There are three different kinds of snails: those that live in freshwater such
as lakes and ponds called freshwater snails, sea snails that live in the sea and
land snails which is what we are concerned with here. You will learn about the
different parts of a snail’s body, how land snails move, what they like to eat and
what makes them happy or sad. I will also present a few ideas for experiments
that might help you to understand more about these fascinating snails.
Sixty-Six Slithering Snippets
- Snails are shellfish. They belong to a group called MOLLUSCS.
- The snail has a shell to protect itself from danger.
- If a snail is disturbed, it will disappear inside its shell and stay there until it feels safe to come out again. To defend itself, a snail can emit a FROTHY SUBSTANCE which will repel predators such as birds or chickens and hence stop an attack.
- When a tree has been chopped down, rings inside it tell us how old the tree is. When a snail grows, it was once thought that it could grow a new spiral on its shell every year, just like the ring of a tree. These rings are called WHORLS (sounds like ‘walls’) but are now not thought to demonstrate annual growth.
- A snail has a soft body that is long and slimy. The shell that protects it sits upon its back. Unlike in fairy tales, snails cannot lose the ‘house’ on their back because both body and shell are connected by membranes. It is very unlikely that the two would ever become separated unless a bird or chicken is able to pull the body out using their beaks.
- Land snails have many different kinds of coloured shells. An Apple Snail for example has a yellow shell and an African land snail has different bands of brown, pink and cream. Some snails have very pretty shells.
- The bottom of a snail’s body is called a FOOT.
- Inside the FOOT are lots of muscles, just like we have muscles in our bodies. When the muscles work – or contract – the FOOT moves and the snail is able to move around. Sometimes this FOOT is known as a CREEPING FOOT because of the movement of the muscles.
- In the FOOT there is something called a GLAND that makes SLIME, a sticky substance that helps the snail to move along.
- Land snails can walk up stalks, sticks and walls without getting hurt, all because they are protected by the production of SLIME.
- If you watch a snail climbing up a sharp edge, you will see that it can curl its body around the edge, not actually touching it but moving up because its SLIME allows it to cling on to the surface around it.
- Land snails that are kept in a tank with a lid on will often climb and hang upside down from the lid. They can do this because the SLIME is sticky and creates SUCTION. Why they like to hang is a mystery. One can only guess that the lid of a tank is slightly more rough and open to the air, providing some kind of natural climbing frame for these molluscs to work out on!
- A giant African land snail has two pairs of TENTACLES. The longest pair carries the eyes, one eye on each STALK. Often called EYE STALKS, the tentacles can disappear quickly into the foot it prodded.
- Land snails do not have good eyesight despite having eyes on the end of STALKS which makes them vulnerable to predators.
- The second pair of TENTACLES is much smaller. These are for smelling and for feeling.
- A land snail can put out one TENTACLE, two, three or all of them at any one time, depending on the environment and what is happening in it.
- Snails have a brain, just like we do, which is split into four parts.
- Snails do not have any hearing which is why their second pair of TENTACLES carry out such an important job as ‘hands’, rather like the hands of a blind person.
- Snails may also ‘hear’ through their foot, detecting vibrations underneath. So, if you are walking down a path, a land snail might hear your steps, retract its body and remain still until you have passed. Of course, it won’t stop you stepping on it …
- We have teeth that cut up food as we eat. A land snail has a rough tongue which has little hooks around it. These hooks, called RADULA, can scrape at hard food which the snail needs to maintain a healthy body.
- Snails love to eat all kinds of plants, fruit and vegetables. They are particularly fond of CUTTLEFISH.
- CUTTLEFISH is very important to snails if you are keeping them as pets. Snail shells are made up of CALCIUM which helps their shells to grow and to become strong, just like children need CALCIUM to make strong bones and teeth. If a snail does not eat CUTTLEFISH or any other form of shell like broken up egg shells, its shell may crack, leaving their foot more vulnerable to predators. Next time you are at the beach, collect cuttlefish and pop them in a safe place in your garden. Leaving them out will be a welcome present to the snails that inhabit your garden though don’t expect to see them munching on them in the day.
- Snails are both male and female and are called HERMAPHRODITES. They are capable of producing both eggs and sperm, but need another snail to make babies.
- When land snails are ready to lay eggs, they make a nest of 4-6 centimetres deep in the soil. They do this by digging a hole in the soil with the tail-end of their foot and laying them there (pond snails on the other hand do not lay their eggs, but carry them around until they hatch).
- When the eggs have been laid they will HATCH after a period of 2-4 weeks, longer if the weather is on the cool side.
- The eggs are creamy-white and about the size of a small pea. They are very delicate and must not be touched. If eggs need to be moved, use a small spoon to pick them carefully out and replace them gently back onto a deep hole.
- The baby snails are born with tiny SHELLS on their backs and FEET that are almost see-through.
- Any eggs that have NOT hatched will be eaten by the babies that have survived. This will give them an extra feed of CALCIUM which will help their own shells grow strong. Recycling in the natural world
- Spring and summer are the best months for laying eggs because these seasons are generally warm and damp. My snails laid eggs at Christmas in 2014 which just shows how mild it was!
- It takes two years for a baby snail to turn into an adult in the UK. Only then can it start having babies of its own.
- A fully-grown adult snail, or one that will not get any bigger, is easy to spot. Look at the open end of the shell. If there is a small lip of shell sticking up, this means that the snail has stopped growing.
- Snails will THRIVE in an environment that is warm and MOIST. Giant African land snails (or GALS for short) originally come from West Africa where the climate is both very wet and humid. Try to recreate this environment if you have them as pets.
- Snails do not like places that are too bright because this will help to dry them out. Never leave a GALS out in sunlight for too long.
- If a snail feels dry it may go inside its SHELL and SEAL up its entrance for protection, a bit like when we go into our houses on an incredibly hot day to keep out the heat.
- When snails are kept in tanks, the inside plastic of the tank should be sprayed with water to keep the tank MOIST. In the summer this might be every day; in the winter, every other day (unless they are hibernating).
- Snails are very active at night. They are known as NOCTURNAL.
- Snails can also be very active on cloudy days when the sun is well-hidden.
- During the winter, snails will HIBERNATE for up to 3 months. You can find garden snails hiding in the garden asleep under planks of wood, up against tree trunks or on fences.
- GALS can live up to ten years, sometimes fifteen if they are looked after well. When they do hibernate, do not think that they have died. I have had many people say to me that they have thrown their snails out because they just seem to disappear for weeks.
- Snails should never be allowed near salt or sugar – they will die if they come into contact with them. If you feel your snail is not well, I can offer two bits of advice: first, if you pick up the shell and the body is tucked inside it, perhaps there is a bit of a smell, then the snail will be dying. In this instance, put it carefully out of its misery by placing it in a jam jar and freezing it. The second piece of advice is this: you pick up your snail and it feels light. Bodies can disintegrate or in fact be eaten by other snails if a snail is not well. If this is the case, do as above. NEVER THROW A SNAIL IN THE GARDEN IF YOU THINK IT IS DEAD. It might not be and you could cause devastation to your green patch.
- Snails have many enemies: beetles, chickens, ducks, geese, birds, toads, turtles and snakes will all eat snails. If you have pet snails, keep them safe indoors. They will enjoy the lawn if you have a cover over them, but no longer than half and hour and stay with them at all times to avoid a predator getting at them.
- Farmers do not like snails. Many gardeners find interesting ways of trapping snails to stop them from eating their vegetables. Copper piping can be effective. There is a substance in copper piping that reacts against SLIME. Giant African, or other, land snails will tend to keep away from it.
- The giant African land snail is one of the most damaging land species in the world because it can attack up to 500 different kinds of plants.
- In America in the 1850s, people imported snails into California for eating. Many snails escaped, had babies and became PESTS because they were able to multiply so quickly and feed off the local vegetation.
- Garden snails can be trapped by setting out jam jars with beer poured into them. The sweetness of the beer attracts the snails which then often drown. Upturned melon skins have a similar effect, providing the gardener is quick enough to dispose of them whilst the snails are busy eating.
- If you do not like garden snails NEVER throw them over the fence or the hedge. Land snails have incredibly good homing instincts. They will always find their way back.
- Garden snails are a DELICACY in some countries. In France, people like to eat them cooked with garlic and oil. African land snails are also popular in West Africa where they are considered a substantial meal, though they do require longer cooking. Other countries where people like to eat snails include Portugal, Greece, Italy and Malta.
- The Ghana Tiger Snail is known to be the largest land snail. It can grow up to 30 centimetres.
- The largest giant African land snail ever recorded was fifteen inches long from head to tail.
- The biggest of all the snails belongs in the sea – an Australian marine type known as a SYRINX ARUANUS. It can grow up to 30 inches long and weighs 40 lbs.
- Here’s an experiment for you: put a snail into a see-through tank and squirt some water onto it. What happens when it starts to climb up the tank? See how the muscles move in its FOOT? Watch how the body moves first and then the shell moves forward on its back – all in SLOMO.
- Take a strong piece of plastic. Make sure that it is damp by squirting it with a little water – not too much. Put a snail onto the plastic where it is damp and, after a minute or two, slowly tip it upside down. Does the snail stay on? Why is it staying on? If the snail begins to slip, wait a little while longer before trying again.
- Put a piece of lettuce onto a plastic surface then place a snail alongside. Hold up the plastic surface and watch if the snail begins to eat. Can you see its mouth?
- Repeat the lettuce experiment but keep the plastic surface on the table. Listen to the noise the snail makes when it is eating. You should hear the ripping noise as the snail’s RADULA tear into the food.
- Repeat this experiment with CUTTLEFISH. If the room is quiet enough you should be able to hear the scraping of the snail’s RADULA on the bone.
- Get hold of a magnifying glass. Carefully hold it up to the snail’s eyes. Caution: try not to get too close or you may touch an EYE STALK and the tentacles will disappear very quickly back inside the body!
- Pick up a snail and place it on your arm, making sure your arm is warm, there is no draught and you are out of sunlight. See how long it takes for the snail to come out and crawl around. Which direction does it go in?
- Now take the snail away and spray some water onto your arm. Put the snail back on your skin. Does it move any faster with the water?
- Now get a piece of cucumber. Carefully slice it in half, or ask a grown-up to help you. Put the cucumber inside the tank and the snail nearby. See how long it takes the snail to smell it and start to move towards it. Do you think the snail is happy?
- Look out for snail trails in the garden or on your lounge carpet if you live in the country. Are they straight? If they aren’t, why do you think they aren’t?
- Make your own snail trail. Get a piece of cardboard, some glue and some silver glitter. With the glue, draw a wobbly line around the card. Cover with the silver glitter and leave to dry. Shake off the excess glue and admire your work.
- Look in the garden after it has been raining. Watch out for the birds poking their beaks into the damp vegetable patch. If you are lucky enough to see a bird with a snail, you will see how the birds make use of their long beaks to try to get at the snail’s soft body – although it is not always such a quick job! If a bird cannot reach the snail’s foot, what else can they do to get at it?
- Draw a snail from underneath by putting it onto a piece of plastic or transparent glass and asking a friend or a parent to hold it up for you. What can you see?
- Whilst the snail is on the glass, see if you can locate its breathing hole which should be near the front of the FOOT. You may need a magnifying glass. You will not be able to see its tongue with the RADULA around it unless you have very sophisticated equipment but you will see the gaping hole that is its mouth.
- Find three different surfaces such as a ruler, a piece of glass and use an arm for the third. Put a snail on each surface, one at a time. Does the snail move quicker on any one surface? If it does, why might that be?
- Arrange a Snail Race with friends. Take a piece of cardboard, any size, and draw lines with a ruler. Try to select snails with different colouring or you may have to mark them in some way, such as by drawing a letter on their shells with a small amount of eco-friendly paint. DO NOT USE NAIL VARNISH. See how long it takes for one snail to make it over the Finish Line! Caution: If you wish to collect garden snails then do so the day before if the race is to be held inside. This way, the snails will have time to get used to the different temperatures away from their natural environment.
University of California, Agriculture and Natural Resources – Integrated Pest Management Program