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All about snails - 11


Land Snails in Popular Culture



The main contribution of snails to the culture of several civilizations, has been their inclusion in their food.


Land snails don’t seem to have a good stigma to them in many cultures due to the fact that they are slow. Most people associate that nature with being lazy and not good for much. The fact that the snail isn’t a lovely animal either means that it gets overlooked when it comes to art and other types of cultural remnants.


Snails are more intelligent though than many people realize. There are stories that depict them as being very strong and self reliant. Those are traits that most people would love to have. The moral of such stories is to explain even though the snail is slow it has a purpose just like every other creature out there. Yet the fact that they aren’t mystical or beautiful has lead to more stories and cultures viewing them as something bad or evil.


In fact, with many early cultures the movements of the snail were viewed as being unclean and they often even marked people with it as a sign of punishment. Yet you will find some great early writings about the snails. For example the Greeks believed that when the snails could be seen climbing the stalks it was time for the harvest to begin. This was a signal to them that it was time to reap the rewards of the foods the gods had allowed them to grow and to live from.


The Aztec believed that the snail was the moon god and that the shell was his protection. They also felt that the appearing of the snail at times and then not at others had to do with the meaning of the rebirth of the moon. Of course we now know that this has to do with them being nocturnal and searching for food at night instead of during the daylight hours.




Most of us are familiar with the works of psychologist Carl Jung. He often talked about interpreting thoughts and dreams. The analogy he refers to with snails is that the shell is the conscious thought process and then the soft part of a snail is the unconscious thought process. Not everyone buys this theory though but the analogy is one that many continue to use today.


There are quite a few references in our language today that refer to snails, but they aren’t in good light. They are meant to mean a very slow process. For example saying someone moves as the pace of a snail or that they are as slow as a snail. The other is called snail mail which refers to mailing something through the post office. We get used to e-mail which allows us instant access so we then become impatient with what takes longer to receive.


Sometimes you will notice snails in books or movies with characteristics that are quite charming. The Disney productions are great at doing this and the charm they put into them helps people to enjoy these animals more. However, they still don’t seem to get the attention or the accreditation in society as so many others.


I mean, when was the last time you saw a business using a snail as their logo? They want to give an image that people relate to in a positive manner. Unfortunately the snail just doesn’t happen to be one of them that fit into that category.  If you can come up with some creative ideas though you may be the one that is able to help change some of the mindsets that people have relating to snails in culture.

All about snails - 10


Land Snails as Food, Escargots



Since prehistoric times, man all over the world consumed what they could for survival, and that sometimes included snails. In several parts of the ancient world including the Roman Empire, snails were eaten frequently. In fact, they were harvested so that there would be a huge supply of them all the time to meet the demand.


That desire to consume them hasn’t stopped there. They continue to be a huge industry for the restaurant business. Offering snails is getting usual for unusual receptions and other elaborate affairs. If you haven’t tried them, the idea may not be very appealing to you. However, you may find that your taste buds are really impressed by them.


Land snails are regularly consumed in the European cuisine. It is no secret that many people find snails to be delicious as an appetizer or as a main course. There are plenty of well known recipes out there for making them and many people do so at home. Such dishes are common in many types of fine restaurants as well.


For example in France they are very popular and they are called with the French word “Escargot”. When cooked, snails are prepared with garlic and parsley butter, added for seasoning and they are server in their own shell. They are very expensive due to the fact that they are considered a delicacy.


In Greece and Italy they are often consumed in a diversity of dishes and sometimes they are even used in sauces and poured over various types of pasta. Other countries like Spain, Portugal and Germany also consume them, where people create a variety of dishes. In the US there is huge market for Escargots where they are imported from many countries. Many of the recipes found in some restaurants are spin offs from what is cooked in the European countries.


Escargot is the common name for snails when they are to be eaten in a dish. Millions of pounds of snails are consumed around the world annually. In fact, there is even a day to celebrate it! May 24th is the National Escargot Day. Recipes like the ones below are cooked that day:


mark    Escargots Gratin


mark    Escargots in Herbed Cream




mark    Escargot a la Bourguignonne


mark    Saffron Tagliarini With Snails & Sorrel


mark    Mushroom & Escargot Soup


mark   Burgundian Escargots With Spaghetti
It is believed that snails for eating were brought to the United States (California) in the 1850’s. Either by immigrants or by consumers, but some of them escaped though and it didn’t take long for them to be all over the country.


Many people viewed them as pests which is why they don’t have any problems eating them. Instead of paying money for them, they started to harvest their own from gardens and farms. In fact, some of the farmers in California were making a nice amount of money on the side by collecting the snails and selling them on the market along with their fruits and vegetables. However, wild snails can carry deadly diseases, therefore regulations in the U.S. to sell and harvest them where established to avoid improper handling.


The most common type of snail used is the garden variety. However, if you have a garden and they are present do not try to trap them and process them yourself. This would be a great way to take care of the problem you are having with the pests harming your fruits and vegetables, but as we mentioned above, wild snails can carry a parasite that can cause meningitis.


As a note of caution it is important to mention that you need to properly cook snails before you consume them, even if they are purchased. The failure to do so can result in parasites entering the body, which have been linked to the development of meningitis. The failure to cook them properly can result in people becoming very ill. When you buy snails to cook you need to prepared them well done, so if present the parasite would be killed.


Before cooking snails, chefs put them on fasting for three days only with water and then feed them with flour and water for one week to purify them. After that, they are cooked with one of the recipes mentioned before.

All about snails - 9


Roman Snail – Helix pomatia



Description



The helix pomatia is very famous because it is the snail used in the exclusive French cuisine where is called “Escargot”. This species of snail is also known as Roman Snail, Burgundy snail or Apple snail.


As we can infer, this snail is edible and highly valued. It has been farmed and it has created an industry to supply restaurants around the world.


The Roman snail is classified as a terrestrial gastropod mollusk.


Anatomy



The Helix pomatia is an air breathing land snail that has a creamy to light brown shell with darker brown bands. The shell is almost rounded with a width of 1.2-2 inches and a height of 1.2-1.8 inches.


They have a single lung and a muscular foot that helps with locomotion. The foot contracts to produce movement and glands within it release a mucus that reduce friction with the underneath surface, reducing risks of damaging their skin.


Another important anatomy characteristic is a couple of tentacles in the head. The upper pair is used for vision, while the lower contains smell sensors.


Helix pomatia information


Roman snail in garden.



Behavior



The trail followed by the Roman snail can be easily followed because they leave behind a mark of slime, which actually is the mucus produced by the foot to ease the movement.


When a helix pomatia moves above dry surfaces, they tend to reduce the foot contact with the surface to avoid the loose of water.


Burgundy snails usually are active during night time, but they can be out on a rainy day or in early mornings, especially if it is a cloudy day.


Habitat and Distribution



This gastropod mollusk also known as apple snail is native of Europe including countries like Austria, Belgium, Germany, Romania, Sweden, Spain, Ukraine, United Kingdom, Luxembourg and most territories in the continent.


However has been moved by humans to Asia, Africa, Oceania and the Americas, where there is a huge industry of snail farming of this and some other edible species.




The helix pomatia habitat usually will be below 2,000 meters above the sea level in places with mild temperature and high humidity. They won’t be find in places with a lot of sun as they cannot tolerate direct sunlight or heavy rains


Roman snail Information


Roman snail or escargot



Diet and Feeding Habits



Usually the feeding activity of a Roman snail will be during the night, but you can find them during early morning hours or during rainy days. To scrap their food, the helix pomatia will use an organ inside its mouth with micro teeth called the radula.


These snails feed on a variety of plants, vegetables, flowers and leaves. However, they need to consume a considerable amount of calcium to preserve their shells as hard as possible and when they are not able to get it from their food, they will feed on some other materials which contain calcium, even soil or rocks.


Reproduction



This snail, as most land gastropods is hermaphrodite; this means that they have both reproductive organs. However, they need to mate with other snails to fertilize their eggs.  During the mating process, both snails will fertilize each other making them both able to release eggs.


The mating process can last for several hours. During that time, both will exchange “love darts”, a calcareus structure that is injected to each other.


Two to eight weeks after mating, they will lay 30 to 50 eggs in holes dug out in the ground with their foot. After 3 to 4 weeks of this, newborn snails will hatch their eggs and will appear out from the soil.


It is believed that this process can be repeated from 2 to 6 times in a year, depending on the climate conditions.


Predators



Roman snails main predators are insects, toads, centipedes, ground beetles, mice and birds, being the eggs the most attacked.


One of the major threats their have, is the continuous habitat destruction. However, they are pretty good surviving and are least concern regarding conservation.


http://en.wikipedia.org/wiki/Helix_pomatia


http://animaldiversity.ummz.umich.edu/accounts/Helix_pomatia/


http://www.iucnredlist.org/details/156519/0

All about snails - 8


Garden Snail – Helix aspersa



Description



The garden snail (helix aspersa) is one of the best-known species of snails in the world. As all terrestrial snails is a gastropod mollusk. It is so common, that it is one of the most proliferated terrestrial mollusks.


The helix aspersa is also known with the common name of “European Brown Garden Snail”, but its scientific name is has alternative versions. Some scientist name this snail as Cornu aspersum, Cantareus aspersus or Cryptomphalus aspersus.


This species is native of Europe but it has been introduced in several parts of the world where it has become a pest for crops and gardens.


Anatomy



The Helix aspersa is an air-breathing snail, which has a single lung. They have a brownish soft body, which is usually covered with slimy mucus.


They have yellow or cream-colored shells with brown spiral stripes. When a snail is old enough, a lip is formed at the edge of the shell aperture. The shell of this species has a height of about 1-1.4 inches and a width of 1-1.5 inches.


The garden snail has a flat muscular organ called a foot that helps it move with a gliding motion helped by the release of a mucus to reduce friction with the rough surface.


This mucus is the reason why snails leave a wet trace of slime when they move around.


Garden Snail Facts


Garden Snail or Helix aspersa



Behavior



Garden snails are mainly active during nights or early mornings when the sun is not shinning, however they can be active during cloudy or rainy days.


Some Helix aspersa hibernate during winter months, especially when they are mature, but they return to activity with the spring.


They are extremely slow as their fastest speed is only 1.3 centimeters per second.


Habitat and Distribution



The Helix aspersa was originally found in the British islands, western Europe and the Mediterraneo, reaching some regions of north Africa, and the middle east.


However, this snail has been introduced to several places where they have become agricultural pests. These places include the United States, Canada, South Africa, Australia, New Zealand, Mexico, Chile, Argentina and some others. This snail has arrived to these places either by accidentally hidden in plant or vegetable shipments or intentionally imported for some purpose.




Diet and Feeding Habits



Garden snails are herbivorous and feed on several kinds of fruit trees, garden plants, crop vegetables and some cereals.


Snail mouth is beneath its tentacles and it has a toothed ribbon called the radula, which is used to fragment its food. This structure is exclusive of mollusks and most of them have one.


Helix aspersa Facts


Close up to garden snail on green background



Reproduction



Like other gastropod mollusks, the Helix aspersa is hermaphrodite; this means that it has both male and female organs. However, mating is required for fertilization, even tough self-fertilization is possible for this species.


The mating process is complex and interesting. After some pairing and courtship, this species start the mating process that can last from four to twelve hours and usually includes the exchange of a love dart, a kind of calcareous arrow with a purpose still unclear.


During the mating process they fertilize each other and they both will lay around 80 eggs 3 to 6 days after the mating occurs. To deliver his eggs, each snail will create a nest digging a hole in the soil with its foot. The nest will be 1 to 1.5 inches deep where the eggs will be delivered.


Gardens snails are able to deliver up to six batches of eggs in a single year. Each newborn, will take one to two years to mature.


Predators



Garden snails are food source for some animals like lizards, frogs and worms. Predatory insects and other species of snails will also eat garden snails.


Some birds, especially ducks will feed on these snails.


Relation with humans



This species is edible and it is sometimes used for cooking, although it should not be confused with the helix pomatia, the “Escargot”.


Although is considered a pest in most places, it has acquired popularity in the cosmetic industry because the regenerative properties of their mucus.





http://www.arkive.org/garden-snail/helix-aspersa/


http://entnemdept.ufl.edu/creatures/misc/gastro/brown_garden_snail.htm


http://www.ipm.ucdavis.edu/PMG/r107500111.html


http://en.wikipedia.org/wiki/Helix_aspersa

All about snails - 7


Giant African Land Snail – Achatina fulica



Description



The Giant African Land Snail is one of the largest of all the terrestrial species out there. It is very rare that you will come across one but if you do pay close attention to the very unique markings that they offer. They have a light to dark brown shells with vertical stripes of a darker shade of brown on them. The average adult shell has a conical shape and its length is 4 inches although exceptional individuals have reached up to inches 7 inches.


They can range in size from about 3 inches long to about 8 inches long. They have an average life span of about 5-7 years. When they have enough food and the weather is comfortable, they tend to live much longer. Some of them have been known to live up to 10 years. It is not easy to have them in captivity because people aren’t usually educated about the temperature and the moisture that they need.


The “Achatina fulica” is considered one of the most invasive species in the world and it is considered by the United States Department of Agriculture as one of the most damaging species for the agriculture and crops in the country. It is known to eat at least 500 different species of plants.


Anatomy



A very important part of the anatomy of this snail is the tongue, which is called the radula. They have small spikes on the tongue that allow it to grab food easily. They are able to sense movement because they don’t have ears. They do have a very good sense of smell though.


They have very powerful foot muscles and this is what allows them to be able to move forward. They also release a slippery substance, a kind of mucus, as they move to help them move through rough materials without damage. Their movements are very slow which is where the saying moving at a snails pace comes in. They often blend in very well to their surroundings though which helps to make up for the fact that they can’t move very fast.


The shell is the location where the Giant African Land Snail takes refuge from predators. They will also spend time inside of their shells when the temperatures begin to dip too low at night for their comfort. While this shell is very hard, it can dry out if they don’t get enough moisture. There are several layers of this shell. Each one has its own process so that the outer shell can be strong. The shell will continue to grow as the snail does for almost one year, when you can guess how big the snail will be.


Behavior



Besides the USDA, several state governments like Idaho, Georgia and Florida among others have listed this species as highly invasive and set controls to avoid their proliferation. The global invasive species database, have listed the Achatina fulica in the top 100 of their rank and associations like invasive.org have made similar warnings.


African Giant Land Snail Facts


Image Courtesy: Roberta Zimmerman, USDA APHIS, Bugwood.org



The Giant African Land Snails don’t seem to interact with each other except for when they are going to mate. They don’t have any sounds and they spend their time moving, eating, and resting.


They are considered to be active between 9 C and 29 C degrees but they are able to survive above 2 C degrees by hibernating inside of the shell during the colder months. During this time, they are able to slow their bodies down enough that they don’t need to eat or to move during that period of time. They can remain inside of the shell for several months before they emerge again.


Sometimes, you will find that these snails may aestivate in the summer months as well. This is caused by drought conditions because their shell will dry out. They are able to keep it moist by creating a barrier with a thin layer of mucus that their bodies create.  In case of severe drought, they are able to aestivate up to three years.


Even so, many experts believe there has to be much more than meets the eye when it comes to these snails. Yet there hasn’t been very much in the way of research conducted on them. Many people would rather spend the time and money investigating other types of animals that seem to be more interesting to the public in general.




Habitat and Distribution



As you may have guessed by the name, The Giant African Land Snail is found in Africa. The Achatina fulica is originally native of East Africa, from Mozambique in the south to Kenia and Somalia in the north. However, they have been introduced in recent years to several locations and seem to have adapted extremely well. These areas include the Caribbean and Pacific islands. They often end up in places where they shouldn’t though due to people transporting them, either as pet trade or inadvertently.


It may surprise you to learn that it is illegal to have one of them in the United States as a pet. This is because they are considered as one of the most invasive species in the world and they have produced great damage to crops in states like Florida, Georgia or Idaho.


While you may think it is no big deal, they can deposit a very large amount of eggs, up to 200 every time they deliver a batch of eggs, and this can happen in a short span of time. Then instead of having one Giant African Land Snail you will have many munching around. Some people turn them loose to get rid of them and that is were the real trouble starts. Instead you should contact your local animal shelter and they can come pick them up.


Diet and Feeding Habits



These snails are herbivorous. They consume a wide variety of plants, fruits and vegetables. They also need calcium in order to ensure their shell stays very strong, so they will consume more of particular types of plants in order to get enough of the calcium they need. When they aren’t able to get enough calcium in their diet from plants, they may feed on bones from carcasses, sand or small stones to get it. They also consume small amounts of water that they can get from the food they consume as well.


Giant African Land Snail - family Achatinidae


Giant African Land Snail / Photo taken by Sonel.SA



Reproduction



The Giant African Land Snail is categorized as a hermaphrodite. This means that they possess the reproduction organs for both males and females.


While you still will need to have two of them for successful breeding, they can take on either role in the process or get them both fertilized, depending mainly on the size difference between the mating couple. They don’t have a set breeding period and on average they lay 5-6 clutches of eggs per year, containing each one close to 200 eggs per clutch with the right conditions.


Delivering close to 1,200 eggs per year and with a hatch success probability of 90%, this species can quickly become a pest.


Predators



It may surprise you to learn who the various predators are of the Giant African Land Snail. They include the caterpillar, ground beetles, other species of snails, and many types of vertebrates.


In Africa, the Giant African Land Snail is considered to be a very delicious source of food. It is nutritional in value and in many areas it is also very expensive. Many villagers will harvest these snails in order to either eat them themselves or to sell them to make money. It is important to note that this particular type of snail has been associated with different types of parasites. The failure to cook them completely can result in humans becoming very ill called meningitis.


Most humans don’t realize how delicate the protective shell of a Giant African Land Snail can be. When a person is holding one it can dry out faster. One way to prevent that is to wet your hands before picking one up to closely examine it. Failure to do so can result in the shells drying up and then these snails don’t have any way to protect their bodies.


Since they also feed on plant life, the use of pesticides is a common cause of death for the Giant African Land Snail. In most areas they are considered to be nothing more than destructive pests. They can affect the quality of foods being grown so preventing them from being in the area often takes drastic measures.

All about snails - 6


How do Land Snails Reproduce?



If you are entering into the world of snails, you will also begin to notice that the way in which they are built has allowed for their survival through centuries.  One of the ways in which this has continued to build is through the abilities to reproduce by these creatures.  The different features in which they can do this also provide them with the capacity to keep slugging on the land.


Reproduction of Snails



Snails will be able to reproduce differently than almost any other type of creature.  This begins with the build that all snails have.  Snails are considered to be hermaphrodites.  This means that every snail will have both male and female reproductive organs.  Most terrestrial gastropods are hermaphrodites. The only snails that have not adapted this attribute are some freshwater and marine species, specifically including Apple Snails and periwinkles.  These two types of snails still have separate male and female individuals.


The land snails will be considered sexually mature from one month and a half to 5 years, depending on species. This is because the life span of most land species does not last for more than five to seven years, allowing for a faster growth rate of the species.  The make-up of the snails will include their reproductive organs on the bottom of their body.  This is close to the front of their body as well, allowing for easier abilities to mate.


The mating practices of snails allow them to deliver eggs for new snails to be brought into life at a consistent rate.  Snails will go through a complete mating ritual with each other, usually which will communicate to the other snail for an average of two to twelve hours.  At the end of this ritual, the pair will fertilize the eggs in the other, so both of them will deliver eggs.  It is known that a snail can carry up to 100 eggs at a time.




When the eggs are fertilized, they will go through a process of growth inside the snail, until they are ready to be delivered. After that, both snails lay their eggs and bury them into separate places inside a small hole made in the topsoil in a cool place. This will allow the eggs to develop without being harmed.


It will typically take a snail egg two to four weeks in order to develop. (1) As soon as they hatch, they will immediately move into a survival mode.  This is because their shells will still be in a weak form.  Their reaction is to find calcium as soon as they hatch by either eating their own egg or eating other eggs in order to get the extra nutrients.  It will take around three months for the snails to completely form and look like a miniature version of an adult snail of their species.  While this takes place, they will stay in a nest that has been built for them, with the transformations being seen through a change in color, from a clear color into a blue then into the adult form that is representative of the species. After the snails are completely developed, they will detach from their parents.


The mating procedure of snails is one that moves through a specific process that helps the species to grow and survive.  This process start from the beginning of sexual maturity, followed by finding the right mate, locating and creating a place to deliver the eggs, hatching of the eggs and ending with the develop of small snails.
1- http://scienceline.ucsb.edu/getkey.php?key=2578

All about snails - 5


Snail Dangers and Predators



One of the main reasons why snails die is due to becoming a meal for other animals. We all know that snails are extremely slow creatures so they definitely aren’t going to be able to out run other animals in the wild. Many of the smaller species of snails end up being consumed by larger ones like the Decollate snail, which is a voracious predator that feeds from garden snails and slugs as well as their eggs. Other common predators include leeches, beetles, and caterpillars.


There is a sort of invertebrate predators of land snails, including beetles, flies, mites, and other snails, while shrews, mice, amphibians, reptiles and birds are the main vertebrate predators.


They have some other predators too that are much larger than these. Depending on where they live they may be eaten by frogs, toads, snakes, and a variety of different birds. Most of them find the snail to be very simple prey and since they are small, eating large numbers of them isn’t uncommon.


In some areas ducks and geese will feed on snails too. Many parks have small ponds where these types of birds reside. They will likely have lots of trees to which provide the shade for the snails as well. Even though these ducks and geese often get lots of food from visitors they still have a natural instinct to find various types of prey including snails out there in the wild.


In many areas domestic pets can be predators for snails as well. They include cats and dogs. They may not need to consume them as food but they are often curious as well as territorial. Some of them may eat them but others simply kill them or just play with them. During some types of the year field mice may be out and they tend to consume snails as well.


Defense Mechanisms



Snails really don’t have much they can do but to hide from predators. The coloring of their bodies offers them a great way to hide. In fact, if you have a garden you may have lots of snails but you don’t see them unless you are actively looking for them. Their only real defense from some predators is the chance to put their entire body inside of the shell. However, many predators are able to break through it anyway.


Thickened shells have been another way to defend from predators as well as an increased secretion of mucus.


Human Danger



Humans are a huge threat to some species of snails. The consumption of them as a type of delicacy is very popular, especially among the upper class. Millions of them are captured and consumed for food annually. However, the majority of snails used for food are grown on snail farms so the actual overall wild population of them isn’t bothered.


This also helps to ensure that healthy snails are the ones that are being available for people to consume. When they are harvested then they are actually fed a special type of diet. This ensures that they will have a better taste than those that you just end up finding in the wild. Of course you will pay more for this type of snail as a food but most people find it to be delicious and well worth it.




With so many predators you may wonder how the snails continue to survive. The fact that they can mate several times per year though is very helpful. The fact that they can also lay up to 100 eggs at a time is another benefit. Even though they have a high mortality rate there are enough of them to help keep the number of snails out there at a decent level.


Many experts feel that the abundance of snails helps to keep other types of animals thriving as well. As you can tell from the list above, there is no shortage of animals that are able to benefit from the consumption of such small forms of life out there.


http://www.carnegiemnh.org/science/default.aspx?id=16822