What Eats Water Scorpions? Uncovering Their Natural Predators

Water scorpions are fascinating creatures that inhabit fresh and stagnant water bodies. As a predator in the aquatic world, they might appear invincible, but nature always finds a way to maintain balance. In this article, you’ll get to know the natural predators of water scorpions and their role in the ecosystem.

These intriguing insects, despite their strong resemblance to terrestrial scorpions, are part of the Hemiptera order. Just like other insects, water scorpions are not without their enemies. Their predators are fundamental in keeping the water scorpion population in check, ensuring that the aquatic ecosystems they inhabit remain balanced and healthy.

Some predators that feast on water scorpions may come as quite a surprise. Familiar creatures such as birds, frogs, and even some large aquatic insects all play a role in the food chain, preying on these unique insects. Read on to find out more about these predators and how they interact with water scorpions in their habitats.

What Are Water Scorpions?

Physical Characteristics

Water scorpions are a fascinating type of insect belonging to the family Nepidae, not to be confused with arachnids such as true scorpions. They have slender, brown bodies, measuring around 30-35 mm in length, with a sharp needle-like appendage at the tip of their abdomen. These insects possess three pairs of jointed legs, with their front two legs modified for grasping prey.

Habitat and Distribution

As their name suggests, water scorpions reside in aquatic environments. They are commonly found in a variety of water habitats such as mud, streams, and ponds across Europe and North America. Brown Water Scorpions (Ranatra fusca) are one example of a species found in both ponds and streams.

Behaviour and Adaptations

Water scorpions are nocturnal hunters, using a unique “ambush” strategy to capture their prey. Their coloration helps them blend in with the surroundings, making them nearly invisible to their prey. Additionally, they have a siphon system that functions like a snorkel, allowing them to breathe as they lay submerged in water to avoid detection.

  • Hunting method: Ambush
  • Movement: Swim or crawl
  • Breathing: Siphon system

Species and Genera

Water scorpions belong to the family Nepidae, which includes over 270 species worldwide. Among these, there are more than 10 species in North America belonging to the genus Ranatra, sometimes referred to as water stick insects. Knowing the diversity within this fascinating family can help you gain a greater understanding and appreciation for these remarkable insects.

So now that you know more about water scorpions, their physical characteristics, habitats, behavior, and species diversity, you’re better prepared to explore their intriguing world. As always, remember to tread lightly and be respectful of the environments where these unique creatures make their home.

What Eats Water Scorpions

Amphibians and Reptiles

Frogs, snakes, and lizards are common predators of water scorpions. For example, in regions like Texas, California, and Arizona, various species of frogs and geckos might feed on these aquatic insects.

Water scorpions are not easily spotted by their predators because they have physical characteristics for camouflage, such as their sharp and slender shape and similar color to their habitats.


Birds like eastern screech owls, elf owls, and great horned owls are known to prey on various bugs, including water scorpions. In South Africa, the southern ground hornbill is another bird species that might feed on water scorpions.


Mammals such as bats and rodents are also known to eat water scorpions. For instance, shrews and grasshopper mice (including northern and southern grasshopper mice) might consume these insects. Meerkats and mongooses could also include water scorpions in their diet.


Invertebrates like spiders, tarantulas, and the Amazonian giant centipede are known predators of water scorpions. These aquatic invertebrates rely on their physical characteristics and habitats to avoid being detected by their predators.

Physical Characteristics

Water scorpions have physical traits that help them blend into their surroundings:

  • Length: Averages from 0.8 to 2 inches (2 to 5 cm)
  • Sharp, slender body shape
  • Coloration: usually brownish or olive-green

Habitat and Distribution

Water scorpions are found in various water habitats like:

  • Mud
  • Streams
  • Ponds

They are commonly found across the United States (Texas, California, Arizona) to South Africa but are not found in Antarctica.

Behaviour and Adaptations

As nocturnal creatures, water scorpions are difficult to detect in their natural habitats. They can swim and crawl underwater, using their snorkel-like appendages for breathing. Their ambush strategy allows them to capture their prey while avoiding predators.


In summary, water scorpions are interesting aquatic creatures that play a role in the ecosystem by acting as both predators and prey. You might be surprised to learn that several different aquatic species feed on water scorpions, helping to keep their population in balance.

For example, larger predatory insects like Giant water bugs can consume water scorpions. Additionally, fish are also known to prey on them, further exemplifying the natural food chain process in aquatic habitats.

It’s essential to understand that water scorpions themselves are predators as well, feeding on small aquatic insects using their mantis-like forelegs to capture their prey. This demonstrates that they play a crucial role in maintaining a balanced and diverse ecosystem.

We hope this article provided you with a greater understanding of the diet and ecological role of water scorpions. By appreciating their importance in the natural world, you can further develop your knowledge of the complex aquatic ecosystems they inhabit.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Water Scorpion from Australia


Aquatic Mantid Like Creature from Australia
Hi guys,
congratulations on the new site. I came across this guy on the edge of a dam at my property. At first I thought it was just a leaf sticking out of the water but then noticed the eyes. I have never seen anything like it. Any ideas Queensland, Australia

Water Scorpion from Australia
Water Scorpion from Australia

Hi Aussietrev,
What a crazy looking photo of a Water Scorpion.  We believe it is in the genus Nepa.  Water Scorpions are related to Giant Water Bugs, also known as Toe-Biters.  The stinger-like appendage is actually a breathing tube.  We hope you have checked out our new site feature, What’s That Bug Down Under? that features our many Australian submissions.

Letter 2 – Water Scorpion from Australia


Giant Water Bug
Location: Queensland, Australia
January 26, 2012 12:50 am
Hi guys,
Hope you like these shots of a giant water bug that was hanging around banging into a shiny piece of stainless steel in my carport. They will often mistake a reflective surface for water and attempt to drop into it.
The bug played dead when I got close to it and it allowed me to turn it over for a shot of its piercing mouthparts. It was determined not to give itself away until I picked it up and took it over to some long grass. When I dropped it on the grass it quickly righted itself and flew away.
Signature: aussietrev

Water Scorpion

Hi Trevor,
The very flattened body and extremely long, posterior breathing tube indicates that this is a Water Scorpion, and not a closely related Giant Water Bug.  Interestingly, we found a photos of a Water Scorpion from Australia submitted by you in 2008 in our archive.  We decided to do a bit more research and we found the AusEmade website that has a photo of an Australian Water Scorpion from Simpsons Gap that is identified as
Laccotrephes tristis and contains this information:  “One of the interesting looking insects found swimming in the pools is the Water Scorpion, whose other common name is Toe-biter. These strange looking creatures are carnivores, feeding on other aquatic organisms that they can capture including tadpoles, small frogs and small fish. They swim with the tip of their long needle like tail breaking the water surface, acting as a breathing siphon.  With their large pincer-like forelegs used for seizing their prey, Water Scorpions can inflict a nasty nip, although they are also known to play dead when disturbed. Once they have grasped their prey, they inject a venom that liquefy the prey from the inside, which enables the Water Scorpion to suck out the prey’s body fluid.”  The Identification and Ecology of Australian Freshwater Invertebrates website also has some good information.  The Atlas of Living Australiahas a distribution map.

Water Scorpion

If you look closely at your close-up photos, you can see tiny red spots which we suspect are Mites.  Several sources indicate a common name of Toe-Biter which is shared with the North American Giant Water Bugs.

Water Scorpion


Letter 3 – Water Scorpion eats Damselfly


weird water bug
Hi Bugman,
I love your site! I took this photo last July 15 in southeast Michigan. I was trying to get a shot of those damselflies when I noticed that weird thing under the lily pad that appeared to be eating one of them. It was in a small man-made pond at a botanical garden. I’m not even sure where to look for it in your archives, so I’m going straight to you. Any idea what it is?
Martha H.
Ann Arbor, M

hi Martha,
Wow, what an awesome image of a Water Scorpion in the genus Ranatra eating a Damselfly while other Damselflies sit unaware. Interestingly, this is the third photo of a Water Scorpion submitted to our site today.

Letter 4 – Water Scorpion from Costa Rica


Subject: Identify this insect
Location: Gunacaste. Costa Rica
February 16, 2016 2:43 pm
I found 2 of these in a pool in Costa Rica
Signature: Gary C

Water Scorpion
Water Scorpion

Dear Gary,
Because of its reported painful bite, the aquatic, predator you discovered is known as a Water Scorpion.  Water Scorpions stalk prey by crawling through aquatic plants, and adults are capable of flying, meaning they can seek a new pond if one dries out.

Thank you
I will let the locals know as they had no idea when the guy picked it up it stung him with the tail.
Gary c

Water Scorpions do NOT sting.  They bite with a piercing mouth designed to suck fluids from the body of prey.  What you have mistaken for a stinger is actually a breathing tube that acts kind of like a snorkel.

Letter 5 – Water Scorpion from Australia


Subject:  Possibly a Giant waterbug
Geographic location of the bug:  Tom Price Western Australia
Date: 04/19/2018
Time: 03:52 AM EDT
Your letter to the bugman:  Hi me and my daughter found an interesting bug in our pool. We live in Tom Price Western Australia (the Pilbara region) we found It  swimming around in the pool, when it was brought out it made the shape of a leaf. I suspect it is a Giant water bug, but this one is quite thin and it has long “tail”possibly a syphon for air while it lays in wait in the water.
Ive never come across one that looks like this before
How you want your letter signed:  Jordan Chennell-Kuehne

Water Scorpion

Dear Jordan,
We reserve the name Giant Water Bug for the group of aquatic predators in the family Belostomatidae.  This is actually a Water Scorpion, another aquatic predator from the family Nepidae, and both families are classified together in the superfamily Nepoidea, meaning they share physical similarities.  According to Ausemade:  “With their large pincer-like forelegs used for seizing their prey, Water Scorpions can inflict a nasty nip, although they are also known to play dead when disturbed.” 

Water Scorpion
Thank you so much for this information, Ive already got all the details for my daughter she loves insects and is very interested so of course we encourage studying them and learning about them.
Thanks again


Letter 6 – Water Scorpion from Cameroon


Subject:  Please let me know more about this object
Geographic location of the bug:  Limbe, Cameroon, Africa
Date: 03/23/2019
Time: 05:51 PM EDT
Your letter to the bugman:  Hello,
Been seeing these strange insects around the house recently so wanted learn about them more ( not too long ago I even saw 2 brahminy snakes).
For more precision about the insect on the picture, at a certain point it was able to mimic a small piece of wood by straightening his whole body like an | (All legs behind and stiking to the body with his 2 things?? in front perfectly straightened forward).
Well thanks for your time and patience.
How you want your letter signed:  Sally

Water Scorpion

Dear Sally,
This is a predatory Water Scorpion, an aquatic True Bug that is capable of flying from pond to pond.  Handle Water Scorpions with caution as they can deliver a painful bite.


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

4 thoughts on “What Eats Water Scorpions? Uncovering Their Natural Predators”

  1. Thanks for the correction on the ID guys, too much Australia Day celebrating. Yes it had several mites on the underside. I don’t think I’d like to be stabbed by that hypodermic they have for a mouth either.

  2. The mites are probably parasitic larvae in the water-mite family Hydrachnidae, genus Hydrachna. Species in this genus are unusual for water-mites in that the larvae parasitize aquatic Hemiptera.

  3. This page has been very helpful, just found one of these in my middle dam and wanted to find out what it was, thanks for sharing!


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