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How Bugs in the Mud Help Keep Waters Clean

Have you ever wondered why you never see baby dragonflies or mosquitoes flying around? A lot of baby insects look very different from their adult forms, and many don’t even live on land! The young insects, or larvae of dragonflies, mosquitoes, and many other insects are aquatic, meaning they live in water. These young bugs are also a huge help for scientists who check up on ecosystems’ health.

What kinds of bugs live at the bottom of lakes and rivers?

The rocks and mud at the bottom of a stream may not look like much, but if you look closely, often these areas are filled to the brim with fascinating critters! If you go to the shore of the bay and scoop up some mud or flip over a rock, you can usually find any number of critters crawling and oozing their way through the water. Familiar animals like dragonflies, mosquitoes, and mayflies live out most of their lives as larvae underwater. Mayflies are famous for their short adult lifespans of less than a day, but did you know that they can live as aquatic larvae for up to 2 years?

All kinds of tiny worms, bugs, and snails live in the water, and most of them are perfectly harmless to people! As well, they can also be a big help to us in looking after our wetlands.

How can bugs help us keep our wetlands “healthy”?

Of course, we want our river, pond, and lake ecosystems to be healthy. After all, a healthy body of water makes for good fishing, swimming, and sightseeing. All kinds of tiny plants and animals work together to clean the water and stop diseases from spreading. Even though we can’t see it, wetlands do so much for us! This is a good reason why we must keep them healthy – but what does “health” even mean for an ecosystem?

A healthy river or pond is one that is clean from pollutants and undisturbed enough to have all kinds of different plants and animals in it! An easy way to tell if a river system is healthy is by looking at how many kinds of animals live in it. This is why we can use animals – bugs!! – to check up on wetland ecosystems! We can look at the number and types of bugs in the water to check up on the water. If the water is polluted, you will only be able to find a few kinds of bugs that can live with the pollution. On the other hand, if there are lots of different kinds of bugs, we can tell that the wetland is probably very clean and healthy! Next time you’re out by the water and you find a strange-looking critter on the underside of a rock, don’t be afraid! There’s a whole world of critters just below the surface, and they can tell us a lot about the environment they live in.

The young forms of insects are called “larvae”! Can you spot the mayfly larva on this rock? Credit: Wikimedia commons
It may not look like it, but this big bug is a young dragonfly! Credit Wikimedia Commons/Ian Alexander

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