Slugs are the common name for shell-less terrestrial gastropod mollusks that are commonly seen in damp & moist places. Among the many slimy creatures seen in our backyard, slugs have the worst reputation because of their primary diet.
The diet of slug includes green leaves of plants making them one of the most painstaking pests to handle. These slimy organisms are mainly found in damp and cool conditions which explain their rapidly increasing population in your backyard after a rain.
Slugs mainly feed on leaves of plants and dead and decayed organic matter with the help of specialized teeth. People often wonder whether these creatures can bite their skin or harm them in any way. We will answer these questions in this article.
So, can slugs really bite? So yeah, slugs can bite. But there haven’t been any reported incidents of a slug bite except for isolated instances. Among the isolated instances that were reported none of them had serious complications.
In this article, we will discuss in detail about slugs, their habitat, and their diet, reproduction, predators, and most importantly about the 27,000 teeth in their mouth. Quite interesting huh? Let’s get going
- Do slugs really have 27,000 teeth?
- Do slugs bite?
- Are slugs poisonous?
- How painful is a slug bite?
- Do slugs bite dogs?
- Can you hold a slug?
- What do slugs eat?
- The digestive system of a Slug
- Is a slug different from a snail?
- Do slugs have any predators?
- How do slugs defend themselves?
- Reproduction in slugs!
- Are slugs endangered?
- The sticky slime of a slug
Do slugs really have 27,000 teeth?
Yes, folks, they do have 27,000 teeth but trust me they can do no harm to you. It’s not that they are some devilish creatures capable of swallowing you in whole with their 27,000 teeth.
Slugs need these many teeth because they don’t chew their food and then swallow. The arrangement of these 27,000 teeth is quite a fascinating evolutionary adaptation seen in them. Instead of an arrangement in rows, they have a ribbon-like flexible band of microscopic teeth known as a radula.
The radula acts like a circular saw capable of cutting through vegetation and eating them. When their existing teeth in the radula wear out, a new row of teeth moves forwards replacing the existing ones.
Do slugs bite?
Don’t be afraid of their slimy look; slugs are harmless creatures. But yeah, there have been some reported instances of accidental slug bite. Trust me; they aren’t going to chase you and bite you down!
In fact, they don’t land a bite intentionally; rather, the poor creature might mistake your body to be a quick snack and try to scrape off their food using their rough tongue (radula), which might feel like a bite to us.
You don’t even need to worry about a slug bite because their teeth are nowhere near to being strong enough to scrape your skin.
Are slugs poisonous?
No slugs aren’t poisonous, and they do not pose any threat to humans. But they can be a real pain for gardeners and farmers. Slugs have a terrible reputation of being one of the most devastating pests because of their affinity towards the leaves of plants.
But then there is a category of slugs known as the Wolf slug, which was once indigenous to Northern Africa. Thanks to the global climatic change and to air travel, these wolf slugs managed to reach Europe and thrive there.
Similar to the other slugs, these guys feed on more or less the same diet and pose no threat to humans. The only difference between the wolf slugs and other slugs is where they lay eggs.
During mating season, while the regular slugs dig a hole on damp ground and lay eggs, the wolf slugs are seen to find a living host. A single bite from these guys can transfer almost a thousand sluglets.
These sluglets then travel through the bloodstream to the gut and feed on whatever the hosts eat. They remain in the stomach for almost two weeks until they hatch and make their way to either the anus or the mouth.
This can prove fatal to smaller mammals and excruciatingly painful for humans. In some cases, the pain is found to persist for almost 48 hours.
How painful is a slug bite?
As discussed in the earlier sections, slug bites aren’t harmful as you would expect it to be. Among the very few reported cases of slug bites, some reported a sense of tingling and pulsation in the bitten area. But there is nothing to be worried about.
In fact, you can’t really call it a bite; instead, it’s the tiny teeth in its radula scraping your finger. Worry not even if a slug bites you; you aren’t going to feel pain.
Do slugs bite dogs?
As I said, slugs aren’t aggressive creatures. In fact, even their method of defense is not offensive. But yeah, there are chances of slugs biting your dogs. If you have a dog, you might have seen how curious & careless dogs can be.
When your doggy is sniffing in your garden or when he is taking a nap on damp soil to escape from the heat, slugs may climb over them and mistake them to be a tasty snack. Even if it bites them, there isn’t any real threat.
But if your doggy shows any allergic reactions, do take him to his vet! You don’t want the sluglets of a wolf slug living inside your doggy, which may prove to be potentially life-threatening.
Can you hold a slug?
Okay, now that’s quite a slimy question. If it were me, I wouldn’t even go near one. But if you want to, you can hold them but make sure you don’t let him crawl over your body.
Make sure that you keep him upside down by its posterior end with its mouth away from your skin. Not because they are poisonous, some people have shown allergic reactions to the mucus of a slug with symptoms ranging from the formation of blisters on the skin to persistent itching.
If you hold a slug and these symptoms start showing up, visit a doctor.
What do slugs eat?
Diet of a slug generally depends on their immediate habitat, availability of food and their species too. Slugs, in general, are omnivorous. In fact, a better suiting description would be a generalist that feeds a plethora of organic matters including leaves of living plants, lichens and mushrooms some slugs are even found to feed on small fruits such as strawberries.
In some regions depending on the availability of food, slugs feed on various flowers such as daisies, lobelia, daffodils, and so on. They also feed on carrots, peas, apples, and cabbages too.
Then there is a group of slugs that feeds on fungi that produce mushrooms. Among the mushrooms, the most favorite for them are the species producing milk-caps and oyster mushrooms.
It is interesting to note that there are some species of slugs that are selective towards the fungi they eat not just the type of fungi but towards the certain parts or developmental stages of the fungi.
The digestive system of a Slug
The digestive system of the family of slugs, in general, is comprised of a mouth, a radula, salivary glands and ducts, an esophagus, a stomach, a rectum, and an anus. The process of digestion starts with the slug scraping food off the leaves, trees, and mushrooms with the help of radula.
Once the food enters the mouth the slug swallows it which then through the esophagus reaches its stomach. The muscles in the esophagus move in a rhythmic way known as peristalsis.
Inside the stomach, food is crushed to break it into smaller parts. It is seen that the slugs swallow sand along with food to easily break down the vitamins and minerals in the food. These vitamins and minerals are absorbed from the stomach itself.
This broken food then reaches the coiled intestine through the anterior portion of the stomach. It is from the intestine water is absorbed from the food leaving behind fecal pellets. These pellets are defecated through the anus that’s situated above its head.
Is a slug different from a snail?
Yeah, a slug is very much different from a snail.
It is quite common to see people calling something a slug if it resembles a snail and lacks the protective shell. But that is not how you differentiate a slug and a snail. Before we proceed any further, you need to be very clear about the fact that both slugs and snails belong to the family of gastropods.
Slugs and snails are the two among the many gastropods and it is interesting to note that some distant cousins of the slugs have developed a sluggy, shell-free shape. This means that there isn’t a separate lineage for slugs.
To make things even complicated some slugs are found to have a hard shell hidden inside their body.
So yeah, slugs and snails are two different creatures yet it isn’t easy to distinguish them.
Do slugs have any predators?
Of course, slugs do have predators. In fact, did you know that biologists almost spent a century to research the predation of slugs? Wondering why?
That’s because some slugs are serious agricultural pests and removing them has high economic value. These researches were fruitful and scientists were able to devise many effective biological control strategies.
Slugs have predators in both the vertebrates and the invertebrates. The predominant predators among the vertebrates include reptiles, birds, mammals, amphibians, & fishes. Among the invertebrates, beetle mainly the rain beetles and some ground beetles that are indigenous to Europe prey on slugs.
How do slugs defend themselves?
Slugs, in general, have a basic method of defense. When threatened or attacked slugs contact their body making them hard and tightly attached to the substrate.
Along with this tight grip, the mucus on their body makes it difficult for the predators to have a tight grip on them. This mucus is obviously not going to taste good deterring the predators from preying on them.
Well, there are some species of slugs that have a more advanced method of defense. For instance, the Kerry slug which when threatened retracts its head & lets go of the substrate, rolls up completely and stays contracted in a ball-like shape. This is quite unique for a slug.
Then there is another class of slugs known as Arionidae which has the ability to self amputate a portion of their tale like a lizard to escape from its predators.
Reproduction in slugs!
Slugs similar to earthworms are hermaphrodites, which means they have both male and female sex organs. But no, they cannot fertilize their own eggs (Reproduce asexually). When a slug has spotted a mate, they encircle each other. The genitalia protrudes from the slugs and the sperms are transferred to the other.
Once the eggs are fertilized, slugs burry a hole in the ground and lay their eggs. A slug can lay almost 30 eggs at a time. On average, a slug can lay 400 to 500 eggs in a year most of which remain under the soil waiting for favorable conditions to hatch.
In the case of banana slugs, something quite fascinating and dorky happens when they mate. Banana slugs show apophallation, which means after a successful mate the male sex organ, gets amputated. The male sex organ gets stuck inside the female genitalia and it is self-amputated or the male organ is chewed off by the other.
Then there is another species of slugs known as the leopard slugs. These guys can only mate when they are dangling on a thread of mucus upside down. Leopard slugs’ penises are actually gigantic and they cannot extend their penis when they are on the ground.
Are slugs endangered?
As discussed in the earlier sections there are quite a few varieties of slugs found on the planet. Not all among them are endangered but yeah some unlucky among them are.
One such type of endangered slugs is the tiny and colorful blue-grey tail dropper. The slugs are unique to the Pacific Northwest and their numbers are found to be dwindling. Another endangered one is the snakeskin hunter slug that was once found widely in South Africa, the population of which has reduced drastically now.
Though these creatures may look slimy and dorky they do have a crucial role to play in our ecosystem. These guys are nature’s cleaning squad responsible for handling the dead and decayed organic matter by breaking them down for faster decomposition.
The sticky slime of a slug
If you have closely observed the slug moving around on solid ground you might have seen the slimy trail they leave behind. If you were wondering why the sole purpose is for easy locomotion.
In fact, this sticky slime is what helping the slug to easily traverse. This slime apart from being sticky acts as lubrication to help the slugs maintain optimum moisture content on their bodies.
Apart from this, the slime provides the slugs’ protection form fungi & bacteria.
The molecular arrangement of the slime has intrigued the scientific community for years. Though the slime may look liquid, it really isn’t liquid rather it is a liquid crystal that flows somewhat like a liquid but has an organized structure at the molecular level.
Another purpose of leaving a sticky slime behind is to find potential mates. Slugs inspect these slimy trails it is more like a mode of communication between them.