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Damselflies and dragonflies make up the insect order Odonata. For anyone who has walked past a dam in summer the mating process is probably very familiar. Males patrol and aggressively defend a territory of water. After he attracts a mate, the male will grasp the female behind the head with claspers on the end of his abdomen. Pictured left are two Aurora Bluetails (Ischnura aurora) in that position.

Mating occurs when the female curls her abdomen underneath the male and picks up the sperm from a location where the male has previously placed it (see picture right). This is called the heart or wheel position. The pair will then fly in tandem, with the male still grasping the female behind the head while the female deposits eggs on submerged plants. In this way the male ensures that his sperm is used to fertilise the eggs, because if the female is left alone other males can scrape out the sperm of a previous male and deposit their own.

I have observed many damselfly pairs land on the appropriate vegetation so the female can deposit the eggs on underwater stems and leaves (pictured left). I recently witnessed an extraordinary display of stamina, when over the course of an hour a female dragonfly grasped and laid eggs on several different submerged stems. During the entire time, the male remained in flight and fended off continuous attacks from other males (right). The mating game out there is tough!

Just some more Odonata data for you.