Tser's

All About Slugs The gastropod we gawk at, the mollusk behind the movement

slug n. 1. Any of various small, snaillike, chiefly terrestrial gastropod mollusks of the genus Limax and related genera, having a slow-moving elongated body with no shell or only a flat rudimentary shell on or under the skin.

~~ The American Heritage Dictionary Webster's Encyclopedic Unabridged Dictionary of the English Language adds:

"feeding on plants and a pest of leafy garden crops"

I've always been fascinated with slugs. Well, that's not entirely true. When I was two years old, my family was camping in the Coast Range, which we did all the time. I was playing on a log near the campsite when I started screaming bloody murder and scared the heck out of my mom, who thought I had encountered a bear (black bears were still common around there), when really I had spotted a large banana slug sliming its way along the decaying wood. That was the only time I ever feared slugs.

Love of slugs is often considered odd. Frankly, though, slugs are fascinating. The most common slug around here and where I go camping is the banana slug. They are aptly named, long, olive green creatures. Some of them are more yellow or more green, and some sport varying amounts of black spots. They can grow to be very large. The CyberSlugs are based on this species.

We have various garden slugs that live in Oregon as well. There are black ones, bright orange ones, speckly spotty ones and drab brown ones. I'm not an expert on the various species, though it interests me.

This diagram illustrates the different parts of a slug.

First make sure you rinse your hands, but don't dry them. I'm not sure how much truth is in the tales, but since salt hurts slugs and your hands are salty, touching a slug may hurt it. Washing your hands first should eliminate this threat, since even though it doesn't get all the salt off, the water and the slug's slime will probably protect it.

That's probably the first thing you'll notice about the slug. If you pet it along it's keel (usually that looks like a small line along its back), the slime will feel slippery. The slime comes off your fingers fairly easily unless you are disturbing the slug (such as being rough with it). You can use a leaf to get it off. This slime that the slug normally secretes is actually used to make sure things don't stick to it. After all, if you were damp and crawled around in the dirt all day, pretty soon you'd be caked in leaves and dirt and mud. The slimey trail the slug leaves behind also leaves behind all the dirt and gunk.

When slugs are disturbed or injured, the slug slime becomes more sticky. That's why when you step on one early dawn barefoot the stuff sticks on for a very long time. I don't condone going around stepping on slugs or any other kind of animal cruelty. In fact, I abhor it.

One fascinating thing about this slime is that even though its fairly slippery, which you will notice petting or (if you're like me) picking the slug up and letting it crawl along your hands, is that they can use it to hold on to sheer surfaces like glass.

Another fascinating thing about the slime is its a natural anaesthetic. If you lick a slug enough, your tongue will go numb. In fact, some Native Americans used to put slugs in their mouths when they had a toothache and let it crawl around. I don't recommend licking a slug, because I'm sure it's not good for them.

One of the most interesting aspects of petting a slug is touching the optical tentacles (also called eyestalks). If you gently poke them, the slug will pull its 'antlers' in, hiding. If you are patient, the slug will slowly come out and continue on its way. If you continue to gently touch it, eventually, it stops hiding from you and continues on its sluggish way. Slugs don't see very well, mostly just light and dark, so they can see if a shadow passes over them. To find food, they taste and poke about with their sensory tentacles which they can also retract under the mantle.

One of the most frequently asked questions about slugs is what the hole in its side is. The hole, located on the mantle on the right side of the slug, is the slug's pneumostome. This is like the slug's nose, and is the hole it breathes out of. The slug has the ability to close this hole.

Slugs are hermaphroditic, meaning they have both male and female reproductive systems. The genitalia are covered by the mantle.

The slug's foot is a very strong muscle. The slug moves by rippling the muscles in it's foot and skirt and sort of sliding along the ground.

The mouth is located on the bottom of the slug. The slug crawls over it's food to eat. Slugs eat various leafy plants. A few favorite foods are cucumber and oxylis. Oxylis is a common plant in the Northwest, growing in fields. It has three leaves and basically looks like a large, light-green clover. During March, it's often sold as a shamrock for St. Patrick's day. Oxalis is edible to humans, too, and tastes like green apple candy. Do not eat plants you are not sure are nontoxic. I will try to find a picture of oxylis or scan it for this page. Slugs eat many other plants as well, as many gardeners are sure to know. If you place a slug on glass and look at it from beneath, you can see its rippling muscles as it moves and also it's rasping tongue, which it uses to scrape up and nibble on food.

This was an attempt I made at drawing a more realistic, garden-type slug on my computer, using Paint Shop Pro 3.12. It didn't come out perfect, but shading is hard with a mouse. Anyway, this drawing gives more detail of the optical tentacle and sensory tentacle setup, as well as the appearance of the keel and skirt.

Slug Adventures

When I was younger, I used to gather all the banana slugs I could find in coolwhip containers (sans coolwhip) with small holes poked in the lid while I was camping, and my sister would do the same. At first, I used sticks and leaves to gently lift the slugs, but as time went on I realized they weren't going to hurt me, and just picked them up with my hands. We'd pick the handsomest, quickest, largest, smallest, or spottiest slugs from the bunch, and write numbers on construction paper, which we cut out with scissors. We'd place the tiny pieces of paper on the slug's backs (they pretty much stuck by themselves) and lined the slugs up on a pre-set racetrack. Sometimes we then left; it depended on how long the track was and if we wanted to wait long enough for one of the slugs to win. If we left, we'd come back later and see if one of the slugs had won the race yet. Sometimes they'd lose their numbers, other times they'd still be wearing them.

We often named the slugs. I remember one of my favorite slugs was a pure olive-green beauty of medium sized with one big black spot right in the center of his mantle named Oscar. My favorite slug was Trigger, though, an absolutely huge, race winning, plainly colored slug. Number One in red construction paper.

I decided to keep Trigger, so I set him up in a coolwhip container that I cut holes in the top with a hole punch. Trigger was about the size of the large slug in the labeled diagram at the top of the page. I set him up with dirt, gravel, oxylis, carrots and all sorts of sluggy amenities, where I would keep him until we returned home from camping and I could set him up in a better habitat.

He escaped.

Trigger, the size of the slug in the diagram, squidged through the hole-punch sized air hole. My parents didn't believe me. Frankly, I didn't believe he had escaped through it. I figured someone had let him go (my parents hated how I brought home all manner of critters from camping). However, I searched diligently (I loved that slug) and found him squooshed up under the stool I had set the bowl on. I felt I was truly blessed to have found him.

I put him back in his bowl, using a paper towel stretched over the bowl between the bowl and lid to cover the holes without blocking the air. Trigger came home with me without another incident, and I still thought maybe the lid had gotten left off.

However, one night very soon after we came home, the paper towel (which I had been replacing often) had gotten damp and sort of disinigrated, and Trigger once again was on the loose. I searched for him for hours, extremely upset, because I knew that in the warm, dry house, Trigger would dry out and die. My mom, though she loves animals, even slugs, was understandably disgusted that a slug was sliming around her house. I found him the next day on the other side of the house near the backdoor, a bit dry, but okay.

If you've seen the CyberSlugs, you'll see that available for adoption are Racing Slugs. Those Slugs are based on my childhood adventures with the banana slugs while camping. Also, if you visit my own CyberSlugs, on this page, you'll notice that my own Racing Slug, with a red racing blanket, Number One, is named Trigger after my infamous childhood pet banana slug. The CyberSlugs were developed in his treasured memory.

This is a picture I did in PSP using a mouse of a realistic slug. It's the species Limax maximus, which has a maximum length of four inches.

Another Mollusk-Keeping Adventure

Once I found a snail when I was hiking at camping. It was a light colored, tannish yellow thing (much like the CyberSnails offered for adoption), so I decided to take it home. Imagine my surprise when a mere days later, she started digging holes with her "tail" and laying eggs all around the edge of the large canning jar I had her in (really, snails are hermaphroditic like slugs, but I'll call it a female because it's easier). What was really neat was that she laid most of them up near the glass, so I could watch the eggs develop.

She dug many holes and laid large clutches of eggs in each one. I watched as baby snails formed inside the tiny, translucent eggs, and even got to watch many of them hatch. The baby snails slimed their way to the surface. They were tiny, smaller than a cucumber seed, and see through. There were more than a hundred babies (which was a lot for the canning jar, but I didn't dare move them once she started laying the eggs). They ate a lot of cucumber, and grew fairly quickly. After watching them for a while from the time the eggs were laid and hatched, I let all the babies go near where I had found the mother/father. That was a very memorable snail-keeping experience.

The truth is, any two slugs or snails can mate, though in captivity it's not as likely to happen as in the wild, since the conditions are not usually as natural. What's even more bizarre is if there are no other slugs, the slug can mate with itself and produce offspring, though this rarely happens. If you ever find yourself with galloping gastropod babies, I'd suggest you watch them for a while and let them go in the wild. Slugs and snails have so many babies because of the high fatality rate for the young.

Slug Hunts

Many things eat slugs. Many birds, fish, and small mammals would love a slimey slug feast. They are one of the favorite foods of garter snakes.

One of their main enemies is humans. Humans everywhere search for ways to destroy or remove slugs from their gardens, since they are quite a pest and chew holes in garden crops. This is not the place to find slug killing methods, as I am a slug and snail lover, even though they've absolutely destroyed my hostas and get to much of my lettuce before I can harvest it.

One thing I implore you not to do is pour salt on them. This is very cruel to the slug, since the salt causes the slug to suddenly dehydrate by sucking all the moisture out of them, and slugs are mostly water.

There are other ways used to destroy slugs. One often touted manner is beer and slug hotels. However, some slugs seem to just drink to beer and slime away, though some will crawl in and drown. Some collect slugs and use them as bait for fishing. Others use slugs as garter snake food (supposedly, black slugs should not be fed to garter snakes). Many garden centers sell slug bait. Be careful using such things around pets -- check to see if they are safe around cats, dogs and birds.

A very safe method of slug control is using an old, wide board. Lay it where the slugs are bothering your garden, and in the morning, slugs will have gathered under it to escape the day's rays. Then you can relocate the slugs to somewhere where it won't bother any gardens, like a nearby forest. Some people would rather step hard on the board and squoosh the slugs underneath. This will attract more slugs the next night that will munch on the dead ones. Poor slugs!

I understand that many people are extremely frustrated by slugs in their gardens. Although I love to grow vegetables (I grow fresh veggies to share among myself and pets every year), I'm biased in favor of the slugs, which are native creatures which have just as much right to be here as me. I try to work around the slugs.

There are several methods of natural, gentle slug discouragement. There are some plants which slugs avoid, which can be planted at the edge of the garden.

My favorite way to keep slugs under control in the garden is copper! Copper is uncomfortable for slugs and they don't like to crawl over it. You can purchase copper tape at the garden store, and place it around the edge of a raised bed or pots. As long as no weeds or plants create a "bridge" over the tape, slugs will have a hard time crossing it. Copper mesh as a fence will serve a similar purpose.

Gastropets

If you are interested in pet slugs, I have a page dedicated to Keeping Slugs and Snails.