Burning Silo

Last Saturday, we hiked a favourite trail that leads over an old beaver dam between two ponds sheltered by high granite ridges. It’s one of our favourite places to go to see many species of dragon and damselflies from spring through autumn.

Long before reaching the pond, we were met by dozens of dragonflies — most being Chalk-fronted Corporal Skimmers (Libellula julia) which tend to be the most numerous fliers in mixed forests at this time of year. We found several other species as well. Alongside the old beaver dam, we found large numbers of dragonflies emerging from their exuviae (see above photo). Many of the dragonflies could be seen clinging to their recently shed exuviae, which in turn, were clasped onto cattail leaves or wide blades of grass just inches above the water.

Often, we found clusters of exuviae - the shed exoskeletons of naiads - within inches of one another as in the photo to the left (click to see larger version). Although outwardly similar, the exuviae of the various dragonfly species may be distinguished by their size and shape.

Depending on species, naiads - the larval stage of the dragonfly - live in water for anything from a few weeks to several years. As they grow, they will molt and shed their exoskeletons many times before finally emerging from the water to molt one last time to become airborne as dragonflies.

After leaving their exuviae, teneral (recently emerged) dragonflies may often be found perched on nearby vegetation as they wait for their wings to harden before flying to their preferred habitat.

The bodies of immature dragonflies are generally pale in colour, often barely resembling the mature adults of their species. The wings are silvery and very translucent, and eyes are pale and milky in appearance (see above photo). As the dragonfly matures, its colours will be more pronounced - often becoming much darker. In some species, markings will continue to change over time. Males of most species tend to be more colourful, while females tend to be drab. Eyes will also darken, often becoming bright green, blue or a rich shade of brown depending on sex and species. The wings of the maturing dragonfly soon lose their silvery sheen, and the veins become darker and more pronounced. In very aged dragonflies, the wings are often tattered or torn, but in most cases, dragonflies manage to fly quite well, even on badly damaged wings.

Tags: dragonfly, teneral, naiaid, exuviae, exoskeleton