There is something really cool about dragonflies. Most other flying insects bite, sting, or pester you. Dragonflies just seem to be in a class all their own. Want to know more about these amazing critters? Glad to hear it.
First the Stats…
Now the cool facts
1.) In their larval stage, which can last up to two years, dragonflies are aquatic and eat just about anything—tadpoles, mosquitoes, fish, other insect larvae and even each other.
2.) Currently about 5,000 species of dragonflies and damselflies are known; experts guess that there are probably between 5500 and 6500 species in total! All of these (along with damselflies) belong to the order Odonata, which means “toothed one” in Greek and refers to the dragonfly’s serrated teeth.
3.) Dragonflies were some of the first winged insects to evolve, approximately 300 million years ago.
4.) Modern dragonflies have wingspans of only two to five inches, but fossil dragonflies have been found with wingspans of up to two feet.
5.) Dragonflies can fly straight up and down, hover like a helicopter and even mate in mid-air. If they can’t fly, they’ll starve because they only eat prey they catch while flying.
6.) Dragonflies catch their insect prey by grabbing it with their feet. They’re so efficient in their hunting that, in one Harvard University study, the dragonflies caught 90 to 95 percent of the prey released into their enclosure.
7.) At the end of its larval stage, the dragonfly crawls out of the water, then its exoskeleton cracks open and releases the insect’s abdomen, which had been packed in like a telescope. Its four wings come out, and they dry and harden over the next several hours to days, and grow as they dry.
8.) Dragonflies catch their insect prey by grabbing it with their feet. They’re so efficient in their hunting that, in one study, the dragonflies caught 90 to 95 percent of the prey released into their enclosure.
9.) Some adult dragonflies live for only a few weeks while others live up to a year.
10.) Hundreds of dragonflies of various species will gather in swarms, either for feeding or migration. Not much is known about this behavior, but the Dragonfly Swarm Project is collecting reports on swarms to better understand the behavior. Have you ever seen a swarm?
11.) Scientists have tracked migratory dragonflies by attaching tiny transmitters to wings with a combination of eyelash adhesive and superglue. They found that green darners from New Jersey traveled only every third day and an average of 7.5 miles per day (though one dragonfly traveled 100 miles in a single day!)
12.) Dragonflies have near-360-degree vision, with just one blind spot directly behind them!
13.) What does a dragonfly eat? Insects, as adults, and they are a great controller of the mosquito population. A single dragonfly can eat 30 to hundreds of mosquitoes per day.
14.) One dragonfly called the globe skinner (Pantala flavescens) has the longest migration of any insect. It flies approximately 11,000 miles back and forth across the Indian Ocean!
15.) One research team has determined that the nervous system of a dragonfly displays an almost human capacity for selective attention, able to focus on a single prey as it flies amid a cloud of similarly fluttering insects, just as a guest at a party can attend to a friend’s words while ignoring the background chatter.
16.) Thankfully, dragonflies can’t bite humans. The vast majority of species don’t have mandibles strong enough to break the skin. Only a small handful of large species are capable of actually biting, but this only occurs as a defensive strategy.
Humans have what’s known as tri-chromatic vision, which means we see colors as a combination of red, blue and green. This is all thanks to 3 different types of light-sensitive proteins in our eyes, called opsins. We are not alone: di-, tri- and tetra-chromatic vision is the norm in the animal kingdom. A study of 12 dragonfly species has found that each one has 11, and some a whopping 30, different visual opsins!
17.) Some species of dragonfly, such as the seaside dragonlet (Erythrodiplax berenicei) can successfully produce offspring in water much saltier than the ocean.
18.) What enemies does the dragonfly and damselfly have? Birds, spiders, frogs, and larger dragonflies. In the larval stage, they are preyed on by fish, frogs, toads and newts, and other water invertebrates; including other dragonflies.
19.) The giant forest damselfly (Megaloprepus coerulatus) of Central America has a wingspan up to 19 cm (7.5 in)! The bulkiest known dragonfly is the giant petaltail (Petalura ingentissima) from Australia, with a wingspan up to 16 cm (nearly 6.5 in)!
20.) It is estimated that the top speed for a dragonfly is between 30 and 60 km/h (19 to 38 m.p.h.). The maximum flight speed varies much between different species, with bigger dragonflies generally flying faster than smaller ones.
Dragonflies may have hunted across the planet for the last 325 million years, but their modern relatives are looking extinction in the face. Experts warn that 1/3 of British species alone are now under threat, a plight that today sees the opening of the UK’s first ever dragonfly center to celebrate and protect one of the country’s most fascinating insects. This center was opened recently.