs.
A word of caution – if you have a pond or water feature in your garden and are using mosquito dunks containing Bt-israelensis (Bt-i), you may be killing dragonflies and damselflies too. A better way to control mosquitoes is to put fish and/or a pump in your pond.
Sources
http://www.aquatax.ca/odonata.html
http://www.ucmp.berkeley.edu/arthropoda/uniramia/odonatoida.html