Maggots in dog poop: why it happens and how to stop it

Why flies pick dog poop

Adult flies look for somewhere moist and rich in nutrients to lay eggs. Dog droppings fit. NC State Extension notes that blow flies feed on animal waste and can "rapidly lay hundreds of eggs on dog droppings."

The eggs look like tiny grains of rice. Within a day they hatch into small cream-colored larvae, which is what you see wriggling in the pile. Those are maggots, and they are not a sign that your dog is sick. They are a sign that the poop sat long enough for a fly to find it.

How fast maggots show up

The timeline below comes from NC State Extension's blow fly guide. The exact days shift a little by species, so read it as a rough clock, not a stopwatch.

A pile that sits for two days can already hold maggots. A pile that sits for a week can finish the cycle and send a new batch of adult flies back into your yard.

Maggots in fresh poop, straight from the dog

Sometimes you see maggots in a dropping that is only minutes old. The Merck Veterinary Manual calls this pseudomyiasis: the dog swallowed fly larvae, and they passed through the gut and came out in the stool.

Per Merck, this happens when a dog grooms larvae off a wound or its coat, or eats carrion (a dead animal) that already has maggots in it. The manual also notes that stool that was not fresh can have larvae in it already, because flies laid eggs before you got there.

If you keep finding maggots in fresh stool, mention it to your vet. This page is general information, and a vet should look at a sick dog.

What to do about maggots in the yard

Pick the waste up, maggots and all, and seal it in a closed bag before it goes in the trash. NC State's advice is to remove pet waste from the yard as soon as possible and throw it away in a closed bag.

Then deal with the bin. NC State suggests rinsing garbage bins with bleach to kill leftover eggs, larvae and pupae, and keeping the lid shut so flies cannot get in.

Check the rest of the yard for other breeding spots. NC State says blow flies also feed on garbage and rotting food, which is why you see them around trash cans, so a bin with a loose lid can keep the fly problem going even after the poop is gone. Then look at the spot where the pile sat. If the lawn is stained or the smell lingers, our page on yard deodorizing and sanitizing covers what that service involves.

How to keep flies from coming back

The only thing that works long term is a shorter gap between a dog pooping and someone picking it up. Flies need time, and the eggs need about a day to hatch. After the larvae finish feeding, they pupate and emerge as adults about 8 days later, per NC State, and those adults can lay hundreds of eggs of their own. One neglected pile can start the next round for the whole yard. If you scoop every day or two, the pile never grows a crop.

Most people skip days, especially in summer when it is hot out. That is where a schedule helps. Our weekly service is $89 a month, and twice-weekly is $149 a month for yards where a week is too long. Both have no contract, and the first cleanup is free.

A weekly visit leaves piles sitting up to seven days, which is longer than the egg-to-maggot clock above. For a yard with more than one dog, twice a week shortens that gap. Our guide on how often to pick up dog poop covers the schedule question.

When to call a vet

Call your vet if you see maggots on your dog's skin or coat, around a wound, or around the rear end, or if the dog is eating dead animals and passing larvae. These are not yard problems, and they need a professional.

Also call if diarrhea or other changes come along with it. We do not diagnose anything here. This page covers the yard side, and your vet handles the dog.

Questions people ask