Dragonfly

Dragonflies are insects that have long bodies, transparent wings, and large eyes. There are over 5,000 species of dragonflies that are part of the scientific infraorder called Anisoptera.

What do they look like?

Immature dragonflies have six spindly legs, and a body that is only a few times longer than it is wide. They have two fairly big eyes. Some of their mouthparts are modified to shoot forward and grab prey. They breathe water through gills in their abdomen, and can squirt this water out fast to give themselves a quick jet-propelled movement. Adult dragonflies are easy to recognize. They have long thin bodies, very large eyes, and they hold their 2 pairs of wings out flat on either side. Their legs sometimes have many long stiff hairs. Immature dragonflies are usually brown or greenish, and sometimes have algae growing on them. Adult dragonflies can be very colorful, some are red, blue, yellow, or green.

Other Physical Features bilateral symmetry

Where do they live?

Dragonflies are found all over the world. In Michigan there are 114 species

Biogeographic Regions nearctic

native palearctic

native oriental

native ethiopian

native neotropical

native australian

native

What kind of habitat do they need?

Immature dragonflies live in freshwater. They are most abundant an diverse in slow-moving freshwater that has no fish (small streams and ponds) but can be found in many shallow freshwater habitats. Adult dragonflies often stay near water, but sometimes travel away from water while hunting or on migration. They are fast fliers, so they tend to hunt in open areas, not in thick trees or other vegetation.

These animals are found in the following types of habitat temperate tropical terrestrial freshwater

Terrestrial Biomes taiga desert or dune chaparral forest rainforest scrub forest mountains

Aquatic Biomes lakes and ponds rivers and streams

Wetlands marsh swamp bog

How do they grow?

Dragonflies hatch from eggs in freshwater, and spent at least a few months (sometimes several years) as aquatic predators. As they grow they molt (shed their whole skin at once) many times. Once they are big enough, they crawl out of the water and the adult stage emerges from the skin of the nymph. Once they have transformed into the winged adult stage, the stop growing.

Most dragonfly species spend the winter as nymphs in the water, but some migrate south, and spend the winter as adults. In few species that lay their eggs in the late summer or fall, the eggs don't hatch until spring. Dragonflies emerge from the water in the warm months of spring or summer.

Development - Life Cycle metamorphosis

How long do they live?

Dragonflies live for months at least, and some live for several years as aquatic larvae before emerging and living for a few months as adults.

How do they behave?

Dragonflies need sunny warm weather to fly, usually the temperature must be over 65°C. If it is too cold or wet, they hide in vegetation. Adult male dragonflies often establish territories along the edges of ponds or streams. They only defend the territory against other males of their species. Some large dragonfly species migrate south to warmer climates at the end of the summer. Their offspring may then migrate north the following year.

Key Behaviors diurnal motile nomadic migratory solitary territorial

How do they communicate with each other?

Adult dragonflies communicate visually much more than most other insects. Males fight aerial duels for territory, displaying their size and speed to each other. Mating pairs probably communicate by touch, possibly chemically too

What do they eat?

Dragonflies in their aquatic stage eat many kinds of small animals: aquatic insects, tadpoles, small fish, and other invertebrates. Adult dragonflies eat flying insects, especially mosquitoes and other true flies, but also aphids, smaller dragonflies, damselflies, and just about any other insects they can grab.

Primary Diet carnivore

eats terrestrial vertebrates eats non-insect arthropods

What eats them and how do they avoid being eaten?

Immature dragonflies avoid predators by hiding, and by jetting away if they have to. Adult dragonflies avoid predators with their quick and agile flight, and hide in vegetation when it is too cold to fly.

Known Predators

frogs

fish

large spiders

insect-eating birds

What roles do they have in the ecosystem?

Dragonflies are sometimes the top predators in ponds with no fish. Adult dragonflies help control populations of mosquitos and other flies.

How do they interact with us?

Dragonflies help control populations of biting flies like mosquitos.

Ways that people benefit from these animals: controls pest population

Are they endangered?

Most dragonfly species are abundant and common, but a few use special habitats as immatures, and they are at risk because their habitats are in danger.

IUCN Red List [Link]

Not Evaluated

Some more information...

There are some old stories about dragonflies stinging or stabbing people. They are not true. Dragonflies are totally harmless to people.

Because dragonflies are insects they have 6 legs, a thorax, a head, and an abdomen. The abdomen is long and segmented. Despite having 6 legs, the dragonfly doesn't walk very well. It is a great flyer, however. Dragonflies can hover in one place, fly extremely fast, and even fly backwards. They are some of the fastest flying insects in the world reaching speeds of over 30 miles per hour.

Dragonflies come in a variety of colors including blue, green, yellow, and red. They are some of the most colorful insects on the planet. They also come in a range of sizes from half an inch long to over 5 inches long.

Where do dragonflies live?

Dragonflies live throughout the world. They like to live in warm climates and near the water.

What do they eat?

One of the best things about dragonflies is that they like to eat mosquitoes and gnats. They are carnivores and eat all types of other insects too including cicadas, flies, and even other smaller dragonflies.

To catch their prey, dragonflies create a basket with their legs. They then swoop in capturing their prey with their legs and biting it to hold it in place. They will often eat what they have caught while they are still flying.

In order to see predators and their food dragonflies have large compound eyes. These eyes are made up of thousands of smaller eyes and allow the dragonfly to see in all directions.

Fun Facts About Dragonflies

Dragonflies don't sting and generally don't bite people.

They have been around for 300 million years. Prehistoric dragonflies were much larger and could have a wingspan of 2 ½ feet!

When first hatched, the larva or nymphs live in the water for around a year. Once they leave the water and begin to fly, they only live for around a month.

People in Indonesia like to eat them for a snack.

Having a dragonfly land on your head is considered good luck.

They are not really related to common flies.

Groups of dragonflies are called swarms.

Watching dragonflies, similar to bird watching, is called oding which comes from the order classification odonata.

Predators that eat dragonflies include fish, ducks, birds, and water beetles.

They need to warm up in the sun during the morning before taking off and flying for most of the day.

http://www.biokids.umich.edu/critters/Anisoptera/

http://easyscienceforkids.com/all-about-dragonflies/