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Depending on the species and the quality of the habitat, they spend anywhere from one to six years in the nymph stage. When the nymphs mature, they climb out of the water and hang onto a cattail leaf or other water plant. The nymphal skin splits along the back and the adult dragonfly emerges. The old nymphal skins can often be found still clinging to the plant. Adult dragonflies are also predaceous and often catch their prey on the wing. I've seen them feeding on butterflies, large flies, other dragonflies, and spiders. I once saw a dragonfly so intent on eating a jumping spider that he failed to notice another jumping spider which crept up behind and made him into a meal! Some behaviors you might notice in dragonflies are perching, patrolling, chasing, fighting, mating, and egg laying. Male dragonflies are territorial; they defend territories which females find favorable for laying eggs. You will see males patrolling their territory, perching where they can keep an eye on things, chasing other males away, and even fighting with other males in the air. The mating position of dragonflies is unusual; it is called a wheel. The male grasps the female behind her head and she inserts her abdomen into a sperm receptacle on the underside of his abdomen, near where it attaches to the thorax. They may perch or fly in this position. Some males continue to grasp the female behind her head after mating; they fly in tandem and the male dips her abdomen into the water, while she lays eggs. I did a survey of the dragonflies at the pond on July 8 and 11, 2005. Note that males and females of the same species often look quite different.
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