Giant African Land Snail (Achatina Fulica) — Animals — A-Z Animals

Giant African Land Snail

Giant African Land Snail Facts

Leaves, Vegetables, Fruit, Flowers Predators: Wild Cats, Birds, Humans Special Features: Hard protective shell and have both male and female reproductive organs

Giant African Land Snail Location

Giant African Land Snail

The giant African land snail, is the largest species of snail found on land and generally grow to around 20 cm in length. The giant African land snail is native to the forest areas of East Africa but has been introduced into Asia, the Caribbean and a number of islands in both the Pacific and the Indian oceans.

The giant African land snail is generally seen as a pest as these snails will eat almost anything vegetarian that they can find and have proven to be quite destructive when around crops and wild flowers. Giant African land snails are also known to carry parasites and are illegal to keep as pets in some countries such as the USA.

The giant African land snail is native to humid, forest areas but can today be found in agricultural areas, coast land, natural forest, planted forests, shrublands, urban areas, and wetlands. The giant African land snail is seen to be highly invasive species and large colonies of land snails can be formed from just one individual.

Giant African land snails have both male and female reproductive organs. Although giant African land snails primarily mate with one another, in more isolated regions the giant African land snail is capable of reproducing by itself. Giant African land snail lay around 6 clutches of eggs every year, laying an average of 200 eggs per clutch. Around 90% of snail hatchings survive meaning that a snail free area can quickly become infested.

Giant African land snails are active during the night and spend the daytime hours safely buried underground. Giant African land snails reach their adult size by the time they are 6 months old and although their growth rate slows at this point, giant African land snails never stop growing. Most giant African land snail reach between 5 and 6 years of age but some giant African land snail individuals have been known to be more than 10 years old.

During periods of extreme drought, the giant African land snail goes into aestivation (summer sleep). The giant African land snail seals itself inside its shell to retain water and giant African land snails do this about 3 times a year, depending on the areas in which they inhabit.

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Snail Facts and Information

Facts about Snails

There are some very interesting facts about snails that can help you to see them in a different way.

Snail Information

Facts and Information about Snails, Habitat, Anatomy, Reproduction, Feeding and Predators

Types of Snails

There are thounsands of snail species, but a few of them are widely known as the Garden Snail or the Roman Snail

Humans and Snails

The relation between humans and snails is complex and ranges from being cultivated to being pest

Snail Facts and Information

Snail Facts and Information. Habitat, Feeding, Anatomy, Reproduction, Lifecycle, Predators.
Facts about African Giant Snail, Garden Snail, Roman Snail or Escargot. Get Started ›

Introduction

Snails’ ancestors are one of the earliest known types of animals in the world. There is fossil evidence of primitive gastropods dating back to the late Cambrian period; this means that they lived nearly 500 million years ago.

There are many types of snails, but they fundamentally differ because they are aquatic or terrestrial. The former are adapted to live in the sea or bodies of fresh water, but the latter live exclusively on land, although in humid areas.

All land snails are gastropod mollusks, meaning that they belong to the same group of octopuses, which are part of the phylum Mollusca. At the same time, they are members of the class Gastropoda, which includes all snails and slugs. Being a mollusk means lacking an internal skeleton and bones, but snails are not unprotected.

Gastropods can adapt to a variety of living conditions, and they don’t require large amounts of food. They have been able to continually evolve to survive the conditions around them which many researchers find to be very fascinating.

Gastropods belong to the phylum Mollusca (or Mollusks) a classification of invertebrate animals with a soft unsegmented body, sometimes covered with an exoskeleton or shell. This phylum, Mollusca, includes animals like squids, octopuses, clams and cuttlefishes among others. Snails and slugs are both Gastropods. Therefore they are closely related, regardless the fact that slugs lack a protective shell.

Being a Gastropod

The most striking physical feature of snails is their spiral shell that they load on the back. It is a hard structure composed of calcium carbonate, which protects their soft body and internal organs. Among these organs is their lung because land snails breathe air from the atmosphere that then passes into a lung to get the oxygen; this is one of the main differences with aquatic snails, that only a few species of water snails breathe air.

You will find snails everywhere around the world. In fact, Gastropods range second, only behind insects when it comes to the number of named species. As an obvious result of this, they are found in many locations, living in a very diverse type of habitats and even having particular feeding habits.

The Earth offers a vast diversity of habitats for snails. Surely you have found tiny snails under a stone, but also climbing some stem or leaf of a plant. They can survive in natural environments or places frequented by humans, such as public parks and gardens.

Their quantity and diversity are vast. There are anything between 85,000 and 150,000 mollusks of which 80-85 percent are gastropods. Therefore, the world is home to more than 60,000 species of them.

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Land snails range greatly in size. While some of them are only a few inches long and often weigh only a few ounces, there are land snails that reach almost 12 inches, like the Giant African Land Snail, a species endemic to Africa.

Although snails do not have legs, they can move thanks to a “muscular foot” that, based on wave movements, allows the snail to go from one place to another. This action is smoother and safer for snails with the help of the “mucus” that the snail secretes to slide on all types of surfaces and maintain its moisture reduces friction and avoids harms to their body.

Certainly, land snails are incredibly slow. Their forward speed depends on the species, but usually, it is between 0.5 and 0.7 inches per second. Its slowness is another feature that has made it famous, and some people have known how to play with it. For example, in many places in the UK, snail racing is organized! Can you imagine waiting for them to reach the finish line? It does not last as long as it may seem.

While moving, snails leave behind a trail of slime, a lubricant they produce to allow them to go on any terrain without injuring its body. Land Snails aren’t able to hear at all, but they have eyes and olfactory organs. They use their sense of smell to help them find food being their most important sensory organ.

You will find that snails are most active at night. They may come out during the early morning hours as well.

The biological features of snails are fascinating. For example, most are hermaphrodites, which means that a single snail has male and female reproductive organs at the same time. However, they usually mate in the “traditional” way: with a partner. A few weeks after mating and laying eggs, the hatchlings emerge from their egg, small and defenseless against many predators that sneak around, such as beetles, birds, turtles and even other snails. There are exceptions. Some species have sex differentiation, so every individual is either male or female.

The life expectancy of snails in the wild is about 3 to 7 years, but in captivity, they can live up to 10-15 years or even more.

Snail shell is made of calcium carbonate and keeps growing as long as the snail grows. They keep adding more calcium carbonate to the edge until the snail reaches adult size.

Humans have eaten land snails for centuries, although not everywhere. They are common in gastronomy, in some parts of Europe like France and Spain where they are considered a delicacy. However, their consumption must be careful, since some snails harbor parasites that, once in the human body or that of other animals, can cause severe diseases. Therefore, handling land snails, especially those found in the wild, should observe the proper hygiene precautions to avoid dangerous diseases like meningitis among others.

When snails multiply and damage crops or in some way affect the species of a region or the human being, they are considered pests. Certain species grow up to the size of an adult hand, and of course, their feeding needs also increase. That is why it is important to pay attention to the recommendations about the handling and care of snails.

In conclusion, snails are much more than a shell. On this site, we talk about land snails. Therefore we implicitly exclude freshwater and sea snails and refer only to the terrestrial gastropod mollusks that have shells.

Definitions:

Cambrian period A period of the Paleozoic era, from 540 to 585 million years ago.

Invertebrate. Animals that do not have a vertebral column.

Exoskeleton. External skeleton that protects the body of an animal.

Hermaphrodites A living organism that has reproductive organs of both sexes.

Top Facts about Snails

  • The largest land snail recorded was 12 inches long and weighed near 2 pounds.
  • Garden snails (helix apersa) a top speed of 50 yards per hour, this is about 1.3 cm.

Snail FAQs

Snails tend to feed on a variety of items found in their natural habitat. What they will actually consume depends on where they live and the species of snail that they are.

Snails for Kids

  • Snails are so diverse that there are land snails, sea snails and freshwater snails.
  • There are thousands of species of snails.

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Snail Life Cycle

Life cycle of a Land Snail

The life cycle of any animal is the period involving the succession of one generation to the next through reproduction.

In brief, the snail life cycle has the following steps:
1. Born and develop.
2. Reach sexual maturity.
3. Find a partner to mate.
4. Mating process.
5. Gestation period.
6. Egg dropping.
7. Egg hatching.

The age of sexual maturity is variable from 6 weeks to 5 years, depending on species of snail. The breeding process of snails has some unique features when compared to other land animals.

Reproduction of land snails is carried out under odd circumstances. First, most of these gastropod mollusks are hermaphrodites so that a single snail may have male and female reproductive organs. Second, on most occasions, two individuals copulate rather than self-fertilize. And third, they have the habit of shooting some structures called “love darts” just before mating.

Mating and beyond

Land snails engage in various types of courting rituals to attract mates. They can last breeding from a couple of hours to half a day.

They don’t make sounds to lure each other like many types of animals do because snails don’t have the ability to hear. So they expel some chemicals to attract others ready to mate and use touching as a way of courting. Once the mating is over, they go in separate directions.

Snails will produce around 100 eggs, but some species can have up to 400.

Snail breeding involves sexual reproduction. During copulation, both individuals can transfer sperm to each other, but it does not happen in all cases. The sperm is transferred using a penis or spermatophore exiting the body during the intercourse. Then, the sperm enters the body of the other snail to fertilize the eggs later.

Even though snails are hermaphrodites, they mate in the traditional way, they do not fertilize themselves. However, after the mating, both snails can deliver a set of eggs which increases the chances of survival.

When fertilization occurs, eggs develop. Laying the eggs happens in the following days, but the time varies according to the species. As they are promiscuous animals, they can store sperm from previous couples for a long time, even years.

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After the mating process, both snails will produce around 100 eggs, but some species can have up to 400. These eggs are tiny, and they will be dropped into moist soil and covered. It can take up to four weeks for them to hatch.

Before laying their eggs, some snails build a nest in a hole, between vegetation or on the ground. If it is in the soil, the animal digs with the aid of its ventral foot until obtaining a hole with a depth of 2 to 4 inches. Once the snail has the proper place, it puts the 100 small and round eggs, often white, surrounded by a viscous layer that serves as protection. They usually have a diameter between 3 and 6 millimeters.

Even with so many eggs produced, only a fraction of these snails reach maturity. Many of the eggs are washed away by rain or water or eaten by predators, despite the outer protective layer and being resistant to cold and heat. Even humans take them, which are known as white caviar or snail caviar, consumed in some regions of the world.

Land snails can lay eggs once a month.

From breeding to adulthood.

The shell of the snail develops since it is an embryo inside its egg. Under favorable conditions, eggs hatch after approximately two weeks to 1 month and snails emerge with a soft shell. Therefore, they need to feed themselves to get calcium, and the first source to get it is by consuming the remains of their egg and even other eggs that have not yet hatched.

Shells continue to grow with the snail over the course of its life.

The baby snails have, in addition to a soft shell, an almost transparent body that acquires strength and color as it grows. The first color they usually have is bluish but then turns to brown or the color that characterizes their species. They grow remarkably fast, but very few reach one year of age. In general, snails are victims of numerous predators, and young individuals are even more vulnerable because of their incomplete development.

Shells continue to grow with the snail over the course of its life, and the rings it has are indicators of their age.

The whole life cycle of a land snail is not very long in human terms. A single snail can live 2 to 7 years according to its species, but in captivity, the life expectancy extends to 10 or 15. In few occasions, they live longer.

Stopping and hibernating

Some land snails enter a period of lethargy in which they decrease their metabolic rate, and both respiration and heart rate become slower than usual. If it happens in summer is called estivation, but if it occurs in winter, it is hibernation. During this process, to keep their moisture and protect from predators, snails retract into their shell and secrete a layer of mucus called epiphragm, which closes the opening.

Some young snails show a tendency to remain near the place where their eggs hatched, and if they go away, return there in the mornings.

Sources:

Animals, a visual encyclopedia. Second edition. Smithsonian 2012.

BioExpedition Publishing © 2017.

www.snail-world.com

Vaquita

The world’s smallest porpoise is also the rarest marine mammal on Earth. This diminutive animal is a critically endangered species of cetacean, a taxonomic clade used to describe whales, dolphins, and porpoises. Read on to learn about the vaquita.

Description of the Vaquita

This comparatively tiny marine mammal is four and a half feet long on average, and only slightly longer than your average golden retriever from nose to tail! These torpedo-shaped marine mammals are dark gray, with a light or white underbelly, and large dark patches around each eye. Vaquitas have a small dorsal fin on their backs, two pectoral fins (one on either side of the body), and a tail fin, also known as a fluke.

Interesting Facts About the Vaquita

This incredibly rare little porpoise has been getting attention in the media due to its precarious population numbers. Relatively little is known about it, simply because individuals are incredibly hard to find to conduct research. Continue reading to learn what little we do know about these mysterious marine mammals.

  • What’s in a Name? – The vaquita’s name is reflective of their home range in Mexico’s Gulf of California. In Spanish, vaquita means “little cow.”
  • Recent Discovery and Impending Extinction – Vaquitas were discovered fairly recently, with the first individuals officially recorded in 1958. Unfortunately, since the time of their discovery, this animal’s population has dropped an estimated 95%. In 1997, the vaquita population was believed to be 567 individuals, but as of 2017 that number has dropped to just 30 animals.
  • VaquitaCPR – An emergency conservation project called VaquitaCPR was launched in 2017. The goal of the group was to capture the remaining individuals and create a captive breeding program to save the species. Unfortunately, the animals did not respond well to the change in environment, and the project was abandoned when a female vaquita passed away. The project has now focused all its efforts on a complete ban of gillnet use in this animal’s habitat.

Habitat of the Vaquita

The vaquita lives and feeds in shallow coastal waters, exclusively in the Gulf of California. They prefer shallow water, as their favorite food sources are bottom-dwelling fish (also known as “benthic”).

Distribution of the Vaquita

The vaquita is restricted to an extremely small range. This unique porpoise is found only in the northern end of the Gulf of California, and nowhere else in the world.

Diet of the Vaquita

Vaquitas eat a variety of fish, squid, crabs, and other crustaceans. Examination of the stomach contents of deceased animals indicates that they have a varied diet. One animal studied was found with 17 different species of fish in its stomach.

Vaquita and Human Interaction

The plight of the vaquita is a bitter one, as populations have been decimated nearly exclusively by fishing for a type of fish called “totoaba.” The totoaba is itself endangered, and totoaba are illegally hunted solely for their swim bladder. This swim bladder is highly valued on the Chinese black market as a form traditional medicine, despite a lack of proof of any actual medicinal value.

The totoaba are captured using gill nets, which are designed to entangle the gills of fish and trap them. Vaquitas get caught in these nets and are unable to return to the surface to breathe. Because vaquitas are mammals, not fish, they drown when trapped under water, and are simply tossed overboard by the fishermen when they bring up the nets. Totoaba fishing has been suspended, but many poachers continue to illegally hunt the fish, and in the process they are killing off the last of the vaquita. It is estimated that there are only 30 left in the world.

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Domestication

Vaquita are extremely rare and have not been domesticated.

Does the Vaquita Make a Good Pet

There are simply not enough vaquita left in the world to be kept as pets. They are critically endangered.

Vaquita Care

We know very little of vaquita behaviors and needs. The only attempt to keep them in human care – a last-ditch effort to save the species – failed to keep them alive in sea pens. We know they eat a variety of fish, squid, and crustaceans, but not much else about their needs.

Behavior of the Vaquita

These marine mammals are described as shy, and frequently avoid any contact with boats. Unlike many other species of porpoise, they do not travel in large groups. In the vast majority of sightings, vaquita are spotted alone or in pairs. They do not appear to engage in any above-water acrobatics, as some other species of cetaceans do.

Reproduction of the Vaquita

Very little is known about vaquita reproduction, mainly because of their minimal numbers and secretive behavior. Scientists estimate much of their reproductive information from the harbor porpoise, which is a close relative. It is believed they reach sexual maturity at around 3 to 5 years of age. Gestation is estimated to be about 11 months, and calves likely nurse for up to 8 months.

A Final Word on the Vaquita

Healthy populations rely heavily on genetic diversity. When genetically diverse (not closely related) individuals reproduce, they are less likely to have adverse mutations or infertility. In populations with low genetic diversity, the likelihood of inbreeding increases, and the offspring are less likely to survive and be able to reproduce.

Because the population is so small, scientists believe that the lack of genetic diversity makes it virtually impossible for the species to rebound. Essentially, it is very likely that this shy animal will go extinct. Vaquita populations were decimated in just 20 years. The impact of unregulated overfishing to a single species can be immense, and sometimes the added protections come too late and are ineffective.

Let this animal’s story be a warning to our next generation, and a beacon of hope for future change. Countries have to work together to successfully protect species, and research must be done to determine how to effectively increase population numbers. Hopefully future generations of scientists can continue to improve their methods, and develop innovative ideas for species protection. From cute porpoises, to not-so-cute totoabas, the loss of any species can adversely impact any ecosystem.

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Snail Habitat and Distribution

A home for snails

Snails are practically everywhere. You have probably seen some in your garden or on the surface of a wall, defying gravity.

Snails are mollusks belonging to the class Gastropoda, whose members, slugs and snails make up 80 percent of all mollusks. The gastropods live throughout the world, from the Arctic and Antarctic oceans to the equatorial regions. Also, some species have adaptations to survive in the water and some others on land.

For their part, land snails are among the most widely distributed invertebrates around the world. They can be found on five continents and even in the sub-Antarctic region, where temperatures are very low. Only in North America exist more than 500 native species, and these coexist with other species introduced or that came from other places.

Assorted habitats

As we said, snails are present in most of the world, so it is not a surprise to discover that they dwell in diverse habitats. Some of them are comfortable in the desert while others live in ditches and cooler climates. These include mountain areas and even marshes.

Some people assume that snails do not live in the desert, but that isn’t true. The terrestrial gastropods are the only mollusks that have adapted to all the habitats of the Earth. They dwell in areas of high altitude, mountainous regions, hot and cold places.

Land snails live and perform their vital functions on the ground and not in the sea or bodies of fresh water. However, sometimes the line between aquatic and terrestrial species is thin since some prefer humid sites, and some others are almost amphibian.

They can survive in both natural and urban areas, or uninhabited environments. Common places that land snails inhabit are gardens, fields, agricultural areas, river banks or streams, suburbs, swamps, cities, jungles, and forests. Often, house gardens are home to many snails, and as they are easy to maintain, some people keep them as if they were farm animals, although this activity is typically done to use snails as food.

Thanks to the fluid they secrete, snails can move on all types of surfaces, so it is common to see them on walls, ceilings, rocks, plant leaves, mosses and cracks in any area. Many prefer to stay close to the rocks, ditches, and plants to have a place to protect themselves from their natural predators.

Super Snails

While it is true that most prefer humid sites, some snails can survive the harsh conditions of the deserts. Among these species are the little known Sphincterochila boissieri and Xerocrassa seetzeni. The former lives in the deserts of Egypt and Israel, and the latter is distributed from Syria to Saudi Arabia in the Negev desert, an area uninhabitable to people and many animals, but not for them.

The species Notodiscus hookeri dwells in the sub-Antarctic region, specifically in the islands and archipelagos of the Atlantic Ocean: The Kerguelen Islands, Crozet Islands, Prince Edward Islands, Heard and McDonald Islands and the South Georgia group.

Some birds such as the Great Tit (Parus major) carries snails in its plumage, a fact that suggests that these small gastropods can be transported from habitat to habitat in an unintentional way.

It is clear that snails are abundant, but some are at risk of disappearing from some areas, and others are taken out of their natural habitat for practical purposes. In some cases, it has been counterproductive, as with the Giant African Snail (Achatina fulica), introduced to many areas of the world and now considered one of the most dangerous invasive species due to its habit of consuming crops.

The snails in your backyard are very resilient animals, even if they do not look so.

Sources:

BioExpedition Publishing © 2017.

www.snail-world.com

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