They look like little rowboats, cruising belly up below the surface of a pond or gentle stream. But don't be fooled. Backswimmers are voracious predators, and when it's time to find a new home they know how to make a dramatic exit.

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Ever feel like your world’s been flipped upside down? That’s life for these bugs.

Backswimmers are predatory insects that get their name because they spend their lives flipped with their backs facing down and their bellies facing up. They do a kind of backstroke using their oversized back legs like oars.

Spending their time flipped over is convenient because it helps them know if any unlucky prey has accidentally fallen into the water.

“They are vicious predators,” says Kate Boersma, a biologist at University of San Diego, “and they're very fast in the water. They do hunt underwater, but they also eat stuff that falls in. Mostly terrestrial insects.”

Backswimmers also like to munch on mosquito larvae that tend to share the same ponds and streams. That makes backswimmers a surprisingly valuable ally when it comes to keeping mosquito levels low.

What do backswimmers eat?
Backswimmers are predatory insects that hunt other aquatic invertebrates or terrestrial insects that have accidentally fallen into the water and are often struggling to get out. The biggest backswimmers can take down prey as large as a tadpole or small fish.

Do backswimmers bite or sting?
Backswimmers will bite people to defend themselves, but they typically aren’t looking for a fight. The bite may feel similar to a bee sting.

How do backswimmers get in your pool? Can backswimmers fly?
Backswimmers are able to fly to find new bodies of water to make their home. They do occasionally land in swimming pools by accident and can sometimes survive for a while if the pool isn’t heavily chlorinated. Since there typically isn’t any prey for them in a swimming pool, they will often try to escape to find a more suitable home.


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