Underwater denizens of your backyard pond: Dragonflies

 

 

Hello all, your Friendly Neighborhood Biologist here to enlighten you on an often-overlooked creature that patrols the depths of your pond and the skies of your calm summer evenings.

 

Dragonflies.  

 

Dragonflies (and damselflies) are members of the order Odonata and are REALLY COOL!!!!!

 

Squadrons of these insect attack helicopters swoop through swarming mosquitoes, defending us from the stinging bites of insectile nuisances.  Along with bats, dragonflies eat more mosquitos by weight than any other insectivore. Then (of course) there are species of dragonflies eat other dragonflies…. Why is this, well because Mother Nature is weird that’s why….

Living on every continent in the world (except Antarctica), there are 7000+ species worldwide.  These aerial experts can fly up to 35mph and spring from a truly ancient lineage.  There are fossil records of dragonflies going back 325 million years!

These avian defenders of our skies feast and mate all within a single summer, most only living for a few weeks.  Once matured, they lay their eggs back in the water from whence they came and proceed to shuffle off this mortal coil, completing a job well done.

It came from the DEEP!

I personally find the time they spend under the waves fascinating. Dragonfly larvae (called Naiads or nymphs) are underwater predators as well.  Even as kids, Dragonfly nymphs scurry about the submerged rocks and underwater vegetation, hunting other aquatic insects and even some small fish.  These creepy-looking hunters lurk around the depths for up to 5 years (though most of the time it’s less than three), just waiting for the right time for their season in the sun. 

 

 

Ready for a weird, kinda gross fun fact?  It’s fantastic, I promise……

 

Dragonfly nymphs breathe through gills in their butt (rectum).  No lie! 

 

Another cool fact…. Using their butt gills, they can quickly squirt (heh) through the water by shooting a jet of water out of their anus…. SWEET! Butt jet propulsion!!!!!    😉

 

***ASIDE: This process is similar to when a certain Lakes Biologist has too much spicy Mexican food… Ahem***

 

Moving on…..

 

Location, Location, Location:

 

Finding these denizens of murky depths can be a challenge as they blend into the rocks and decaying vegitative matter that they like to call home.  Turn over submerged stones, or scoop out some dead leaves or even live aquatic plants.  Take that pile of detritus to a clear surface to examine your catch.  Dragonfly nymphs look like the pictures above….. here’s some more:

 

You most likely also find a myriad of other aquatic insect trucking about in your aquatic sample. These critters exist near the base of the aquatic food chain and can tell you a lot about the environment that they live in. 

Dragonflies are a part of a diverse pond/lake ecosystem.  They are indicators of good or degraded water quality.  The species present in your backyard can tell an observant pond manager how good/clean the water source is.  Installing and maintaining an aerated ecosystem will attract more species of Dragonflies (among many other organisms) and increase the overall ecological potential of your pond. 

 

Single Diffuser Aeration System

2 – diffuser Aeration system

Aerating Fountains

 

A balanced and diverse underwater community maintains itself.  There is much less need for nutrient controls and algae treatments due to natural competition for resources within a balanced food web.  

 

Along with a good aeration system, augmenting your lacustrian domains with beneficial bacteria is always a step in the right direction. These bacteria strains improve water quality and degrade organic matter, creating better habitat for all sorts of organisms. 

 

6# Bacteria Block

Liquid Bacteria

 

Dragonflies, like most insect species right now, are in decline.  It is not known what the culprit is for this, but it most likely has to do with climate change, loss of suitable habitat, and Chicago Cubs fans.  

Enjoy your pond, strive to make it better using the tools we have available to us, and please look around below the waterline.  There is an entirely new/different world beneath the waves; alien forms and interesting life cycles happening mostly without anyone of us noticing.  Kick over some rocks, or examine some of your underwater plants.  This type of habitat is vital to the unseen organisms that call your pond home.  

 

Please feel free to continue onto our webpage (Midwestponds.com) or continue reading more of my articles about pond biology (Water’s Edge Blog). I love to answer pond questions, so send messages along anytime.  In the meantime, go out and enjoy your pond.

 

Joe Cadieux

Senior Biologist

Midwestponds

 

 

 

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