Like other dragonfly species, the Subarctic darner has a complex lifecycle which includes a fully aquatic larval stage (2). As larvae or ‘nymphs’, dragonflies are effective sit-and-wait predators with the fascinating feature of being able to fire out the lower portion of the mouth, known as the ‘mask’, in order to grasp passing prey (2) (7). As well as being able to walk, dragonfly larvae are able to move through the water by jet propulsion, expelling water from a specialised rectal chamber to propel themselves along (2).
The total length of time spent in the larval stage varies between dragonfly species, with some species spending a few months and others several years as a larva (2). The larva undergoes several moults before finally emerging from the water as the readily recognisable adult dragonfly (2) (7). The adult Subarctic darner is active between July and September (2).
Dragonflies are skilled aerial predators, typically feeding on small insects caught on the wing (2) (7). When not in flight, most members of the genus Aeshna tend to rest in a hanging position, rather than flat like other species of dragonfly (2).