Heliciculture
Encyclopedia
Heliciculture, or snail farming is the process of farming or raising land snail
s specifically for human consumption, and more recently, to obtain snail slime
for cosmetics
use.
Perhaps the best known and most often cultivated land snail species in the Western world
is Helix pomatia
, the Roman snail, Burgundy snail or apple snail. Another species eaten is Helix aspersa
. Both of these land snails are European in their native range.
Other species of land snail that are consumed by humans are found in Europe, Northern Africa, North America and in various other parts of the world.
Roasted snail shells have been found in archaeological excavations, an indication that snails have been eaten since prehistoric times.
In ancient Rome
, snails were fattened up in "cochlear" gardens before they were eaten. The Romans, in particular, are known to have considered escargot as an elite food, as noted in the writings of Pliny
. For example the species Otala lactea
of edible snails has been recovered in archaeological excavation from Volubilis
in present day Morocco
. "A Virginia Farmer" described keeping snails in a cool, moist and shady environment, supplying artificial dew if necessary, containing them on an "island" surrounded by water to prevent escape, supplying vegetation as feed, and fattening them on corn meal.
Pliny
described the snail garden of Fulvius Hirpinus 2,000 years ago as having separate sections for different species of snails. Hirpinus allegedly fed his snails on meal and wine. But note, stale beer placed in a shallow dish is a way of killing them. Snails are attracted to the yeast in beer and will crawl into the dish and drown.
The Romans selected the best snails for breeding. "Wall fish" were often eaten in Britain, but were never as popular as on the continent. There, people often ate snails during Lent, and in a few places, they consumed large quantities of snails at Mardi Gras or Carnival, as a foretaste of Lent
.
According to some sources, the French imported brown garden snails
to California in the 1850s, raising them as the delicacy escargot. Other sources claim that Italian immigrants were the first to bring the snail to the United States.
, Indonesia
, Greece
and China
. The U.S. exported live, fresh, chilled, or frozen snails worth $55,000 to 13 countries; most were shipped to Japan
, the Netherlands, and the United Kingdom
. Individual statistics are not available for U.S. exports of prepared or processed snails from the U.S. Department of Commerce.
Edible land snails range in size from about one mm long to the giant African snails, which occasionally grow up to 312 mm (12¼ in) in length. "Escargot" most commonly refers to either Helix aspersa
or to Helix pomatia
, although other varieties of snails are eaten. Achatina fulica, a giant African snail, is sliced and canned
and passed off on some consumers as escargot. Terms such as "garden snail" or "common brown garden snail" are rather meaningless since they refer to so many types of snails, but they sometimes mean H. aspersa.
s. Although they have both male and female reproductive organs, they must mate with another snail of the same species before they lay eggs. Some snails may act as males one season and as females the next. Other snails play both roles at once and fertilize each other simultaneously. When the snail is large enough and mature enough, which may take several years, mating occurs in the late spring or early summer after several hours of courtship
. Sometimes there is a second mating in summer. (In tropical climates, mating may occur several times a year. In some climates, snails mate around October and may mate a second time 2 weeks later.) After mating, the snail can store sperm received for up to a year, but it usually lays eggs within a few weeks. Snails are sometimes uninterested in mating with another snail of the same species that originated from a considerable distance away. For example, a H. aspersa from southern France may reject a H. aspersa from northern France.
s, millipede
s, etc. Dry soil is not suitable for the preparation of a nest, nor is soil that is too heavy. In clay soil that becomes hard, reproduction rates may decrease because the snails are unable to bury their eggs and the hatchlings have difficulty emerging from the nest. Hatchability of eggs depends on soil temperature, soil humidity, soil composition, etc. Soil consisting of 20% to 40% organic material is good. Keep the soil 65 °F to 80 °F (18 °C to 27 °C), best around 70 °F (21 °C). Maintain soil moisture of 80%. One researcher removes eggs immediately after they are deposited, counts them, then keeps them on moist cotton until the eggs hatch and the young start to eat. Snails lose substantial weight by laying eggs. Some do not recover. About one-third of the snails will die after the breeding season.
H. pomatia eggs measure about 3 mm in diameter and have a calcareous
shell and a high yolk content. H. pomatia lays the eggs in July or August, 2 to 8 weeks after mating, in holes dug out in the ground. (Data varies widely on how long after mating snails lay eggs.) The snail puts its head into the hole or may crawl in until only the top of the shell is visible; then it deposits eggs from the genital opening just behind the head. It takes the snail 1 to 2 days to lay 30 to 50 eggs. Occasionally, the snail will lay about a dozen more a few weeks later. The snail covers the hole with a mixture of the slime it excretes and dirt. This slime, which the snail excretes to help it crawl and to help preserve the moisture in its soft body, is glycoprotein
similar to eggwhite.
Fully developed baby H. pomatia snails hatch about 3 to 4 weeks after the eggs are laid, depending on temperature and humidity. Birds, insects, mice, toads and other predators take a heavy toll on the young snails. The snails eat and grow until the weather turns cold. They then dig a deep hole, sometimes as deep as 1 foot (0.3048 m), and seal themselves inside their shell and hibernate for the winter. This is a response to both decreasing temperature and shorter hours of daylight. When the ground warms up in spring, the snail emerges and goes on a binge of replacing lost moisture and eating.
In warm, damp climates, H. aspersa may lay eggs as often as five times from February through October, depending on the weather and region. Mating and egg-laying begin when there are at least 10 hours of daylight and continue until days begin to get shorter. In the United States, longer hours of sunlight that occur when temperatures are still too cold will affect this schedule, but increasing hours of daylight still stimulate egg laying. If warm enough, the eggs hatch in about 2 weeks, or in 4 weeks if cooler. It takes the baby snails several more days to break out of the sealed nest and climb to the surface. In a climate similar to southern California's, H. aspersa matures in about 2 years. In central Italy, H. aspersa hatches and emerges from the soil almost exclusively in the autumn. If well fed and not overcrowded, those snails that hatch at the start of the season will reach adult size and form a lip at the edge of their shell by the following June. If you manipulate the environment to get more early hatchlings, the size and number of snails that mature the following year will increase. In South Africa, some H. aspersa mature in 10 months, and under ideal conditions in a laboratory, some have matured in 6 to 8 months. Most of H. aspersa's reproductive activity takes place in the second year of its life.
takes 6 to 16 months, depending on weather and the availability of calcium
. This snail lives 5 or 6 years, sometimes as many as 9 years.
Several factors can greatly influence the growth of snails including: population density; stress [snails are sensitive to noise, light, vibration, unsanitary conditions, irregular feedings, being touched, etc.]; feed; temperature and moisture; and the breeding technology used.
H. aspersa requires at least 3% to 4% calcium in the soil (or another source of calcium) for good growth. Most snails need more calcium in the soil than H. aspersa. Low calcium intake will slow the growth rate and cause the shell to be thinner. Calcium may be set out in a feeding dish or trough so the snails can eat it at will. Food is only one calcium source. Snails may eat paint or attack walls of buildings seeking calcium, and they also will eat dirt.
A newborn's shell size depends on the egg size since the shell develops from the egg's surface membrane. As the snail grows, the shell is added onto in increments. Eventually the shell will develop a flare or reinforcing lip at its opening. This shows that the snail is now mature; there will be no further shell growth. Growth is measured by shell size, since a snail's body weight varies and fluctuates, even in 100% humidity. The growth rate varies considerably between individuals in each population group. Adult size, which is related to the growth rate, also varies, thus the fastest growers are usually the largest snails. Eggs from larger, healthier snails also tend to grow faster and thus larger.
Dryness inhibits growth and even stops activity. When it becomes too hot and dry in summer, the snail becomes inactive, seals its shell and estivates
(becomes dormant) until cooler, moister weather returns. Some snails estivate in groups on tree trunks, posts, or walls. They seal themselves to the surface thus sealing up the shell opening.
Peak snail activity (including feeding and thus growth) occurs a few hours after sunset, when the temperature is lower and the water content (in the form of dew
) is higher. During daytime snails usually seek shelter.
), temperature (thermometer
), soil moisture, and light (in foot candles); a weight scale and an instrument to measure snail size; a kit for testing soil contents; and a magnifying glass to see the eggs. You also may need equipment to control the climate (temperature
and humidity
), to regulate water (e.g., a sprinkler system to keep the snails moist and a drainage system), to provide light and shade, and to kill or keep out pests and predators. Some horticultural systems such as artificial lighting systems and water sprinklers may be adapted for snail culture. You will have better results if you use snails of the same kind and generation. Some recommend putting the hatchlings in another pen.
Four systems of snail farms can be distinguished:
Moisture: Snails thrive in damp but not waterlogged environments and thus a well-draining soil is required. Research indicates that water content around 80% of the carrying capacity of the soil and air humidity
over 80% (during darkness) are the most favorable conditions. Many farmers use mist-producing devices
to maintain proper moisture in the air and/or soil.. Also, if the system contains alive vegetation, the leaves are to be periodically wet.
Soil
: Snails dig in soil and ingest it. Good soil favors snail growth and provides some of their nutrition. Lack of access to good soil may cause fragile shells even when the snails have well-balanced feed; the snails growth may lag far behind the growth of other snails on good soil. Snails will often eat feed, then go eat dirt. Sometimes, they will eat only one or the other.
A well-functional soil would have the following characteristics:
Soil care: A farmer must find a way to prevent the soil from becoming fouled with mucus and droppings and also tackle undesirable chemical changes
that may occur in time.
Soil mix suggestions:
(APHIS
) Standards for Snail-Rearing Facilities were revised March 2001 and are available at http://www.aphis.usda.gov:80/ppq/permits/plantpest/rearing.pdf
Enclosures for snails are usually long and thin instead of square. This allows you to walk around (without harming the snails) and reach in the whole pen. The enclosure may be a trough with sides made of wood
, block, fiber cement sheets, or galvanized sheet steel. Cover it with screen
or netting
. The covering will confine the snails and keep out birds and other predators. Fences or walls are usually 2 foot (0.6096 m) high plus at least 5 inches into the ground. Fencing made of galvanized metal or hard-plastic sheets helps keep out some predators. A cover will protect against heavy rain. Shade (which may be a fine mesh screen) on warm winter days helps keep the snails dormant. Use 5 mm mesh or finer for pen screens or fences. Pens containing baby snails will need a finer mesh.
Snails like hiding places, especially during the warm daytime. For example, purchase plastic soil drainage pipes from the local garden center, split them in two lengthwise, and stack one layer one way and the next layer at a right angle. This will provide shelter and will increase by 50% the number of snails you can put in the pen.
A sprinkler system will ensure moisture when needed. Turn it on at sunset. If turned on early in the day, the moisture may drive snails out into hot sunshine. Monitor temperature and humidity using a thermometer and a hygrometer.
Although you can use fencing for the enclosure's sides, the bottom, if not the ground or trays of dirt, must be a surface more solid than screening. A snail placed in a wire-mesh-bottom pen will keep crawling, trying to get off the wires and onto solid, more comfortable ground.
Preventing escapes: In an open pen, curve the top of the fences inward in a half circle to confine the vineyard snail. H. aspersa will escape from such an open pen, so you could use an electric fence to contain them. [The electric fence
top has two or more thin wires that are 2 to 4 mm apart. Each wire carries the opposite charge of the wire next to it. Use a battery or transformer to supply 4 to 12 volt
s to the wire. A snail will get a mild shock and retract when it crawls over a wire and touches a second wire.]
Another technique to confine snails is to bend the fence top inward into a sharp "V" shape with about a 20 degree angle. The snail's shell will hit the bent-back part of the screen before he can reach up and start crawling on it. This blocks him, and the angled screen automatically compensates for the size of the snail.
Another alternative, especially handy for solid wall enclosures, is to attach to the wall a horizontal piece of screen that projects inward several inches over the enclosure. Make the screen with material like nylon monofilament that is moderately stiff and springy yet easily flexible. On the inside edge of the screen, remove the cross fibers until you've created a fringe several inches wide. As the would-be escapee crawls on the underside of the screen and moves out onto the fringe, his weight pulls several individual fibers down. One by one, another fiber gets away from the snail and springs back up out of reach. Eventually the snail is dangling by a thread. He then falls because the surface area is not big enough to crawl on.
Since snails usually will not cross a copper
band, another solution is to top the fence with 3-inch-wide (or wider) copper band. You could bend the band so that part of it faces inward and is parallel to the pen floor. If the band is placed too close to the ground, rain may wash soil against the copper and leave a residue that may enable the snail to cross it. Also, be sure to bury the bottom of the fence deep enough into the ground so that the snails don't dig under it.
Pens with gardens: An alternate method is to make a square pen with a 10 feet (3 m)-square garden in it. Plant about six crops, e.g., nettles and artichokes, inside the pen. The snails choose what they want to eat. If it has not rained, turn sprinklers on for about 15 minutes at dusk, unless the snails are dormant. A disadvantage to this method is that, if the snails are not mature at the end of the year, it is difficult to replant fresh plant crops in the pens.
Plastic tunnels make cheap, easy snail enclosures, but it is difficult to regulate heat and humidity. The tunnel will be 10 to 20 warmer than the outside, and snails become dormant as the temperature climbs above 80 °F (27 °C.
Indoor pens: With snails raised indoors under controlled conditions, reproduction varies according to the geographic origin of the breeding stock. For example, one researcher found that H. aspersa snails from Brittany
seem to do better indoors than snails from another region. To breed snails indoors, keep the temperature at 70 °F and the relative humidity at 80% to 90%; some sources say 95%. Another source recommends 75% humidity by day and 95% at night. The Center for Heliciculture once recommended 65-75% humidity during the day and 85-95% at night at 68 F. In any event, avoid humidity higher than 95% (some say 90%) for any length of time. Excessive humidity can kill snails. Optimum temperature and relative humidity depend on several things, including the snail variety and even where breeding stock was gathered. For H. aspersa, the optimum temperature for hatching eggs seems to be 68 °F (20 °C)at 100% relative humidity. The second best temperature/humidity combination depends on where the snails came from and results can drop drastically to 0% hatching at 17 °C (63 °F) and 100% humidity. Err on the side of a few degrees warmer or a small percentage dryer. Do not keep the soil wet when the humidity is maintained at 100%, as the eggs will absorb water, swell up, and burst.
Use fluorescent lights to give artificial daylight. Different snails respond differently to day length. The ratio of light to darkness influences activity, feeding, and mating andegg-laying. Eighteen or more hours of light apparently stimulate H. aspersa growth, while less than 12 hours inhibit it. Some snail species may associates the long hours of light with the start of summer—the peak growing season. Eighteen hours of daylight also appear optimal for breeding (mating and egg laying), but snails will breed in darkness.
Breeding boxes and cages: Snails can be bred in boxes or cages stacked several units high. Use an automatic sprinkler system to provide moisture. Breeding cages should have a feed trough and a water trough. Plastic trays that are a couple of inches deep are adequate; deeper water troughs increase the chance of snails drowning in them. These trays may be set on a bed of small gravel. Fill small plastic pots, e.g., flower pots about 3 inches deep, with sterilized dirt (or a loamy pH neutral soil) and set them in the gravel to give the snails a place to lay their eggs. Remove and replace each pot after the snails lay eggs. (Set one pot inside another so that you can easily lift one out without shifting the gravel.)
After the snails have laid their eggs, put the pots in a nursery where the eggs will hatch. Keep the young snails in the nursery for about 6 weeks. Then move them to a separate pen as young snails do best if kept with other snails of similar size. Eight hours of daylight is optimal for young snails.
The following is an example of starting H. pomatia in boxes: Build wooden boxes measuring 25 by 35 cm and 25 cm high. Cut a 6 cm-diameter hole (to drain excess moisture) in the bottom and cover the hole with plastic screening, well secured. Cover a frame with plastic screening to create the box lid. The lids either must open or be removable. Keep the boxes on shelves so they are easily accessible. Fill the boxes one-third full with loose, uncompacted garden soil baked to kill all organisms (insects, nematodes, bacteria
, etc.). [Use soil that does not have fertilizer or chemicals in it.] Partially cover the soil with moss, but leave enough room for the snails to crawl around on the dirt. Sprinkle water on the moss.
Move to boxes (three per box) those snails in the outdoor pen that are starting to make holes in which to lay their eggs. After the snails lay eggs, return them to the outside pen. The soil in the boxes must not dry out. Always keep the moss slightly moist. Too much moisture is dangerous, however, as the eggs may swell up and burst. The eggs hatch in about 25 days, but the baby snails remain in the egg "shells." They then work their way out of the nest for about 10 additional days before they appear on the moss and on the sides of the box. Snails on the wood sides of the box are in danger of drying out and must be carefully removed and put on the moss. Shells are very fragile at this time.
Feed the baby snails tender lettuce
leaves (Boston type, but head type is probably just as good.) [This description does not include a water trough, but the authors assume there is one. The snails should have water available.]
Three weeks after the snails appear on the moss, carefully remove the baby snails and put them together in a temporary container. Carefully remove the moss and dirt, watching for any more baby snails. Replace the dirt and moss with fresh (sterilized/baked) dirt and fresh moss. Count and return the snails to the box.
The young snails can be kept over winter in these boxes. Stack the boxes in a cool room protected from frost. The room should never get colder than 0 °C nor warmer than 3 °C (32 °F to 37 °F). Snails will become active again the following spring when the temperature rises above 5 °C (41 °F). Feed them for 4 weeks. They should now average about 8 mm. Move them to a pen, carefully clean and dry the boxes, and prepare the boxes for the new season. H. pomatia matures in 18 months to 4 years.
Mixed system: A variation of the method above is to let the snails lay the eggs in the outdoor pen, then carefully transfer the eggs to the boxes. [The other steps are the same.] In the pen, look for snails that have dug holes and are in them laying eggs. The tip of their shell will be visible. Stick a marker in the ground next to the hole. When the snail is finished and leaves, use a garden trowel to dig up the eggs and move them. This task is difficult. The eggs can be both physically damaged and covered with dirt.
Example: Five stages of snail raising
Some who raise H. aspersa separate the five stages: reproduction, hatching, young, fattening, and final fattening.
In a typical example, the breeding box has concrete
sides, soil with earthworms (to cleanse the soil) on the bottom, vegetation, curved tiles to provide shelter, feeders, and a chicken waterer. Mosquito
netting or screening covers the top. These breeding boxes may be outside, or you may get better results when the boxes are inside a greenhouse—as long as the greenhouse does not get too hot or too dry. One researcher reported that in outdoor boxes, each breeder snail had about seven young. In greenhouses, each breeder snail had about 9 to 12 young. The researcher felt that under better weather conditions than those he had that year, each adult breeder snail would have produced 15 young snails.
Fattening pens may be outside or in a greenhouse. High summer temperatures and insufficient moisture cause dwarfing and malformations of some snails. This is more a problem inside greenhouses if the sun overheats the building. A sprinkler system (e.g., a horticultural system or common lawn sprinklers) can supply moisture. Make sure excess water can drain.
Fattening pens may contain 2 foot (0.6096 m) by 3 foot (0.9144 m) pieces (or other convenient size) of heavy plastic sheets, hung from boards resting on a rack that lets the tips of the plastic sheets just touch the ground. The plastic sheets are about 4 inches apart. The sheets give the snails a resting and hiding place. Feeders may be located on the rack that supports the plastic sheets.
Put a layer of coarse sand and topsoil with earthworms on the fattening pen's bottom. The worms help clean up the snail droppings.
You can put snails that hatched the previous summer in a chilled room for hibernation over winter. Then, about the 1st of April, (adjusted for your local climate), move them to the final fattening pen. If you have several fattening pens, put the smaller snails in one, medium in another, large in another. Do not exceed one-third pound of H. aspersa snails per square foot of pen. Since snails lose weight when they estivate in summer, some growers do not stock pens by weight but by count. For H. aspersa, 10 to 12 snails per square foot is about the maximum.
Breeding pens can be set up just like the fattening pens or the fattening pens can be used as breeding pens after you harvest the mature snails. Harvest some snails and leave some to breed.
also will be low. If hatching extends over a longer period, cannibalism may increase. Some eggs eaten are eggs that were not fertile or did not develop properly, but sometimes, properly developing embryos might be eaten. A high density of "clutches" of egg masses increases the rate of cannibalism, as other nearby egg masses are more likely to be found and eaten. Snail egg has 12 to 20 times the protein of salad. The protein helps the baby snails start developing quickly and be healthier. Snail egg is an excellent starter food for newly hatched snails, but they tend to only eat eggs of their own species.
. Feeding activity depends on the weather, and snails may not necessarily feed every day. Evening irrigation in dry weather may encourage feeding since the moisture makes it easier for the snails to move about.
Put the breeding snails in the breeding pens in April or early May. Feed until mid June when mating begins and the snails stop feeding. Snails resume eating after they lay eggs. Once snails have laid their eggs, you can remove the adult snails. This leaves more food and less crowding for the hatchlings.
Snails of the same species collected from different regions may have different food preferences. Some foods that snails eat are: Alyssum
, fruit and leaves of apple
, apricot
, artichoke
(a favorite), aster, barley
, beans, bindweed
, California boxwood, almost any cabbage
variety, camomile, carnation
, carrot
, cauliflower
, celeriac
(root celery), celery
, ripe cherries, chive, citrus, clover
, cress
, cucumbers (a favorite snail food), dandelion, elder
, henbane
, hibiscus
, hollyhock
, kale
, larkspur
, leek
, lettuce (liked, and makes good snails), lily, magnolia
, mountain ash
, mulberry
, mums, nasturtium
, nettle
, nightshade berries, oats
, onion
greens, pansy
, parsley
, peach
, ripe pear
s, peas
, petunia
, phlox
, plum
, potatoes (raw or cooked), pumpkins, radish
, rape
, rose
, sorrel
, spinach
, sweet pea
, thistle
, thorn apple, tomatoes (well liked), turnip
, wheat
, yarrow
, zinnia
. They will eat sweet lupin
es, but will reject bitter lupin
es and other plants with high quinolizidine
alkaloids. Snails also avoid plants that produce other defensive chemicals, defensive stem hairs, etc.
Snails usually prefer juicy leaves and vegetables over dry ones. If you feed snails vegetable trimmings, damaged fruit, and cooked potatoes, promptly remove uneaten food as it will quickly spoil. You may supply bran that is wet or sprinkle dry bran over leafy vegetables. The diet may consist of 20% wheat bran while 80% is fruit and vegetable material. Some growers use oats
, corn meal, soybean meal
, or chicken
mash. Laying mash provides calcium, as does crushed oyster
shells. Snails also may eat materials such as cardboard (but do not purposely feed it to them); they can eat through shipping cartons and escape. Snails may sometimes eat, within a 24-hour period, food equal to 10%, and occasionally as much as 20%, of their body weight
. Active snails deprived of food will lose more than one-third of their weight before they starve to death—a process that takes 8 to 12 weeks. Estivating snails can survive much longer.
Supply calcium at least once a week if it is not available in the soil. It should not contain harmful salts or be so alkaline as to burn the snails. Mix calcium with wet bran or mashed potatoes and serve on a pan; this will keep any leftover food from rotting on the ground.
Some researchers use chicken mash for feed. You can cut a plastic pipe in half lengthwise to make two troughs which can be used as feeders for mash. Mix laying mash (used for egg-producing hens) into the feed to provide calcium for the snails' shells. Commercial chicken feeding mash is around 16% to 17% protein, from fish meal and meat meal, making it good for growing snails. Supplying mash to hatchlings might reduce cannibalism. Two feeds that snails like and that promote good growth are: (A) broiler finisher mash consisting of 7% broiler concentrate, 58% corn, 16% soya, 18% sorghum, 7 % limestone flour (40% Ca); and (B) chicken feed (pellets) for layers consisting of 5% layer concentrate, 10%, corn, 15% soya, 20% sorghum, 44% barley, 6% limestone flour (40%Ca).
Pellets are fine for larger snails, but mash is better for younger ones. Partially crush pellets if you feed them to young snails. Snails do not grow well if rabbit pellets are their primary diet. Snails show a distinct preference for moist feed. Ensure easy access to enough water if you feed snails dry mash.
Be sure to frequently clean the feed and water dishes. The amount of feed a snail eats depends very much on air humidity and on the availability of drinking water. You can serve clean drinking water in a shallow container to reduce the risk of the snail drowning. Some types of chicken waterers may be suitable. Other factors (e.g., temperature, light intensity, food preferences versus food supplied, etc.) also affect feeding. A compromise, until you find the optimum feed, is to feed half green vegetable material and half chicken feed/grain/animal protein.
Young H. aspersa readily eats milk powder. Its rapid rate of assimilation promotes rapid growth.
Parasites
, nematode
s, trematodes
, fungi, and microarthropod
s can attack snails, and such problems can spread rapidly when snail populations are dense. The bacterium Pseudomonas aeruginosa
causes intestinal infections that can spread rapidly in a crowded snail pen.
Possible predators include rat
s, mice
, moles
, skunk
s, weasel
s, bird
s, frog
s and toad
s, lizard
s, walking insects (e.g., some beetle
and cricket
varieties), some types of flies
, centipede
s, and even certain carnivorous snail species, such as Strangesta capillacea.
Snails tend not to breed when packed too densely or when the slime in the pen accumulates too much. The slime apparently works like a pheromone
and suppresses reproduction. On the other hand, snails in groups of about 100 seem to breed better than when only a few snails are confined together. Perhaps they have more potential mates from which to choose. Snails in a densely populated area grow more slowly even when food is abundant, and they also have a higher mortality rate. These snails then become smaller adults who lay fewer clutches of eggs, have fewer eggs per clutch, and the eggs have a lower hatch rate. Smaller adult snails sell for less. Dwarfing
is quite common in snail farming and is attributable mainly to rearing conditions rather than heredity
factors. Crowding snails is false economy. A recommended rate for H. aspersa is not more than one-third pound per square foot (3.6 kg/m²) of soil surface for snails that weigh more than 1 gram and not more than 0.2 pound per square foot (2.2 kg/m²) for snails that weigh less. (One ounce is about 28 grams.)
The Federal Plant Pest Act defines a plant pest as "any living stage (including active and dormant forms) of insects, mites
, nematodes, slugs, snails, protozoa
, or other invertebrate
animals, bacteria
, fungi, other parasitic plants or reproductive parts thereof; viruses; or any organisms similar to or allied with any of the foregoing; or any infectious
substances, which can directly or indirectly injure or cause disease or damage in or to any plants or parts thereof, or any processed, manufactured, or other products of plants..." The Animal and Plant Health Inspection Service
(APHIS) categorizes giant African snails as a "quarantine significant plant pest." The United States does not allow live giant African snails into the country under any circumstances. It is illegal to own or to possess them. APHIS vigorously enforces this regulation and destroys or returns these snails to their country of origin.
Since large infestations of snails can do devastating damage, many states have quarantines against nursery products, and other products, from infested states. Further, it is illegal to import snails (or slugs) into the U.S. without permission from the Plant Protection and Quarantine Division(PPQ), Animal Plant Health and Inspection Service, U.S. Department of Agriculture. APHIS also oversees interstate transportation of snails. Anyone who plans to "import, release, or make interstate shipments of" snails, must complete APHIS's PPQ Form 526, Application and Permit to Move Live Plant Pests and Noxious Weeds. Submit the form to your State regulatory official. The state will process the request and make a recommendation to APHIS who will then make a decision.
Information on Plant Pest Permits is available at APHIS's web site http://www.aphis.usda.gov/ppq/permits/.
The Food and Drug Administration
(FDA) regulates the canning of low-acid
foods such as snails. According to FDA, "establishments engaged in the manufacture of Low-acid or Acidified Canned Foods (LACF) offered for interstate commerce in the United States are required. . .to register their facility. . .and file scheduled processes for their products with" the FDA. This does not refer to fresh products. For appropriate forms, contact: LACF Registration Coordinator, HFS-618, Food and Drug Administration, Center for Food Safety and Applied Nutrition, 200 C Street, S.W., Washington, D.C. 20204. Telephone: (202) 205-5282. FAX: (202) 205-4758 or (202) 205-4128.
Improper canning of low-acid meats, e.g., snails, involves a risk of botulism
. When canning snails for home consumption, carefully follow canning instructions for low-acid meats to prevent food poisoning.
State laws also may apply to imports into certain states and to raising snails in a given state. Your state also may want to inspect and approve your facility. Thus anyone who plans to raise snails also should check with their State's Agriculture Department.
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
s specifically for human consumption, and more recently, to obtain snail slime
Snail slime
Snail slime is a kind of mucus, an external bodily secretion which is produced by snails, gastropod mollusks. Land snails and slugs produce mucus, but so does every other kind of gastropod, from marine, freshwater and terrestrial habitats...
for cosmetics
Cosmetics
Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...
use.
Perhaps the best known and most often cultivated land snail species in the Western world
Western world
The Western world, also known as the West and the Occident , is a term referring to the countries of Western Europe , the countries of the Americas, as well all countries of Northern and Central Europe, Australia and New Zealand...
is Helix pomatia
Helix pomatia
Helix pomatia, common names the Burgundy snail, Roman snail, edible snail or escargot, is a species of large, edible, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae...
, the Roman snail, Burgundy snail or apple snail. Another species eaten is Helix aspersa
Helix aspersa
Helix aspersa, known by the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs. The species has been placed in the genus Helix, in all sources between 1774 and 1988 and in most sources until recently...
. Both of these land snails are European in their native range.
Other species of land snail that are consumed by humans are found in Europe, Northern Africa, North America and in various other parts of the world.
History
In ancient Rome
Rome
Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...
, snails were fattened up in "cochlear" gardens before they were eaten. The Romans, in particular, are known to have considered escargot as an elite food, as noted in the writings of Pliny
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
. For example the species Otala lactea
Otala lactea
Otala lactea, common names, the milk snail, or Spanish snail, is a large, edible species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae. Archaeological recovery at the Volubilis illustrates prehistoric exploitation of O...
of edible snails has been recovered in archaeological excavation from Volubilis
Volubilis
Volubilis is an archaeological site in Morocco situated near Meknes between Fez and Rabat along the N13 road. The nearest town is Moulay Idriss. Volubilis features the best preserved Roman ruins in this part of northern Africa...
in present day Morocco
Morocco
Morocco , officially the Kingdom of Morocco , is a country located in North Africa. It has a population of more than 32 million and an area of 710,850 km², and also primarily administers the disputed region of the Western Sahara...
. "A Virginia Farmer" described keeping snails in a cool, moist and shady environment, supplying artificial dew if necessary, containing them on an "island" surrounded by water to prevent escape, supplying vegetation as feed, and fattening them on corn meal.
Pliny
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
described the snail garden of Fulvius Hirpinus 2,000 years ago as having separate sections for different species of snails. Hirpinus allegedly fed his snails on meal and wine. But note, stale beer placed in a shallow dish is a way of killing them. Snails are attracted to the yeast in beer and will crawl into the dish and drown.
The Romans selected the best snails for breeding. "Wall fish" were often eaten in Britain, but were never as popular as on the continent. There, people often ate snails during Lent, and in a few places, they consumed large quantities of snails at Mardi Gras or Carnival, as a foretaste of Lent
Lent
In the Christian tradition, Lent is the period of the liturgical year from Ash Wednesday to Easter. The traditional purpose of Lent is the preparation of the believer – through prayer, repentance, almsgiving and self-denial – for the annual commemoration during Holy Week of the Death and...
.
According to some sources, the French imported brown garden snails
Helix aspersa
Helix aspersa, known by the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs. The species has been placed in the genus Helix, in all sources between 1774 and 1988 and in most sources until recently...
to California in the 1850s, raising them as the delicacy escargot. Other sources claim that Italian immigrants were the first to bring the snail to the United States.
Economic impact
U.S. imports of snails were worth more than $4.5 million in 1995 and came from 24 countries. This includes preserved or prepared snails and snails that are live, fresh, chilled, or frozen. Major exporters to the U.S. are FranceFrance
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
, Greece
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
and China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. The U.S. exported live, fresh, chilled, or frozen snails worth $55,000 to 13 countries; most were shipped to Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, the Netherlands, and the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
. Individual statistics are not available for U.S. exports of prepared or processed snails from the U.S. Department of Commerce.
List of edible land snail species
Helix aspersa
Helix aspersa, known by the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs. The species has been placed in the genus Helix, in all sources between 1774 and 1988 and in most sources until recently...
or to Helix pomatia
Helix pomatia
Helix pomatia, common names the Burgundy snail, Roman snail, edible snail or escargot, is a species of large, edible, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae...
, although other varieties of snails are eaten. Achatina fulica, a giant African snail, is sliced and canned
Canning
Canning is a method of preserving food in which the food contents are processed and sealed in an airtight container. Canning provides a typical shelf life ranging from one to five years, although under specific circumstances a freeze-dried canned product, such as canned, dried lentils, can last as...
and passed off on some consumers as escargot. Terms such as "garden snail" or "common brown garden snail" are rather meaningless since they refer to so many types of snails, but they sometimes mean H. aspersa.
- Helix aspersaHelix aspersaHelix aspersa, known by the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs. The species has been placed in the genus Helix, in all sources between 1774 and 1988 and in most sources until recently...
is also known as the French "petit gris," "small grey snail," the "escargot chagrine," or "la zigrinata." The shell of a mature adult has four to five whorls and measures 30 to 45 mm across. It is native to the shores of the Mediterranean and up the coast of Spain and France. It is found on many British Isles, where the Romans introduced it in the 1st century AD (Some references say it dates to the Early Bronze Age.) In the early 19th century the French brought it into California where it has become a serious pest. These snails are now common throughout the U.S. It was introduced into several Eastern and Gulf states even before 1850 and, later introduced into other countries such as South Africa, New Zealand, Mexico, and Argentina. H. aspersa has a life span of 2 to 5 years. This species is more adaptable to different climates and conditions than many snails, and is found in woods, fields, sand dunes, and gardens. This adaptability not only increases H. aspersa's range, but it also makes farming H. aspersa easier and less risky.
- Helix pomatiaHelix pomatiaHelix pomatia, common names the Burgundy snail, Roman snail, edible snail or escargot, is a species of large, edible, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae...
measures about 45 mm across the shell. It also is called the "Roman snail," "apple snail," "lunar," "la vignaiola," the German "Weinbergschnecke," the French "escargot de Bourgogne" or "Burgundy snail," or "gros blanc." Native over a large part of Europe, it lives in wooded mountains and valleys up to 2,000 metres (6,000 ft) altitude and in vineyards and gardens. The Romans may have introduced it into Britain. Immigrants introduced it into the U.S. in Michigan and Wisconsin. Many prefer H. pomatia to H. aspersa for its flavor and its larger size, as the "escargot par excellence."
- Otala lacteaOtala lacteaOtala lactea, common names, the milk snail, or Spanish snail, is a large, edible species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae. Archaeological recovery at the Volubilis illustrates prehistoric exploitation of O...
is sometimes called the "vineyard snail," "milk snail," or "Spanish snail." The shell is white with reddish brown spiral bands and measures about 26 to 35 mm in diameter. Many think it tastes better than H. aspersa.
- Iberus alonensis, the Spanish "vaqueta" or "serrana", measures about 30 mm across the shell.
- Cepaea nemoralis, the "grove snail," or the Spanish "vaqueta", measures about 25 mm across the shell. It inhabits Central Europe and was introduced into, and is now naturalized in many U.S. states, from Massachusetts to California, and from Tennessee to Canada. Its habitat ranges widely from woods to dunes. It mainly eats dead plant material, but it likes nettles and buttercups and will eat dead worms and dead snails.
- Cepaea hortensis, the "white-lipped snail", measures about 20 mm across the shell which often has distinct dark stripes. It is native to central and northern Europe. This species was introduced into Maine, Massachusetts, and New Hampshire in colonial times, but it never became established in these states. Its habitat varies but C. hortensis is found in colder and wetter places than C. nemoralis. Their smaller size and some people's opinion that they do not taste as good make C. hortensis and C. nemoralis less popular thanthe larger European land snails.
- Otala punctataOtala punctataOtala punctata is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae. They are prepared in a typical dish in South Spain, "cabrillas", cooked in spicy tomato sauce.-Distribution:...
, called "vaqueta" in some parts of Spain, measures about 35 mm across the shell.
- Eobania vermiculataEobania vermiculataEobania vermiculata also known as Helix vermiculata, common name the "chocolate-band snail" is a species of large, air-breathing, land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae, the true snails or typical snails....
, the "vinyala," "mongeta," or "xona", measures about 25 mm. It is found in Mediterranean countries and was introduced into Louisiana and Texas.
- Helix lucorumHelix lucorumHelix lucorum is a species of large, edible, air-breathing land snail or escargot, a terrestrial pulmonate gastropod mollusk in the family Helicidae, the typical snails.- Synonyms :Numerous synonyms exist for Helix lucorum:...
, sometimes called "escargo turc," measures about 45 mm across the shell. It is found in central Italy and from Yugoslavia through the Crimea to Turkey and around the Black Sea.
- Helix adanensis comes from around Turkey.
- Helix apertaHelix apertaHelix aperta, also known as Cantareus apertus, and commonly known as the green garden snail, is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae, the typical snails.-Distribution:...
measures about 25 mm. Its meat is highly prized. It is native to France, Italy, and other Mediterranean countries and has become established in California and Louisiana. Sometimes known as the "burrowing snail," it is found above ground only during rainy weather. In hot, dry weather, it burrows three to six inches into the ground and becomes dormant until rain softens the soil.
- Theba pisanaTheba pisanaTheba pisana, common names the white garden snail, the sand hill snail, white Italian snail, the Mediterranean coastal snail, or simply the Mediterranean snail, is an edible species of medium-sized air-breathing land snail, a pulmonate gastropod mollusk in the family Helicidae...
, also called the "banded snail"or the "cargol avellanenc", measures about 20 mm and lives on dry, exposed sites, usually near the sea. Native to Sicily, it has been spread to several European countries, including England. This snail is a serious garden pest and is the "white snail" that California once eradicated by using flamethrowers to burn off whole areas. In large numbers, up to 3,000 snails per tree, it can ravage a garden in 24 hours and a citrus or other crop in a couple of nights.
- Sphincterochila candidissimaSphincterochila candidissimaSphincterochila candidissima is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Sphincterochilidae.- Subspecies :* Sphincterochila candidissima crassa -Distribution :...
or Leucochroa candidisima, the "cargol mongeta," or "cargol jueu" measures about 20 mm.
- Achatina fulica and other Achatina species, giant African snails. They can grow up to 326 mm (1 ft ¾ in) in length. Their native range is south of the Sahara in East Africa. This snail was purposely introduced into India in 1847. There was an unsuccessful attempt to establish it in Japan in 1925. It has been purposely and accidentally transported to other Pacific locations and was inadvertently released in California after World War II, in Hawaii, and later in North Miami Florida in the 1970s. In many places, it is a serious agricultural pest that causes considerable crop damage. Also, due to its large size, its slime and fecal material create a nuisance as does the odor that occurs when something like poison bait causes large numbers to die. The U.S. has made considerable effort to eradicate Achatina. The U.S. Department of Agriculture (USDA) has banned the importation and possession of live Giant African snails. However, they are still sought after as pets due to the vibrant "tiger stripes" on their shells.
General
Snails are hermaphroditeHermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
s. Although they have both male and female reproductive organs, they must mate with another snail of the same species before they lay eggs. Some snails may act as males one season and as females the next. Other snails play both roles at once and fertilize each other simultaneously. When the snail is large enough and mature enough, which may take several years, mating occurs in the late spring or early summer after several hours of courtship
Courtship
Courtship is the period in a couple's relationship which precedes their engagement and marriage, or establishment of an agreed relationship of a more enduring kind. In courtship, a couple get to know each other and decide if there will be an engagement or other such agreement...
. Sometimes there is a second mating in summer. (In tropical climates, mating may occur several times a year. In some climates, snails mate around October and may mate a second time 2 weeks later.) After mating, the snail can store sperm received for up to a year, but it usually lays eggs within a few weeks. Snails are sometimes uninterested in mating with another snail of the same species that originated from a considerable distance away. For example, a H. aspersa from southern France may reject a H. aspersa from northern France.
Helix pomatia
Snails need soil at least 2 inches deep in which to lay their eggs. For H. pomatia, the soil should be at least 3 inches deep. Keep out pests such as ants, earwigEarwig
Earwigs make up the insect order Dermaptera, found throughout the Americas, Africa, Eurasia, Australia and New Zealand. With 1,800 species in 12 families, they are one of the smaller insect orders...
s, millipede
Millipede
Millipedes are arthropods that have two pairs of legs per segment . Each segment that has two pairs of legs is a result of two single segments fused together as one...
s, etc. Dry soil is not suitable for the preparation of a nest, nor is soil that is too heavy. In clay soil that becomes hard, reproduction rates may decrease because the snails are unable to bury their eggs and the hatchlings have difficulty emerging from the nest. Hatchability of eggs depends on soil temperature, soil humidity, soil composition, etc. Soil consisting of 20% to 40% organic material is good. Keep the soil 65 °F to 80 °F (18 °C to 27 °C), best around 70 °F (21 °C). Maintain soil moisture of 80%. One researcher removes eggs immediately after they are deposited, counts them, then keeps them on moist cotton until the eggs hatch and the young start to eat. Snails lose substantial weight by laying eggs. Some do not recover. About one-third of the snails will die after the breeding season.
H. pomatia eggs measure about 3 mm in diameter and have a calcareous
Calcareous
Calcareous is an adjective meaning mostly or partly composed of calcium carbonate, in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines.-In zoology:...
shell and a high yolk content. H. pomatia lays the eggs in July or August, 2 to 8 weeks after mating, in holes dug out in the ground. (Data varies widely on how long after mating snails lay eggs.) The snail puts its head into the hole or may crawl in until only the top of the shell is visible; then it deposits eggs from the genital opening just behind the head. It takes the snail 1 to 2 days to lay 30 to 50 eggs. Occasionally, the snail will lay about a dozen more a few weeks later. The snail covers the hole with a mixture of the slime it excretes and dirt. This slime, which the snail excretes to help it crawl and to help preserve the moisture in its soft body, is glycoprotein
Glycoprotein
Glycoproteins are proteins that contain oligosaccharide chains covalently attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. In proteins that have segments extending...
similar to eggwhite.
Fully developed baby H. pomatia snails hatch about 3 to 4 weeks after the eggs are laid, depending on temperature and humidity. Birds, insects, mice, toads and other predators take a heavy toll on the young snails. The snails eat and grow until the weather turns cold. They then dig a deep hole, sometimes as deep as 1 foot (0.3048 m), and seal themselves inside their shell and hibernate for the winter. This is a response to both decreasing temperature and shorter hours of daylight. When the ground warms up in spring, the snail emerges and goes on a binge of replacing lost moisture and eating.
Helix aspersa
H. aspersa eggs are white, spherical, about 3 mm in diameter and are laid 5 days to 3 weeks after mating. (Data varies widely due to differences in climate and regional variations in the snails' habitats.) H. aspersa lays an average of 85 eggs in a nest that is 1 to 1½ inches deep. Data varies from 30 to over 120 eggs, but high figures may be from when more than one snail lays eggs in the same nest.In warm, damp climates, H. aspersa may lay eggs as often as five times from February through October, depending on the weather and region. Mating and egg-laying begin when there are at least 10 hours of daylight and continue until days begin to get shorter. In the United States, longer hours of sunlight that occur when temperatures are still too cold will affect this schedule, but increasing hours of daylight still stimulate egg laying. If warm enough, the eggs hatch in about 2 weeks, or in 4 weeks if cooler. It takes the baby snails several more days to break out of the sealed nest and climb to the surface. In a climate similar to southern California's, H. aspersa matures in about 2 years. In central Italy, H. aspersa hatches and emerges from the soil almost exclusively in the autumn. If well fed and not overcrowded, those snails that hatch at the start of the season will reach adult size and form a lip at the edge of their shell by the following June. If you manipulate the environment to get more early hatchlings, the size and number of snails that mature the following year will increase. In South Africa, some H. aspersa mature in 10 months, and under ideal conditions in a laboratory, some have matured in 6 to 8 months. Most of H. aspersa's reproductive activity takes place in the second year of its life.
Achatina fulica
By contrast, one giant African snail, Achatina fulica, lays 100 to 400 elliptical eggs that each measure about 5 mm long. Each snail may lay several batches of eggs each year, usually in the wet season. They may lay eggs in holes in the ground like H. pomatia, or lay eggs on the surface of a rocky soil, in organic matter, or at the base of plants. In 10 to 30 days, the eggs hatch releasing snails about 4 mm long. These snails grow up to 10 mm per month. After 6 months, the Achatina fulica is about 35 mm long and may already be sexually mature. Sexual maturitySexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
takes 6 to 16 months, depending on weather and the availability of calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
. This snail lives 5 or 6 years, sometimes as many as 9 years.
Growth
Within the same snail population and under the same conditions, some snails will grow faster than others. Some will take twice as long to mature. This may help the species survive bad weather, etc., in the wild. However, a snail farmer should obviously select and keep the largest and fastest maturing snails for breeding stock and sell the smaller snails. By selecting only the largest, the average size of the snail may increase significantly in only a couple of generations. Most of the differences in growth are probably due to environmental factors including stocking density. However, to whatever extent these differences are genetic, you might as well breed large, fast-growing snails instead of small, slower-growing ones.Several factors can greatly influence the growth of snails including: population density; stress [snails are sensitive to noise, light, vibration, unsanitary conditions, irregular feedings, being touched, etc.]; feed; temperature and moisture; and the breeding technology used.
H. aspersa requires at least 3% to 4% calcium in the soil (or another source of calcium) for good growth. Most snails need more calcium in the soil than H. aspersa. Low calcium intake will slow the growth rate and cause the shell to be thinner. Calcium may be set out in a feeding dish or trough so the snails can eat it at will. Food is only one calcium source. Snails may eat paint or attack walls of buildings seeking calcium, and they also will eat dirt.
A newborn's shell size depends on the egg size since the shell develops from the egg's surface membrane. As the snail grows, the shell is added onto in increments. Eventually the shell will develop a flare or reinforcing lip at its opening. This shows that the snail is now mature; there will be no further shell growth. Growth is measured by shell size, since a snail's body weight varies and fluctuates, even in 100% humidity. The growth rate varies considerably between individuals in each population group. Adult size, which is related to the growth rate, also varies, thus the fastest growers are usually the largest snails. Eggs from larger, healthier snails also tend to grow faster and thus larger.
Dryness inhibits growth and even stops activity. When it becomes too hot and dry in summer, the snail becomes inactive, seals its shell and estivates
Estivation
Aestivation is a state of animal dormancy, characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions...
(becomes dormant) until cooler, moister weather returns. Some snails estivate in groups on tree trunks, posts, or walls. They seal themselves to the surface thus sealing up the shell opening.
Peak snail activity (including feeding and thus growth) occurs a few hours after sunset, when the temperature is lower and the water content (in the form of dew
Dew
[Image:Dew on a flower.jpg|right|220px|thumb|Some dew on an iris in Sequoia National Park]]Dew is water in the form of droplets that appears on thin, exposed objects in the morning or evening...
) is higher. During daytime snails usually seek shelter.
Farming snails
Successful snail culture requires the correct equipment and supplies, including: snail pens or enclosures; devices for measuring humidity (hygrometerHygrometer
A hygrometer is an instrument used for measuring the moisture content in the environmental air, or humidity. Most measurement devices usually rely on measurements of some other quantity such as temperature, pressure, mass or a mechanical or electrical change in a substance as moisture is absorbed...
), temperature (thermometer
Thermometer
Developed during the 16th and 17th centuries, a thermometer is a device that measures temperature or temperature gradient using a variety of different principles. A thermometer has two important elements: the temperature sensor Developed during the 16th and 17th centuries, a thermometer (from the...
), soil moisture, and light (in foot candles); a weight scale and an instrument to measure snail size; a kit for testing soil contents; and a magnifying glass to see the eggs. You also may need equipment to control the climate (temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
and humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
), to regulate water (e.g., a sprinkler system to keep the snails moist and a drainage system), to provide light and shade, and to kill or keep out pests and predators. Some horticultural systems such as artificial lighting systems and water sprinklers may be adapted for snail culture. You will have better results if you use snails of the same kind and generation. Some recommend putting the hatchlings in another pen.
Four systems of snail farms can be distinguished:
- Outdoor Pens.
- In buildings with a controlled climate.
- In closed systems such as plastic tunnel houses or "greenhouses."
- In addition, snails may breed and hatch inside in a controlled environment and then (after 6 to 8 weeks) may be placed in outside pens to mature.
Favorable conditions
Climate: A mild climate (59-75 F) with high humidity (75% to 95%) is best for snail farming, though most varieties can stand a wider range of temperatures. The optimal temperature is 70 F for many varieties. When the temperature falls below 45 F, snails hibernate. Under 54 F the snails are inactive, and under 50 F, all growth stops. When the temperature rises much above 80 F or conditions become too dry, snails estivate. Wind is bad for snails because it speeds up moisture loss, and snails must retain moisture.Moisture: Snails thrive in damp but not waterlogged environments and thus a well-draining soil is required. Research indicates that water content around 80% of the carrying capacity of the soil and air humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
over 80% (during darkness) are the most favorable conditions. Many farmers use mist-producing devices
Aerosol spray
Aerosol spray is a type of dispensing system which creates an aerosol mist of liquid particles. This is used with a can or bottle that contains a liquid under pressure. When the container's valve is opened, the liquid is forced out of a small hole and emerges as an aerosol or mist...
to maintain proper moisture in the air and/or soil.. Also, if the system contains alive vegetation, the leaves are to be periodically wet.
Soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
: Snails dig in soil and ingest it. Good soil favors snail growth and provides some of their nutrition. Lack of access to good soil may cause fragile shells even when the snails have well-balanced feed; the snails growth may lag far behind the growth of other snails on good soil. Snails will often eat feed, then go eat dirt. Sometimes, they will eat only one or the other.
A well-functional soil would have the following characteristics:
- Containing neither a lot of sandSandSand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
nor too much clayClayClay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
, as snails strive to dig into hard clay and sand dries out easily. - 20%-40% organic matter content. Organic matter enhances cation exchange capacityCation exchange capacityIn soil science, cation-exchange capacity is the maximum quantity of total cations, of any class, that a soil is capable of holding, at a given pH value, for exchanging with the soil solution. CEC is used as a measure of fertility, nutrient retention capacity, and the capacity to protect...
of calcium and magnesiumMagnesiumMagnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...
which in turn stimulates growth. - pHPHIn chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
around 7. - Adequate calciumCalciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
, the primary constituent of shells (up to 98%). A common way to introduce calcium is to add ground limestoneLimestoneLimestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
at a suggested concentration of 4.5 kg per 100 square feet (9.3 m²). Calcium may also be set out in a feeding dish or trough so the snails can eat it at will. More advanced techniques involve the addition of polyacrylamidePolyacrylamidePolyacrylamide is a polymer formed from acrylamide subunits. It can be synthesized as a simple linear-chain structure or cross-linked, typically using N,N-methylenebisacrylamide. Polyacrylamide is not toxic...
with the following concentration: 12.5 cm³ of a 160 g M.A./one preparation in 250 cc of water per kilogram of dry soil. Such stabilization treatment helps the soil structure resist washing and allows regular cleaning without destroying the crumb structure of the soil that is beneficial for egg laying.
Soil care: A farmer must find a way to prevent the soil from becoming fouled with mucus and droppings and also tackle undesirable chemical changes
Soil chemistry
Soil chemistry is the study of the chemical characteristics of soil. Soil chemistry is affected by mineral composition, organic matter and environmental factors.-History:...
that may occur in time.
Soil mix suggestions:
- peatPeatPeat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...
, clay, compostCompostCompost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost is a key ingredient in organic farming. At its most essential, the process of composting requires simply piling up waste outdoors and waiting for the materials to break down from anywhere...
and CaCO3Calcium carbonateCalcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,... - Leaf moldLeaf moldLeaf mold is a form of compost produced by the fungal breakdown of shrub and tree leaves, which are generally too dry, acidic, or low in nitrogen for bacterial decomposition.-Description:...
(at pH 7)
Pens and enclosures
The U.S. Animal and Plant Health Inspection ServiceAnimal and Plant Health Inspection Service
Animal and Plant Health Inspection Service is an agency of the United States Department of Agriculture responsible for protecting animal health, animal welfare, and plant health. APHIS is the lead agency for collaboration with other agencies to protect U.S. agriculture from invasive pests and...
(APHIS
Aphis
Aphis may refer to:* Aphis, a genus of aphid species* Animal and Plant Health Inspection Service , organizational unit of the USDA* HMS Aphis , Royal Navy insect class gunboat...
) Standards for Snail-Rearing Facilities were revised March 2001 and are available at http://www.aphis.usda.gov:80/ppq/permits/plantpest/rearing.pdf
Enclosures for snails are usually long and thin instead of square. This allows you to walk around (without harming the snails) and reach in the whole pen. The enclosure may be a trough with sides made of wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
, block, fiber cement sheets, or galvanized sheet steel. Cover it with screen
Sieve
A sieve, or sifter, separates wanted elements from unwanted material using a woven screen such as a mesh or net. However, in cooking, especially with flour, a sifter is used to aerate the substance, among other things. A strainer is a type of sieve typically used to separate a solid from a liquid...
or netting
Netting
In general, netting means to allow a positive value and a negative value to set-off and partially or entirely cancel each other out.In the context of credit risk, there are at least three specific types of netting:...
. The covering will confine the snails and keep out birds and other predators. Fences or walls are usually 2 foot (0.6096 m) high plus at least 5 inches into the ground. Fencing made of galvanized metal or hard-plastic sheets helps keep out some predators. A cover will protect against heavy rain. Shade (which may be a fine mesh screen) on warm winter days helps keep the snails dormant. Use 5 mm mesh or finer for pen screens or fences. Pens containing baby snails will need a finer mesh.
Snails like hiding places, especially during the warm daytime. For example, purchase plastic soil drainage pipes from the local garden center, split them in two lengthwise, and stack one layer one way and the next layer at a right angle. This will provide shelter and will increase by 50% the number of snails you can put in the pen.
A sprinkler system will ensure moisture when needed. Turn it on at sunset. If turned on early in the day, the moisture may drive snails out into hot sunshine. Monitor temperature and humidity using a thermometer and a hygrometer.
Although you can use fencing for the enclosure's sides, the bottom, if not the ground or trays of dirt, must be a surface more solid than screening. A snail placed in a wire-mesh-bottom pen will keep crawling, trying to get off the wires and onto solid, more comfortable ground.
Preventing escapes: In an open pen, curve the top of the fences inward in a half circle to confine the vineyard snail. H. aspersa will escape from such an open pen, so you could use an electric fence to contain them. [The electric fence
Electric fence
An electric fence is a barrier that uses electric shocks to deter animals or people from crossing a boundary. The voltage of the shock may have effects ranging from uncomfortable, to painful or even lethal...
top has two or more thin wires that are 2 to 4 mm apart. Each wire carries the opposite charge of the wire next to it. Use a battery or transformer to supply 4 to 12 volt
Volt
The volt is the SI derived unit for electric potential, electric potential difference, and electromotive force. The volt is named in honor of the Italian physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery.- Definition :A single volt is defined as the...
s to the wire. A snail will get a mild shock and retract when it crawls over a wire and touches a second wire.]
Another technique to confine snails is to bend the fence top inward into a sharp "V" shape with about a 20 degree angle. The snail's shell will hit the bent-back part of the screen before he can reach up and start crawling on it. This blocks him, and the angled screen automatically compensates for the size of the snail.
Another alternative, especially handy for solid wall enclosures, is to attach to the wall a horizontal piece of screen that projects inward several inches over the enclosure. Make the screen with material like nylon monofilament that is moderately stiff and springy yet easily flexible. On the inside edge of the screen, remove the cross fibers until you've created a fringe several inches wide. As the would-be escapee crawls on the underside of the screen and moves out onto the fringe, his weight pulls several individual fibers down. One by one, another fiber gets away from the snail and springs back up out of reach. Eventually the snail is dangling by a thread. He then falls because the surface area is not big enough to crawl on.
Since snails usually will not cross a copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
band, another solution is to top the fence with 3-inch-wide (or wider) copper band. You could bend the band so that part of it faces inward and is parallel to the pen floor. If the band is placed too close to the ground, rain may wash soil against the copper and leave a residue that may enable the snail to cross it. Also, be sure to bury the bottom of the fence deep enough into the ground so that the snails don't dig under it.
Pens with gardens: An alternate method is to make a square pen with a 10 feet (3 m)-square garden in it. Plant about six crops, e.g., nettles and artichokes, inside the pen. The snails choose what they want to eat. If it has not rained, turn sprinklers on for about 15 minutes at dusk, unless the snails are dormant. A disadvantage to this method is that, if the snails are not mature at the end of the year, it is difficult to replant fresh plant crops in the pens.
Plastic tunnels make cheap, easy snail enclosures, but it is difficult to regulate heat and humidity. The tunnel will be 10 to 20 warmer than the outside, and snails become dormant as the temperature climbs above 80 °F (27 °C.
Indoor pens: With snails raised indoors under controlled conditions, reproduction varies according to the geographic origin of the breeding stock. For example, one researcher found that H. aspersa snails from Brittany
Brittany
Brittany is a cultural and administrative region in the north-west of France. Previously a kingdom and then a duchy, Brittany was united to the Kingdom of France in 1532 as a province. Brittany has also been referred to as Less, Lesser or Little Britain...
seem to do better indoors than snails from another region. To breed snails indoors, keep the temperature at 70 °F and the relative humidity at 80% to 90%; some sources say 95%. Another source recommends 75% humidity by day and 95% at night. The Center for Heliciculture once recommended 65-75% humidity during the day and 85-95% at night at 68 F. In any event, avoid humidity higher than 95% (some say 90%) for any length of time. Excessive humidity can kill snails. Optimum temperature and relative humidity depend on several things, including the snail variety and even where breeding stock was gathered. For H. aspersa, the optimum temperature for hatching eggs seems to be 68 °F (20 °C)at 100% relative humidity. The second best temperature/humidity combination depends on where the snails came from and results can drop drastically to 0% hatching at 17 °C (63 °F) and 100% humidity. Err on the side of a few degrees warmer or a small percentage dryer. Do not keep the soil wet when the humidity is maintained at 100%, as the eggs will absorb water, swell up, and burst.
Use fluorescent lights to give artificial daylight. Different snails respond differently to day length. The ratio of light to darkness influences activity, feeding, and mating andegg-laying. Eighteen or more hours of light apparently stimulate H. aspersa growth, while less than 12 hours inhibit it. Some snail species may associates the long hours of light with the start of summer—the peak growing season. Eighteen hours of daylight also appear optimal for breeding (mating and egg laying), but snails will breed in darkness.
Breeding boxes and cages: Snails can be bred in boxes or cages stacked several units high. Use an automatic sprinkler system to provide moisture. Breeding cages should have a feed trough and a water trough. Plastic trays that are a couple of inches deep are adequate; deeper water troughs increase the chance of snails drowning in them. These trays may be set on a bed of small gravel. Fill small plastic pots, e.g., flower pots about 3 inches deep, with sterilized dirt (or a loamy pH neutral soil) and set them in the gravel to give the snails a place to lay their eggs. Remove and replace each pot after the snails lay eggs. (Set one pot inside another so that you can easily lift one out without shifting the gravel.)
After the snails have laid their eggs, put the pots in a nursery where the eggs will hatch. Keep the young snails in the nursery for about 6 weeks. Then move them to a separate pen as young snails do best if kept with other snails of similar size. Eight hours of daylight is optimal for young snails.
The following is an example of starting H. pomatia in boxes: Build wooden boxes measuring 25 by 35 cm and 25 cm high. Cut a 6 cm-diameter hole (to drain excess moisture) in the bottom and cover the hole with plastic screening, well secured. Cover a frame with plastic screening to create the box lid. The lids either must open or be removable. Keep the boxes on shelves so they are easily accessible. Fill the boxes one-third full with loose, uncompacted garden soil baked to kill all organisms (insects, nematodes, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, etc.). [Use soil that does not have fertilizer or chemicals in it.] Partially cover the soil with moss, but leave enough room for the snails to crawl around on the dirt. Sprinkle water on the moss.
Move to boxes (three per box) those snails in the outdoor pen that are starting to make holes in which to lay their eggs. After the snails lay eggs, return them to the outside pen. The soil in the boxes must not dry out. Always keep the moss slightly moist. Too much moisture is dangerous, however, as the eggs may swell up and burst. The eggs hatch in about 25 days, but the baby snails remain in the egg "shells." They then work their way out of the nest for about 10 additional days before they appear on the moss and on the sides of the box. Snails on the wood sides of the box are in danger of drying out and must be carefully removed and put on the moss. Shells are very fragile at this time.
Feed the baby snails tender lettuce
Lettuce
Lettuce is a temperate annual or biennial plant of the daisy family Asteraceae. It is most often grown as a leaf vegetable. It is eaten either raw, notably in salads, sandwiches, hamburgers, tacos, and many other dishes, or cooked, as in Chinese cuisine in which the stem becomes just as important...
leaves (Boston type, but head type is probably just as good.) [This description does not include a water trough, but the authors assume there is one. The snails should have water available.]
Three weeks after the snails appear on the moss, carefully remove the baby snails and put them together in a temporary container. Carefully remove the moss and dirt, watching for any more baby snails. Replace the dirt and moss with fresh (sterilized/baked) dirt and fresh moss. Count and return the snails to the box.
The young snails can be kept over winter in these boxes. Stack the boxes in a cool room protected from frost. The room should never get colder than 0 °C nor warmer than 3 °C (32 °F to 37 °F). Snails will become active again the following spring when the temperature rises above 5 °C (41 °F). Feed them for 4 weeks. They should now average about 8 mm. Move them to a pen, carefully clean and dry the boxes, and prepare the boxes for the new season. H. pomatia matures in 18 months to 4 years.
Mixed system: A variation of the method above is to let the snails lay the eggs in the outdoor pen, then carefully transfer the eggs to the boxes. [The other steps are the same.] In the pen, look for snails that have dug holes and are in them laying eggs. The tip of their shell will be visible. Stick a marker in the ground next to the hole. When the snail is finished and leaves, use a garden trowel to dig up the eggs and move them. This task is difficult. The eggs can be both physically damaged and covered with dirt.
Example: Five stages of snail raising
Some who raise H. aspersa separate the five stages: reproduction, hatching, young, fattening, and final fattening.
In a typical example, the breeding box has concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
sides, soil with earthworms (to cleanse the soil) on the bottom, vegetation, curved tiles to provide shelter, feeders, and a chicken waterer. Mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
netting or screening covers the top. These breeding boxes may be outside, or you may get better results when the boxes are inside a greenhouse—as long as the greenhouse does not get too hot or too dry. One researcher reported that in outdoor boxes, each breeder snail had about seven young. In greenhouses, each breeder snail had about 9 to 12 young. The researcher felt that under better weather conditions than those he had that year, each adult breeder snail would have produced 15 young snails.
Fattening pens may be outside or in a greenhouse. High summer temperatures and insufficient moisture cause dwarfing and malformations of some snails. This is more a problem inside greenhouses if the sun overheats the building. A sprinkler system (e.g., a horticultural system or common lawn sprinklers) can supply moisture. Make sure excess water can drain.
Fattening pens may contain 2 foot (0.6096 m) by 3 foot (0.9144 m) pieces (or other convenient size) of heavy plastic sheets, hung from boards resting on a rack that lets the tips of the plastic sheets just touch the ground. The plastic sheets are about 4 inches apart. The sheets give the snails a resting and hiding place. Feeders may be located on the rack that supports the plastic sheets.
Put a layer of coarse sand and topsoil with earthworms on the fattening pen's bottom. The worms help clean up the snail droppings.
You can put snails that hatched the previous summer in a chilled room for hibernation over winter. Then, about the 1st of April, (adjusted for your local climate), move them to the final fattening pen. If you have several fattening pens, put the smaller snails in one, medium in another, large in another. Do not exceed one-third pound of H. aspersa snails per square foot of pen. Since snails lose weight when they estivate in summer, some growers do not stock pens by weight but by count. For H. aspersa, 10 to 12 snails per square foot is about the maximum.
Breeding pens can be set up just like the fattening pens or the fattening pens can be used as breeding pens after you harvest the mature snails. Harvest some snails and leave some to breed.
Cannibalism by hatchlings
The first snails to hatch eat the shells of their eggs. This gives them calcium needed for their shells. They may then begin eating unhatched eggs. If the snail eggs are kept at the optimum temperature, 68 F (for some varieties), and if none of the eggs lose moisture, most eggs will hatch within 1 to 3 days of each other. CannibalismCannibalism
Cannibalism is the act or practice of humans eating the flesh of other human beings. It is also called anthropophagy...
also will be low. If hatching extends over a longer period, cannibalism may increase. Some eggs eaten are eggs that were not fertile or did not develop properly, but sometimes, properly developing embryos might be eaten. A high density of "clutches" of egg masses increases the rate of cannibalism, as other nearby egg masses are more likely to be found and eaten. Snail egg has 12 to 20 times the protein of salad. The protein helps the baby snails start developing quickly and be healthier. Snail egg is an excellent starter food for newly hatched snails, but they tend to only eat eggs of their own species.
Feeding
Feeding season is April through October, (or may vary with the local climate), with a "rest period" during the summer. Do not place food in one small clump so that there is not enough room for all the snails to get to it. Snails eat solid food by rasping it away with their radulaRadula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
. Feeding activity depends on the weather, and snails may not necessarily feed every day. Evening irrigation in dry weather may encourage feeding since the moisture makes it easier for the snails to move about.
Put the breeding snails in the breeding pens in April or early May. Feed until mid June when mating begins and the snails stop feeding. Snails resume eating after they lay eggs. Once snails have laid their eggs, you can remove the adult snails. This leaves more food and less crowding for the hatchlings.
Snails of the same species collected from different regions may have different food preferences. Some foods that snails eat are: Alyssum
Alyssum
Alyssum is a genus of about 100–170 species of flowering plants in the family Brassicaceae, native to Europe, Asia, and northern Africa, with the highest species diversity in the Mediterranean region...
, fruit and leaves of apple
Apple
The apple is the pomaceous fruit of the apple tree, species Malus domestica in the rose family . It is one of the most widely cultivated tree fruits, and the most widely known of the many members of genus Malus that are used by humans. Apple grow on small, deciduous trees that blossom in the spring...
, apricot
Apricot
The apricot, Prunus armeniaca, is a species of Prunus, classified with the plum in the subgenus Prunus. The native range is somewhat uncertain due to its extensive prehistoric cultivation.- Description :...
, artichoke
Artichoke
-Plants:* Globe artichoke, a partially edible perennial thistle originating in southern Europe around the Mediterranean* Jerusalem artichoke, a species of sunflower with an edible tuber...
(a favorite), aster, barley
Barley
Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...
, beans, bindweed
Bindweed
Bindweed may refer to:* Convolvulaceae , a family including about 60 genera and more than 1,650 species** Calystegia , a genus of about 25 species of flowering plants...
, California boxwood, almost any cabbage
Cabbage
Cabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
variety, camomile, carnation
Carnation
Dianthus caryophyllus is a species of Dianthus. It is probably native to the Mediterranean region but its exact range is unknown due to extensive cultivation for the last 2,000 years. It is the wild ancestor of the garden carnation.It is a herbaceous perennial plant growing to 80 cm tall...
, carrot
Carrot
The carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh...
, cauliflower
Cauliflower
Cauliflower is one of several vegetables in the species Brassica oleracea, in the family Brassicaceae. It is an annual plant that reproduces by seed...
, celeriac
Celeriac
Celeriac is also known as celery root, turnip-rooted celery or knob celery. It is a kind of celery, grown as a root vegetable primarily for its large and bulbous hypocotyl rather than for its stem and leaves. The swollen hypocotyl is typically used when it is about 10–12 cm in...
(root celery), celery
Celery
Apium graveolens is a plant species in the family Apiaceae commonly known as celery or celeriac , depending on whether the petioles or roots are eaten: celery refers to the former and celeriac to the latter. Apium graveolens grows to 1 m tall...
, ripe cherries, chive, citrus, clover
Clover
Clover , or trefoil, is a genus of about 300 species of plants in the leguminous pea family Fabaceae. The genus has a cosmopolitan distribution; the highest diversity is found in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes...
, cress
Cress
-Plants:* Alpine Rock Cress* Bulbous Cress* Cedar Glade Cress* Garden cress, a leafy vegetable* Hoary Bitter Cress* Hoary Cress* Indian Cress* Land cress, a biennial herb* Marsh Cress* Peppercress, a mustard* Rockcress, several brassicales...
, cucumbers (a favorite snail food), dandelion, elder
Elderberry
Sambucus is a genus of between 5 and 30 species of shrubs or small trees in the moschatel family, Adoxaceae. It was formerly placed in the honeysuckle family, Caprifoliaceae, but was reclassified due to genetic evidence...
, henbane
Henbane
Henbane , also known as stinking nightshade or black henbane, is a plant of the family Solanaceae that originated in Eurasia, though it is now globally distributed.-Toxicity and historical usage:...
, hibiscus
Hibiscus
Hibiscus is a genus of flowering plants in the mallow family, Malvaceae. It is quite large, containing several hundred species that are native to warm-temperate, subtropical and tropical regions throughout the world...
, hollyhock
Hollyhock
Alcea , commonly known as hollyhocks, is a genus of about 60 species of flowering plants in the mallow family Malvaceae. Most species are native to southwest and central Asia, although a few are native to southeast Europe or Egypt...
, kale
Kale
Kale is very high in beta carotene, vitamin K, vitamin C, lutein, zeaxanthin, and reasonably rich in calcium. Kale, as with broccoli and other brassicas, contains sulforaphane , a chemical with potent anti-cancer properties. Boiling decreases the level of sulforaphane; however, steaming,...
, larkspur
Larkspur
Larkspur may refer to:* Larkspur, California* Larkspur, Colorado* Larkspur radio system, used by the British Army* Delphinium, a genus of 300 flowers with widespread nativity* Consolida, a genus of 40 flowers native to central and western Eurasia...
, leek
Leek
The leek, Allium ampeloprasum var. porrum , also sometimes known as Allium porrum, is a vegetable which belongs, along with the onion and garlic, to family Amaryllidaceae, subfamily Allioideae...
, lettuce (liked, and makes good snails), lily, magnolia
Magnolia
Magnolia is a large genus of about 210 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae. It is named after French botanist Pierre Magnol....
, mountain ash
Mountain Ash
Mountain Ash is a name used for several trees, none of immediate relation. It may refer to:* Eucalyptus regnans, the tallest of all flowering plants and other floral species* Fraxinus texensis, an ash tree species in Texas...
, mulberry
Mulberry
Morus is a genus of flowering plants in the family Moraceae. The 10–16 species of deciduous trees it contains are commonly known as Mulberries....
, mums, nasturtium
Nasturtium
Tropaeolum , commonly known as Nasturtium literally "nose-twister" or "nose-tweaker"), is a genus of roughly 80 species of annual and perennial herbaceous flowering plants and the only genus in the family Tropaeolaceae...
, nettle
Nettle
Nettles constitute between 24 and 39 species of flowering plants of the genus Urtica in the family Urticaceae, with a cosmopolitan though mainly temperate distribution. They are mostly herbaceous perennial plants, but some are annual and a few are shrubby...
, nightshade berries, oats
OATS
OATS - Open Source Assistive Technology Software - is a source code repository or "forge" for assistive technology software. It was launched in 2006 with the goal to provide a one-stop “shop” for end users, clinicians and open-source developers to promote and develop open source assistive...
, onion
Onion
The onion , also known as the bulb onion, common onion and garden onion, is the most widely cultivated species of the genus Allium. The genus Allium also contains a number of other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion The onion...
greens, pansy
Pansy
The Pansy is a large group of hybrid plants cultivated as garden flowers. Pansies are derived from Viola species Viola tricolor hybridized with other viola species, these hybrids are referred to as Viola × wittrockiana or less commonly Viola tricolor hortensis...
, parsley
Parsley
Parsley is a species of Petroselinum in the family Apiaceae, native to the central Mediterranean region , naturalized elsewhere in Europe, and widely cultivated as an herb, a spice and a vegetable.- Description :Garden parsley is a bright green hairless biennial herbaceous plant in temperate...
, peach
Peach
The peach tree is a deciduous tree growing to tall and 6 in. in diameter, belonging to the subfamily Prunoideae of the family Rosaceae. It bears an edible juicy fruit called a peach...
, ripe pear
Pear
The pear is any of several tree species of genus Pyrus and also the name of the pomaceous fruit of these trees. Several species of pear are valued by humans for their edible fruit, but the fruit of other species is small, hard, and astringent....
s, peas
PEAS
P.E.A.S. is an acronym in artificial intelligence that stands for Performance, Environment, Actuators, Sensors.-Performance:Performance is a function that measures the quality of the actions the agent did....
, petunia
Petunia
Petunia is a widely cultivated genus of flowering plants of South American origin, closely related with tobacco, cape gooseberries, tomatoes, deadly nightshades, potatoes and chili peppers; in the family Solanaceae. The popular flower derived its name from French, which took the word petun, meaning...
, phlox
Phlox
Phlox is a genus of 67 species of perennial and annual plants found mostly in North America in diverse habitats from alpine tundra to open woodland and prairie. Some flower in spring, others in summer and autumn....
, plum
Plum
A plum or gage is a stone fruit tree in the genus Prunus, subgenus Prunus. The subgenus is distinguished from other subgenera in the shoots having a terminal bud and solitary side buds , the flowers in groups of one to five together on short stems, and the fruit having a groove running down one...
, potatoes (raw or cooked), pumpkins, radish
Radish
The radish is an edible root vegetable of the Brassicaceae family that was domesticated in Europe, in pre-Roman times. They are grown and consumed throughout the world. Radishes have numerous varieties, varying in size, color and duration of required cultivation time...
, rape
Rape
Rape is a type of sexual assault usually involving sexual intercourse, which is initiated by one or more persons against another person without that person's consent. The act may be carried out by physical force, coercion, abuse of authority or with a person who is incapable of valid consent. The...
, rose
Rose
A rose is a woody perennial of the genus Rosa, within the family Rosaceae. There are over 100 species. They form a group of erect shrubs, and climbing or trailing plants, with stems that are often armed with sharp prickles. Flowers are large and showy, in colours ranging from white through yellows...
, sorrel
Sorrel
Common sorrel or garden sorrel , often simply called sorrel, is a perennial herb that is cultivated as a garden herb or leaf vegetable...
, spinach
Spinach
Spinach is an edible flowering plant in the family of Amaranthaceae. It is native to central and southwestern Asia. It is an annual plant , which grows to a height of up to 30 cm. Spinach may survive over winter in temperate regions...
, sweet pea
Sweet pea
Sweet pea is a flowering plant in the genus Lathyrus in the family Fabaceae , native to the eastern Mediterranean region from Sicily east to Crete....
, thistle
Thistle
Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles often occur all over the plant – on surfaces such as those of the stem and flat parts of leaves. These are an adaptation that protects the...
, thorn apple, tomatoes (well liked), turnip
Turnip
The turnip or white turnip is a root vegetable commonly grown in temperate climates worldwide for its white, bulbous taproot. Small, tender varieties are grown for human consumption, while larger varieties are grown as feed for livestock...
, wheat
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
, yarrow
Yarrow
Achillea millefolium or yarrow is a flowering plant in the family Asteraceae, native to the Northern Hemisphere. In New Mexico and southern Colorado, it is called plumajillo, or "little feather", for the shape of the leaves. In antiquity, yarrow was known as herbal militaris, for its use in...
, zinnia
Zinnia
Zinnia is a genus of 20 species of annual and perennial plants of family Asteraceae, originally from scrub and dry grassland in an area stretching from the American Southwest to South America, but primarily Mexico, and notable for their solitary long-stemmed flowers that come in a variety of bright...
. They will eat sweet lupin
Lupin
Lupinus, commonly known as Lupins or lupines , is a genus in the legume family . The genus comprises about 280 species , with major centers of diversity in South and western North America , and the Andes and secondary centers in the Mediterranean region and Africa Lupinus, commonly known as Lupins...
es, but will reject bitter lupin
Lupin
Lupinus, commonly known as Lupins or lupines , is a genus in the legume family . The genus comprises about 280 species , with major centers of diversity in South and western North America , and the Andes and secondary centers in the Mediterranean region and Africa Lupinus, commonly known as Lupins...
es and other plants with high quinolizidine
Quinolizidine
Quinolizidine is a nitrogen-containing heterocyclic compound. Some alkaloids are derivatives of quinolizidine....
alkaloids. Snails also avoid plants that produce other defensive chemicals, defensive stem hairs, etc.
Snails usually prefer juicy leaves and vegetables over dry ones. If you feed snails vegetable trimmings, damaged fruit, and cooked potatoes, promptly remove uneaten food as it will quickly spoil. You may supply bran that is wet or sprinkle dry bran over leafy vegetables. The diet may consist of 20% wheat bran while 80% is fruit and vegetable material. Some growers use oats
OATS
OATS - Open Source Assistive Technology Software - is a source code repository or "forge" for assistive technology software. It was launched in 2006 with the goal to provide a one-stop “shop” for end users, clinicians and open-source developers to promote and develop open source assistive...
, corn meal, soybean meal
Soybean meal
Soybean meal also known as Soyabean Oil Cake is a flour made by grinding the solid residue of soybean oil production. It is widely used as a filler and source of protein in animal diets, including pig, chicken, cattle, horse, sheep, and fish feed....
, or chicken
Chicken
The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird...
mash. Laying mash provides calcium, as does crushed oyster
Oyster
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....
shells. Snails also may eat materials such as cardboard (but do not purposely feed it to them); they can eat through shipping cartons and escape. Snails may sometimes eat, within a 24-hour period, food equal to 10%, and occasionally as much as 20%, of their body weight
Body weight
The term body weight is used in daily English speech as well as in the contexts of biological and medical sciences to describe the mass of an organism's body. Body weight is measured in kilograms throughout the world, although in some countries it is still measured in pounds or stones and pounds...
. Active snails deprived of food will lose more than one-third of their weight before they starve to death—a process that takes 8 to 12 weeks. Estivating snails can survive much longer.
Supply calcium at least once a week if it is not available in the soil. It should not contain harmful salts or be so alkaline as to burn the snails. Mix calcium with wet bran or mashed potatoes and serve on a pan; this will keep any leftover food from rotting on the ground.
Some researchers use chicken mash for feed. You can cut a plastic pipe in half lengthwise to make two troughs which can be used as feeders for mash. Mix laying mash (used for egg-producing hens) into the feed to provide calcium for the snails' shells. Commercial chicken feeding mash is around 16% to 17% protein, from fish meal and meat meal, making it good for growing snails. Supplying mash to hatchlings might reduce cannibalism. Two feeds that snails like and that promote good growth are: (A) broiler finisher mash consisting of 7% broiler concentrate, 58% corn, 16% soya, 18% sorghum, 7 % limestone flour (40% Ca); and (B) chicken feed (pellets) for layers consisting of 5% layer concentrate, 10%, corn, 15% soya, 20% sorghum, 44% barley, 6% limestone flour (40%Ca).
Pellets are fine for larger snails, but mash is better for younger ones. Partially crush pellets if you feed them to young snails. Snails do not grow well if rabbit pellets are their primary diet. Snails show a distinct preference for moist feed. Ensure easy access to enough water if you feed snails dry mash.
Be sure to frequently clean the feed and water dishes. The amount of feed a snail eats depends very much on air humidity and on the availability of drinking water. You can serve clean drinking water in a shallow container to reduce the risk of the snail drowning. Some types of chicken waterers may be suitable. Other factors (e.g., temperature, light intensity, food preferences versus food supplied, etc.) also affect feeding. A compromise, until you find the optimum feed, is to feed half green vegetable material and half chicken feed/grain/animal protein.
Young H. aspersa readily eats milk powder. Its rapid rate of assimilation promotes rapid growth.
Diseases and pests
Good hygiene can prevent the spread of disease and otherwise improve the health and growth rate of snails. Food is replaced daily in order to prevent spoilage. Earthworms added to the soil help keep the pen clean.Parasites
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
, nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
s, trematodes
Trematoda
Trematoda is a class within the phylum Platyhelminthes that contains two groups of parasitic flatworms, commonly referred to as "flukes".-Taxonomy and biodiversity:...
, fungi, and microarthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s can attack snails, and such problems can spread rapidly when snail populations are dense. The bacterium Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
causes intestinal infections that can spread rapidly in a crowded snail pen.
Possible predators include rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s, mice
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...
, moles
Mole (animal)
Moles are small cylindrical mammals adapted to a subterranean lifestyle. They have velvety fur; tiny or invisible ears and eyes; and short, powerful limbs with large paws oriented for digging. The term is especially and most properly used for the true moles, those of the Talpidae family in the...
, skunk
Skunk
Skunks are mammals best known for their ability to secrete a liquid with a strong, foul odor. General appearance varies from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora...
s, weasel
Weasel
Weasels are mammals forming the genus Mustela of the Mustelidae family. They are small, active predators, long and slender with short legs....
s, bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s, frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
s and toad
Toad
A toad is any of a number of species of amphibians in the order Anura characterized by dry, leathery skin , short legs, and snoat-like parotoid glands...
s, lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s, walking insects (e.g., some beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
and cricket
Cricket
Cricket is a bat-and-ball game played between two teams of 11 players on an oval-shaped field, at the centre of which is a rectangular 22-yard long pitch. One team bats, trying to score as many runs as possible while the other team bowls and fields, trying to dismiss the batsmen and thus limit the...
varieties), some types of flies
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
, centipede
Centipede
Centipedes are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric animals with one pair of legs per body segment. Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of...
s, and even certain carnivorous snail species, such as Strangesta capillacea.
Population density
Population density also affects successful snail production. Pens should contain no more than six to eight fair-sized snails per square foot, or about four large H. pomatias; or figure one kilogram per square meter (about .2 pounds of snail per square foot), which automatically compensates for the size of the snails. If you want them to breed, best results will occur with not more than eight snails per square meter (0.8 per square foot). Some sources say that, for H. pomatia to breed, 2 to 4 snails per square meter (0.2 to 0.4 per square foot) is the maximum.Snails tend not to breed when packed too densely or when the slime in the pen accumulates too much. The slime apparently works like a pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
and suppresses reproduction. On the other hand, snails in groups of about 100 seem to breed better than when only a few snails are confined together. Perhaps they have more potential mates from which to choose. Snails in a densely populated area grow more slowly even when food is abundant, and they also have a higher mortality rate. These snails then become smaller adults who lay fewer clutches of eggs, have fewer eggs per clutch, and the eggs have a lower hatch rate. Smaller adult snails sell for less. Dwarfing
Dwarfing
Dwarfing is a characteristic in plants and animals whereby one or more members of a breed or cultivar are significantly smaller than standard members of their species...
is quite common in snail farming and is attributable mainly to rearing conditions rather than heredity
Heredity
Heredity is the passing of traits to offspring . This is the process by which an offspring cell or organism acquires or becomes predisposed to the characteristics of its parent cell or organism. Through heredity, variations exhibited by individuals can accumulate and cause some species to evolve...
factors. Crowding snails is false economy. A recommended rate for H. aspersa is not more than one-third pound per square foot (3.6 kg/m²) of soil surface for snails that weigh more than 1 gram and not more than 0.2 pound per square foot (2.2 kg/m²) for snails that weigh less. (One ounce is about 28 grams.)
Turning snails into escargots
Snails are mature when a lip forms at the opening of their shell. Before they mature, their shells are more easily broken, making them undesirable. For H. aspersa, commercial weight is 8 grams or larger. The nutrient composition of raw snails (per 100 grams of edible portion), according to information from the nutrient databank of France, is:- EnergyFood energyFood energy is the amount of energy obtained from food that is available through cellular respiration.Food energy is expressed in food calories or kilojoules...
: 80.5 kcalCalorieThe calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit of energy, the joule...
(337 kJ) - WaterWaterWater is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
: 79 g - ProteinProteinProteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
: 16 g - Available carbohydrates: 2 g
- FiberFiberFiber is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread.They are very important in the biology of both plants and animals, for holding tissues together....
: 0 g - FatFatFats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...
: 1 g - MagnesiumMagnesiumMagnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...
: 250 mg - CalciumCalciumCalcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
: 170 mg - IronIronIron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
: 3.5 mg - Vitamin CVitamin CVitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...
: 0 mg
Restrictions and regulations in the United States
The same snails that some people raise or gather as food also are agricultural pests that cause considerable crop damage. Introduced slug and snail varieties tend to be worse pests than native species, probably due in part to the lack of natural controls. Snail pests attack crops ranging from leafy vegetables to fruits that grow near the ground, such as strawberries and tomatoes, to citrus fruits high up on trees.The Federal Plant Pest Act defines a plant pest as "any living stage (including active and dormant forms) of insects, mites
MITES
MITES, or Minority Introduction to Engineering and Science, is a highly selective six-week summer program for rising high school seniors held at the Massachusetts Institute of Technology. Its purpose is to expose students from minority, or otherwise disadvantaged backgrounds, to the fields of...
, nematodes, slugs, snails, protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
, or other invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
animals, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, fungi, other parasitic plants or reproductive parts thereof; viruses; or any organisms similar to or allied with any of the foregoing; or any infectious
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
substances, which can directly or indirectly injure or cause disease or damage in or to any plants or parts thereof, or any processed, manufactured, or other products of plants..." The Animal and Plant Health Inspection Service
Animal and Plant Health Inspection Service
Animal and Plant Health Inspection Service is an agency of the United States Department of Agriculture responsible for protecting animal health, animal welfare, and plant health. APHIS is the lead agency for collaboration with other agencies to protect U.S. agriculture from invasive pests and...
(APHIS) categorizes giant African snails as a "quarantine significant plant pest." The United States does not allow live giant African snails into the country under any circumstances. It is illegal to own or to possess them. APHIS vigorously enforces this regulation and destroys or returns these snails to their country of origin.
Since large infestations of snails can do devastating damage, many states have quarantines against nursery products, and other products, from infested states. Further, it is illegal to import snails (or slugs) into the U.S. without permission from the Plant Protection and Quarantine Division(PPQ), Animal Plant Health and Inspection Service, U.S. Department of Agriculture. APHIS also oversees interstate transportation of snails. Anyone who plans to "import, release, or make interstate shipments of" snails, must complete APHIS's PPQ Form 526, Application and Permit to Move Live Plant Pests and Noxious Weeds. Submit the form to your State regulatory official. The state will process the request and make a recommendation to APHIS who will then make a decision.
Information on Plant Pest Permits is available at APHIS's web site http://www.aphis.usda.gov/ppq/permits/.
The Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA) regulates the canning of low-acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
foods such as snails. According to FDA, "establishments engaged in the manufacture of Low-acid or Acidified Canned Foods (LACF) offered for interstate commerce in the United States are required. . .to register their facility. . .and file scheduled processes for their products with" the FDA. This does not refer to fresh products. For appropriate forms, contact: LACF Registration Coordinator, HFS-618, Food and Drug Administration, Center for Food Safety and Applied Nutrition, 200 C Street, S.W., Washington, D.C. 20204. Telephone: (202) 205-5282. FAX: (202) 205-4758 or (202) 205-4128.
Improper canning of low-acid meats, e.g., snails, involves a risk of botulism
Botulism
Botulism also known as botulinus intoxication is a rare but serious paralytic illness caused by botulinum toxin which is metabolic waste produced under anaerobic conditions by the bacterium Clostridium botulinum, and affecting a wide range of mammals, birds and fish...
. When canning snails for home consumption, carefully follow canning instructions for low-acid meats to prevent food poisoning.
State laws also may apply to imports into certain states and to raising snails in a given state. Your state also may want to inspect and approve your facility. Thus anyone who plans to raise snails also should check with their State's Agriculture Department.