Did you know dragonflies swim? Not the adults – they’re the colorful flyers who zip around. We’re talking about younger dragonflies.
They spend their childhood submerged underwater. If you caught one in a net at the edge of a pond, you probably wouldn’t even realize it was a dragonfly.
Larva, nymphs and naiads
Dragonflies go through major physical changes throughout their lives, and they look like completely different animals from one stage to the next. The three stages dragonflies go through are eggs, larval, and adult. This is called incomplete metamorphosis. Complete metamorphosis also has the pupa stage between larva and adult. Think of butterflies who hang out as a chrysalis after inching around as a caterpillar. This is the pupa stage.
An immature (young) insect in the larval stage of incomplete metamorphosis is called a nymph. Dragonflies, crickets and grasshoppers are all nymphs at one point. Dragonflies and damselflies have a special name for their nymphs. We call them naiads. This is a cool term, because in Greek mythology a naiad is a spirit that hangs out in water. You’ll notice that the terms nymph and naiad are used here to mean the same thing.
What a look!
Naiads look nothing like the dragonflies that perch on the edge of a swimming pool. In fact, they look like a weird alien creature! They have stocky, hard-shelled bodies, and they sport six legs and the tiny wing nubs on their backs. They’re drab browns and tans, the perfect colors to blend in with the muddy bottom of a pond or stream.
They must have water to live. They breath through gills that are in their butts! They suck water up into their abdomens to breath. A nymph will also squirt out the water to propel themselves forward — what a cool escape maneuver! This is called jet propulsion.
Check out dragonfly nymphs and their cool moves.
Water hunters
Just like adult dragonflys, naiads like meat. They’re fierce predators, and they are not picky! These carnivores will devour anything they catch, including water insects, worms, tadpoles and even small fish.
They trap their prey with the help of their amazing jaws. Just imagine your jaw unhinged like a snake, but then extended out with a hook and sharp teeth at the end! That is how nymphs bring in dinner. When prey swims by, a nymph’s lower jaw strikes out at lightning speed. Think of it like a spork that you extend out and scoop up your food. Watch it in action, but beware that it’s not for the faint of heart!
Shedding their skin
Dragonfly nymphs grow by molting. That is, they shed their exoskeleton and become bigger and bigger with each molt. Naiads go through 10 to 12 rounds of this. It can take several years before nymphs are ready to molt for the final time and emerge as adult dragonflies with wings.
The Forest Preserve District takes on nymphs!
Lockport Prairie is home to some very endangered green-eyed dragonflies called Hine’s emerald dragonflies. To increase their numbers, 30 green-eyed nymphs were recently released into the wild at Lockport Prairie. The hope is that these nymphs will become adults and help grow the population of the endangered dragonflies.
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