“We started seeing an infestation of dead worms/worm-like creatures around the edge of part of the pool,” reports this reader in a small town outside Sacramento, California. The worms in question appear to have segmented, yellowish bodies, and have small legs protruding from one end of their bodies.

“We recently had our pool resurfaced,” starts our reader in her story. The dead worms were found in her pool a week after this was done. “My husband noticed that the [concentration of] worms tends to be most heavy in the widest spacing between the pool coping and the concrete walk around the pool.”

Then, a few days later, our reader and her husband noticed an infestation of the same worms on their concrete front porch. The creatures were “working their way into our entry inside the house.” The following day, they took notice of “about 30” worms in their den. They were on the concrete floor and “dropping onto the couch.” While the worms have “predominantly” been found on the ground, they have also seen a few crawling up walls.

Our reader provides an apt description of the creatures: “The worm-like creatures look almost translucent, with dark spots on the head/tail area. They also have a light cream-like color with some brown. They look like a worm, crawling about and sometimes curling into a “C” position. Upon closer inspection, they have six legs, toward what I am assuming is the head. When they dry out/die they turn a brown color.”

Now, given the physical characteristics of these worms, we would suggest that they are either mealworms or wireworms. Both come from different families of beetles, the mealworm being the larva of a darkling beetle, while the wireworm being the larva of a click beetle. They are very similar, physically speaking: they have near-identical coloration, three sets of legs near their head, and they are generally the same size (though wireworms can grow bigger). Their differences lie mostly in what they feed on.

Mealworms are scavengers, meaning they eat things that are left behind by others. Such things include grains, decaying plants, and dead animals. On the other hand, wireworms will eat a variety of things, depending on the species of click beetle they come from. Certain species of wireworms eat plant stems and seedlings (these ones tend to stay underground), while others are predatory, and will hunt other insects in wood.

In either case, neither species has reason to jump in our reader’s pool, or to be attracted to concrete or couches. This would only make sense if there was bountiful food for them in any of these areas, though we doubt it. We think it more likely that the adult beetles are simply laying eggs near these areas and they are all hatching at the same time. After all, both families of beetles can lay up to hundreds of eggs at a time, which would explain why our reader found so many larvae at once.

That said, it is still odd that larvae have been found in different spots. Perhaps the wind has blown certain sacs in different directions, or maybe our reader, her husband, or a potential pet, has accidentally brought eggs with them into the home. We do not know the answer to this question, nor do we know why so many of the larvae would end up in the pool. Maybe some of the eggs were deposited on the inside of the pool cover, assuming our reader has one. This too is a mystery.

Speaking of pool covers, if our reader does not have one, getting one might be a good idea, as this can help prevent worms and other creatures from entering her home. Likewise, she should make sure that all of her window screens are intact in her home, as well as that there is not too much debris (leaves, twigs, and rocks, for example) leaning up against the side of her home, as they can attract creatures.

Lastly, we should note that neither mealworms nor wireworms are directly harmful to humans, though mealworms are pests and can cause a lot of damage to the grains and plants in one’s home. So, as irritating as it is to have so many worms crawling about the place, we do not recommend that our reader eliminate them, unless the infestation gets out of hand. In that case, she might want to call an exterminator. The best she can do is apply the preventative measures mentioned earlier, as well as move any larvae away from her home.

To conclude, the worms our reader and her husband have been finding in their pool, as well as in and around their home are either mealworms or wireworms: we are not sure. Although we were not able to provide concrete answers or surefire solutions to this infestation, we hope that this article nonetheless proves useful to our reader and her husband. We wish them the very best.

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