Insects: Guarded oviposition - damselflies

Damselflies mating
Photo copyright Gloria Z. Nagler

Text and photos by Gloria Z. Nagler

I happened upon these two bluets (damselflies) at a local pond the other day. According to Merrill Peterson in his oh-so-useful “Pacific Northwest Insects” book (hot off the press), there are 6,000 species of damselflies and dragonflies in the world — and we in the Pacific Northwest have 117 of those species. Lucky us, indeed — damselflies are both attractive and alien.

As we can see from first photo, the male attaches to the female's head with "claspers" which are located near his abdomen. They then copulate, the female next ovipositing the fertilized eggs into the water (or vegetation in the water). The male stands guard above her during the process, to pull her out if danger comes, and, perhaps more critical to his interests, to defend against other males.

The female's head is underwater
Photo copyright Gloria Z. Nagler

In the second photo, her head is underwater... he pulls her up and out, if she's lucky: and, as is seen in the third photo, sometimes he forgets to detach from her and they fly off in tandem (or he perhaps wants to remove her from the competition — while I watched this pair, at least one other bluet flew by a few times, presumably checking out the female).

They fly off, still attached
Photo copyright Gloria Z. Nagler

Having spent two years as aquatic larvae, or nymphs, some damselflies live only a few weeks as winged adults. Reproduction is now their top priority. Mating lasts less than five minutes in some species, though can take longer in others. The pair I photographed (and thank you to those bluets:), mated for less than five minutes. I had to change position and shoot like crazy to get the shots! Some stay connected up to 7 hours -- phew!

Sources: Pacific Northwest Insects, by Merrill A. Peterson; and Discover Wildlife, from BBC Wildlife Magazine (“Understanding damselfly behavior”).