Removing Diving Beetles: Best Practices and Tips

We know you’re dealing with beetles invading your space, potentially putting health and property at risk. If you need help identifying and eliminating the infestation at the source, connect with our recommended local professional near you.

If you are looking for ways to get rid of diving beetles that have made your pool or small pond a home, this article will help you remove them.

Seeing black, floating insects in a water body is never a pleasant sight. While it can be anything from diving beetles to Japanese beetles, we’re going to discuss the former here.

Most swimming pools utilize small amounts of insecticides and chlorine to limit the amount of time these insects spend in the pool.

These chemicals either kill the insect or drive them away after their visit.

There is little that can prevent them from entering the pools, but let’s see what steps owners can take.

How to Get Rid of Diving Beetles
Predaceous Diving Beetle

What Are Diving Beetles?

Diving beetles are a type of aquatic beetle found in Europe, Northern Asia, and parts of America.

Growing up to 1.4 inches in length (for the Predaceous diving beetles), these beetles can swim underwater as well as fly large distances.

Known as nature’s scuba divers, these beetles trap atmospheric air under their wings and use it as an air tank to breathe in when underwater.

In natural ponds and fisheries, diving beetles can be a great predator insect that gets rid of small pests, fish, and mosquito larvae.

However, like all beetles, they have sharp, crushing jaws, which are especially prominent on the larvae.

This makes them a potential threat to young kids or pets who might touch the insect and get a bite.

Are They Harmful To Humans?

These leathery black insects can be a scary sight, especially when seen in large groups.

While diving beetles are known as agile predators, humans are not on their prey list!

Do They Bite/Sting?

Diving beetles and their larvae (known as water tigers due to their voracious predator appetite) can bite people using their jaws.

However, there are very few instances of this happening. Most diving adult beetles will first scurry for shelter and then attack a human or pet.

Diving beetle larvae are bolder and may bite first as a defense since they cannot fly.

The bite is painful but does not have any long-lasting effect. The bitten area might suffer from localized swelling, which will go down in a bit.

Boreal Diving Beetle

Are They Poisonous/Venomous?

Diving beetles do inject a toxin on biting.

This helps kill their prey and eventually liquefy their insides so the beetle can suck it out.

However, the amount and strength of this toxin are not enough to cause any harm to humans or even smaller pets like cats and dogs.

While you should treat these beetles with caution and not hold them with your bare hands, it is also not a matter of concern if you end up with a bite.

Why Are Diving Beetles a Nuisance?

Diving beetles grow in still or slow-moving water.

While their predator abilities make them a hit in local ponds and fisheries, backyard swimming pools and indoor water bodies may not be a great place to see them en mass.

Even if you keep your pool clean, diving beetles can fly at night and settle into your pool (as long as it’s outdoors).

Adult diving beetles are attracted to light, and the shine reflected off the water at night – hence it is good practice to have pool covers.

These aquatic insects can also bite people swimming in and around them, offering a nasty shock to the swimmers.

Too many diving beetles in a small pond can limit aquatic life, as we will see next.

Are Diving Beetles Good For Ponds?

This depends on the number of diving beetles and the size of the pond. Too many larvae in a small pond can damage its ecosystem.

The beetles will eat any small fish fry, eggs, and tadpoles.

This can disbalance the overall ecosystem of the pond. The adults will then migrate to another pond, continuing their spread.

In larger ponds with more varied species, there will be larger fish, frogs, salamanders and birds who might keep the diving beetle population in check.

How to Get Rid of Diving Beetles?

There’s no proven method of keeping diving beetles out of your pool forever.

Unless you block every human access to it when the pool is not in use, one simply cannot stop them from flying into a pool at night.

Some preventative measures you can take are:

  • Keep your pool pH between 7.2 and 7.6 to discourage algal growth and make the water unsuitable for fish, larvae, and beetles.
  • Cover your pool when it’s not in use – especially at night. Switch off all lights around your outdoor pool, as beetles are attracted to light and reflections.
  • Diligently clean your pool and remove any leaves and plant matter that falls in. Diving beetles lay eggs on the underside of leaves, whereas Japanese beetles will feed on fallen leaves. Remove any foreign matter as soon as it falls in to avoid contamination.
  • Use a swimming pool algaecide that contains non-ionic ethoxylate. This breaks the surface tension of the water, which allows diving beetles to capture it under their wings. While this will not prevent a beetle from coming in, it will kill existing beetle in a pool which will then drop to the bottom. The dead insects can be vacuumed or netted out.

Call for pest control services now.

Frequently Asked Questions

Are diving beetles harmful?

No, diving beetles aren’t poisonous to humans and pets. So they are not harmful in the traditional sense.
They do have strong jaws and can bite you if needed, but the bite isn’t very dangerous either.
However, they do have a tendency to make small bodies of water as their homes, which means that your swimming pool is a prime target for them.
These beetles can become a huge nuisance in areas where there is lots of water and easy access to small insects.

What eats a diving beetle?

Amphibians, like frogs and fish in the water, love to feast on water beetles.
Since they are found near the shoreline, skunks, raccoons, and other small animals also love to eat them.
Birds also like to eat adults.
As far as their larvae (i.e., the water tigers) are concerned, fish is their most voracious predator.
Lastly, water tigers are considered a delicacy in many places – Japan, China, Mexico, and Thailand.

How long can diving beetles stay underwater?

There is no clear answer to this, but some sources mention that these beetles can stay as long as thirty-six hours underwater!
They have developed a variety of unique adaptations that help them do this, including the ability to breathe underwater (by trapping air under their wings)
They also have legs that have small paddles at the back (which makes it easier to swim).
Lastly, they have compound eyes that allow them to observe everything underwater much better and help them to hunt.

Why are beetles attracted to my pool?

Diving beetles love large bodies of fresh, clean water where they can live and dive as they want to. Your pool fits that description perfectly.
Moreover, if the pool is dirty or has tadpoles and other small insects living in it, then the diving beetles would also have found a nice source of food in the water.
If there are algae and other microorganisms that are living inside the pool, that also can be a reason why they are attracted to your pool.

Wrap Up

Many pools use small amounts of insecticides. However, we suggest that insecticides only be used as a last measure as they harm both humans and insects.

All in all, having a controlled amount of them in aquariums or garden pools can actually be beneficial.

However, it’s best to remove them from any human-used water body, such as pools. Thank you for reading!


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. 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.

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  • 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.

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