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Lurking in your lake: What bugs are in lakes, rivers. Should people take caution?


When you look out across the placid waters behind your cabin, you might wonder what insects are lurking just below the surface. If insects are included in a horror film, they are inevitably portrayed as villains. Indeed, even within the insect world, bugs are vicious remorseless killers. Before you dive right in, you might want to know what insects are sharing the water.

Good insects to find while swimming:


The Caddisfly: Though they might be irritating when they emerge from the water in the millions, caddisflies are neat insects. They spend most of their life underwater eating plant material that has fallen into the river or lake. The larval form might be ugly, yet it is quite resourceful. It can create a home made out of small twigs, rocks or anything else they get ahold of. If you have caddisflies in a tank of water and sprinkle in precious gems, they will make an expensive home. Caddisflies are good because their presence mean the water in which you are swimming is clean. In the realm of biology, caddisflies are considered to be an indicator species. If water has pollution, they die.

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The Dragonfly: If you think that the mighty dragonfly is a creature of the air, think again. The dragonfly lives most of its life beneath the water as a nymph that eats hundreds of other insects. The largest dragonfly nymph will even eat a small fish. You have nothing to worry about this hungry larva. You are much too big and the dragonfly nymph will find smaller prey to fill its hunger. Dragonflies are good in both stages. They eat mosquitoes by the mouthful. Without the amazing dragonfly, the number of disease ridden mosquitoes would be infinitely grater. (And you thought the number of mosquitoes was bad now.)

Take Caution:

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The Toe-biter: With a name like that, you know it means trouble. Coming in at nearly the size of an adult hand, it is little wonder that the toe-bitters other name is the Giant Water Bug. Before you run away from the water screaming, the toe-biter will only bite you if you are stupid enough to mess with the massive insect. Though you won’t die if they bite you, their bites are considered to be among the most painful from the insect world.

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Dobsonfly: The Dobsonfly larva is referred to as a hellgrammite for good reason. This critter is the picture of hideous insect. Much like the toe-biter, it is not out to get you. If you decide to both one of these insane looking insects, it can deliver a bite that can break the skin. If you leave the dobsonfly alone, you never have to worry about getting bit. One thing that is good about the Dobsonfly is they are a water quality indicator. Though not as good as a caddisfly, if you find them in the water you know the water lacks pollution.