Food and Feeding: The adult dragonfly is able to catch most of its prey while flying. It plucks insects out of the air with its legs. The dragonfly is rarely still, and its huge, multifaceted eyes enable it to detect prey up to 40 feet away. Almost any flying insect is suitable prey. The dragonfly eats small insects even while it is flying but takes larger prey to a resting perch. The emperor dragonfly’s larvae also hunt. They propel themselves through their underwater habitat by expelling water rapidly from their intestines. Their extendable jaws, armed with deadly hooks, enable the larvae to catch and kill such food as water lice and nymphs. The shovel like jaw of the larva is used to capture a variety of freshwater animals. The legs form a basket in which insects are caught in flight and then transferred to the jaws to be eaten.

Habits: The male emperor dragonfly is almost continuously airborne, in search of a mate or prey that may stray into its territory. The dragonfly’s territory is always over a freshwater pond or lake. The defending dragonfly will attack the trespasser immediately by flying under him to force him up and away from the water. The green and brown female stays away from the water until she is ready to breed, so she is sighted less frequently.

Lifecycle: Most of the dragonfly’s life is spent underwater as larva. It emerges as a winged adult for a few weeks a year to mate and lay eggs. Usually mating takes place in the high branches of a tree along the pond’s bank, but sometimes it will occur in the air. The male pursues the female until he is able to settle on her back. The mating procedure is known as the “copulation wheel.” The female fertilizes the eggs, then uses her ovipostor (a special egg laying organ) to lay them. To protect her eggs from being eaten by fish, she places them into slits that she has cut into stems of pondweed.

The eggs develop in about 3 weeks, depending upon the temperature of the water. The larva, or nymph, that hatches is wingless and lives in the water. It molts (sheds its skin) ten to fifteen times during the 2 years it takes to mature. Almost all of its growth occurs in summer months. In the last stage of development the larva crawls out of the water and dries its skin in the sun. As the skin splits, the adult dragonfly emerges. Once its soft wings have hardened, it can fly. The adult dragonfly lives for only a few brief weeks. The lifecycle of the emperor dragonfly guarantees that its larvae hatch at the same time, allowing a better chance for the adults to breed successfully.

Naturewatch: The emperor dragonfly is usually recognizable by its large size. The male has a deep blue abdomen, divided by a central back stripe. Its head is green. At close range it can be identified by the distinctive rounded inside edges of the hind wings. The female is green and brown and is much less conspicuous than the male. During summer the adult male patrols its territory – weedy ponds and lakes. It usually flies 6-20 feet above the water. When it does rest, it perches briefly on the edge of a reed bed or in a tree. Adults can be found near any stretch of unpolluted fresh water in their range. Larvae emerge from the water as early as May.

Key Facts:
Sizes:
Length: Adult, 3 in.; larvae, 2in.
Wingspan: 4 in.
Coloration: Adult male; enable blue body with central black stripe and green head; adult female: green head and greenish body.
Wings: 2 pairs, moved independently

Breeding:
Eggs: Cream colored and elongated; laid in plant stems
Hatching time: 3-4 weeks

Lifestyle:
Habit: Active hawker
Diet: 
Adult: winged insects; nymph: invertebrates, tadpoles
Lifespan: Adult, about 4 weeks; nymph, 2 years

Related Species: A subspecies of Anax imperator occurs in southern Africa.
Distribution: The emperor dragonfly is found in Europe, the British Isles, North Africa, the Middle East, and Northwestern India.
Conservation: The dragonfly is extremely susceptible to the effects of water pollution and drainage. Its future depends on the survival of clean, unpolluted ponds, lakes, and waterways.

Special Features of the Emperor Dragonfly: The larva has an extended jaw armed with hooks. It pushes them forward to catch and kill its prey. The male uses calipers at the tip of his abdomen to grip the female’s thorax. The male transfers sperm from the tip of his abdomen to accessory sexual organs. The female then fertilizes the eggs.
The copulation wheel: the female arches her body under the male to mate. They may fly in tandem while they are mating.

Did You Know:
Dragonflies always rest with their wings spread open.
Dragonflies and their larvae are a popular food in some Asian countries.
There are over 30,000 facets in a dragonfly’s eye.
Very few birds can outfly and hunt down dragonflies. The fast flying, agile hobby is a match.
The dragonfly’s front and hind wings beat alternately, not together, as with most insects. This gives them better flight control.

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