It’s a Slug Life: Fun Facts About Slugs


Some creatures are really interesting to look at. You see them, but you don’t REALLY notice them.  Occasionally, you just have to stop, bend down and take a closer look. Slugs are one of those creatures.  But what are they good for?  We’re going to explore the life of a slug and find out.

In a world where we all want things fast like bikes and video games and even our food, this little creature crawls along barely moving. Large slugs like the banana slug travel at 6.5 inches per minute, so it takes almost 7 days for a slug to travel a mile.  That means a slug would take 237 days to travel from Fayetteville to Bella Vista. 

What is a slug?

Slugs have no skeletons, and crawl around on what looks like one big huge foot, and they only have one lung. Slugs are gastropods, distantly related to mollusks like squids, mussels, snails and oysters. There are more than 40,000 gastropod species.

Where do slugs come from?

Slugs were introduced from France, where they were apparently used for food. EEWWIE YUCKERS!  

Don’t eat slugs, even on a dare.  They have parasites that can hurt you.  And wash your hands with lots of soap if you touch them.

Slugs have meandered their way all over the United states, but generally hang out where there is plenty of moisture. One scientist started a website to track the distribution of the native land slugs of North America. Data is still being collected by a small group of people. 

How are they born?

Slugs come from eggs.  Some slugs lay up to 500 eggs per year, which mature in three to six months and then they start laying eggs themselves. Slugs generally live 1-5 years.

Where do they live?

While snails have shells to help protect their skin from drying out, slugs must find other ways to retain their moisture. In dry conditions, slugs insulate themselves in dirt and leaves until their environment becomes moist again, typically venturing out to eat at night.  They live under yard debris and that’s perfect for what they are great at.  Helping with decomposition.

What’s the difference between slugs and snails?

Snail and slug aren’t scientific terms.  Snail is used to describe a gastropod with a shell. Slug is used to describe a gastropod without a shell. There is little difference between them except the shell, and slugs evolved from snails losing all or part of their shell over time.

How are they beneficial?

  1. Slugs play an important role in nature, breaking down decaying matter and recycling it back into the soil. Overall, slugs are scavengers. They eat substrate, or decaying organic matter that includes dead and rotting plants, leaf litter, fallen fruit, fungus, old wood animal droppings, toadstools and compost. Occasionally you might see them nibbling on a leaf, but it is probably already damaged or diseased. 
  2. Slugs can be predators by eating snails, worms, maggots and other insect larvae that are harmful to garden and flower bed plants.
  3. Slugs are part of the great circle of life as many different animals feed on slugs. Some common predators are snakes, raccoons, opossums, hedgehogs, beetles, ducks and various other birds.
  4. Slugs don’t have a shell for protection like a snail, but they make up for this disadvantage by being able to fit their smooth, flexible and lubricated bodies down into the tiniest crevices. This makes them truly subterranean creatures.
  5. Slugs are great to observe close up because it takes so long for them to get away.  Next time you see one, take a look at the telescopic eye and feeler stalks on the head; peer into the large breathing hole on the right side of the body (like snails, slugs are not bilaterally symmetrical); and admire the rhythmic muscular ripples on its belly and the big huge foot as a large, moist slug glides smoothly and effortlessly on its path.

Slug vocabulary:

Bilaterally symmetrical – the body is divided into equal right and left halves.

Debris – the remains of something broken down or destroyed.

Decomposition – to break down or be broken down into simpler parts or substances especially by the action of living things (as bacteria and fungi) Leaves decomposed on the forest floor.

Evolved – to develop gradually; come into being.

Gastropods – snails, slugs, conchs, and many other similar animals with or without shells are all called gastropods by scientists. The word gastropod comes from Greek and means “stomach foot,” a name that owes its existence to the unusual anatomy of snails.

Substrate – the surface where an organism grows.

Subterranean – secret or hidden, as if underground.


By Renee Durham