Backswimmer Insects Drag Prey Into the Upside Down | Deep Look

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.

DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

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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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[featherance]

The ability of flipping up from underwater and take off just impressive.
Learnt about them swimming upside down under water but never thought they could fly!

[NerdyJackalope]

This bug is literally a traveler between two worlds. I love it!

[sunxiiro]

Me: Oh they’re cool

“One of their favourite snacks are these mosquito larvae”

Me: OH THEY’RE AWESOME

[reionj]

We need more of them yes, especially when it comes to mosquito larvae. They are cool and scary how they drag their prey to a watery grave. 😬 😵Imagine having a predator like that to deal with eeeh

[yeeturmcbeetur]

Me: wow. That thing is terrifying.

“It’s favorite snack are mosquito larvae”

Me: “wow. I love this bug”

[turkeyking]

I can’t believe these videos are free to watch! They’re amazing!

[diamondwolf]

I’m always dumbfounded at the absolutely amazing macro shots you guys get of creatures. Super cool!! A couple years ago we found a backswimmer in our pool, I was excited to see a feature on a bug I’ve always been curious about! Thanks for the work you do, Deep Peeps :)

[dana-kahil]

I am happy to say that I have never in my entire life seen this insect. So many wonders yet to discover and get to know.

[claudylings]

GOODNESS, just when you think you've seen everything. I had no idea that something like this was even possible. Mind blown I am

[KPdroflxp]

The "leathery cover" are the front wings which are also used while flying. They are also called waterbees in German because of their painful bite.

[WakleeKins]

Its been a year ago since I started a backswimmer farm and they truly are fascinating creatures, they are almost alien like, smart yet scary, they will not hesitate to bite something 100x their size if they feel threatened. Thank you for this video seeing them upclose like this is truly amazing

[reionj]

Awww they really are like little row boats, I didn't even know they had wings, mind was blown 😳. Love these videos ahh❤

[orawal]

that shot at 1:28 is pure hollywood the terror rising from the back

[balloonga]

Learning about insects I have never heard before is always fascinating.
Thanks Deep Look for introducing backswimmers!

[TheMightyX]

I love that you called them “bugs, ” because that term is so often misapplied, but in this case, it’s 100% correct!

[GoTommyBoy]

They kill mosquitoes? They're alright in my book.

[blackberry]

This channel has no idea how much it makes my day whenever they upload.

[maddiewaters]

I had no idea they could fly! Amazing creatures

[juanjose]

These have been one of my favourite insects since I was little, I used to explore a couple ruins of houses near mine that had lots of terrains and abandoned swimmingpools that went through the natural cycle of the seasons as if natural ponds, and I could watch this guys for hours, once I saw one trying to catch a newborn Podarcis vaucheri, but it proved too much and got away. Great video as always.

[Randomdude]

“You don’t seem to understand, my pool isn’t yours conquer..”