The World’s Departments of Agriculture

Golden Apple Snail (GAS)
This species has been nominated as among 100 of the
"World's Worst" invaders( #73).

Based on its large distribution in many countries, i
t earns the designation of being “of highest priority” because of its potential to destroy crops and harm people.

Pomacea canaliculata (Lamarck, 1822)
May Be On the loose and should be considered extremely dangerous if not a native species!

Life form: mollusc (mollusk) behavior- amphibious

Where to be on the lookout!

Just Added June 25, 2008:
" You can now add Georgia and South Carolina to the list of US states where channeled apple snails have been introduced into the wild. I'm an invasive species biologist for the SC Department of Natural Resources, and we are now dealing with an infestation in several water bodies just on the edge of the Waccamaw National Wildlife Refuge near Myrtle Beach. As a matter of interest, you might like to know recent genetic work by researchers in Florida and the Philippines have determined that the species now introduced in FL, TX, GA, and SC are the island apple snail, Pomacea insularum, rather than the very similar golden apple snail, P. canaliculata...."

Apple snails naturally live in quiet rivers, ponds, swamps & wetlands. However, they also survive quite well in reservoirs, lagoons, drainage canals, paddy fields as well as any other irrigated agricultural areas and man-made lakes or water courses.

Native range: temperate Argentina northwards to the Amazon basin.

Introduced range: Most of southern, eastern and south-east Asia, including the Philippines, Japan, Taiwan, Vietnam, Cambodia, Thailand, Laos, Korea, Sri Lanka, parts of Indonesia and Malaysia, southern China, Singapore; also Hawaii, Guam, and Papua New Guinea; the Dominican Republic; the USA (Florida, Texas, California, Georgia and South Carolina - recent genetic work by researchers in Florida and the Philippines have determined that the species now introduced in FL, TX, GA, and SC are the island apple snail, Pomacea insularum, rather than the very similar golden apple snail, P. canaliculata. ). Apple Snails can even survive harsh environmental conditions such as pollutants in the water or low oxygen levels.

Pomacea canaliculata is widely distributed in lakes, ponds and swamps throughout its native range of the Amazon Interior Basin and the Plata Basin. This amphibious animal remains submerged during the day, hidden in vegetation near the surface. It is more active during the night when it leaves the water in search for fresh vegetation. The activity rate of this snail varies highly with the water temperature. At 18°C they hardly move around, this in contrast with higher temperatures e.g. 25°C. Nevertheless, Pomacea canaliculata is more resistant to lower temperatures than most other snails from the genus Pomacea (The Apple Snail Website, 1998-2003). Quote: ISSG


  • apple snail (English), channeled apple snail, Gold variant apple snail (English), Gelbe Apfelschnecke (German), golden apple snail (English), golden kuhol (English-Philippines), miracle snail (English-Philippines)
  • In the pet trade, they are referred to as Canas or mystery snails (Often, pet shops sell the dark colored Canas as mystery snails and the gold Canas as Golden Inca snails. (They are some of the largest of all Apple Snail species you will likely find in the pet store or fish store. )
  • Synonymous with Pomacea haustrum (from Thompson, 1997).

General Description:

Shell: The shell of this apple snail species is globose and relatively heavy (especially in older snails). The 5 to 6 whorls are separated by a deep, indented suture (hence the name 'canaliculata' or 'channeled'). The shell opening (aperture) is large and oval to round. Males are known to have a rounder aperture than females. The umbilicus is large and deep.

The size of these snails varies from 40 to 60mm (approx 1.5 to 2.5 inches) wide and 45 to 75 mm(approx. 1.75 - 3 inches) high depending on the conditions.
The colour varies completely yellow and green (cultivated forms) to brown with or without dark spiral bands (wild form). The shell growth of this species occurs mainly in spring and summer, while it stagnates in fall and winter,

Operculum: The operculum is moderately thick and corneous. The structure is concentric with the nucleus near the centre of the shell. The colour varies light (in young snails) to dark brown. The operculum can be retracted in the aperture (shell opening).

body: The colour of the body varies from yellow (cultivated), brown to nearly black, with yellow spots on the siphon, but not as much on the mouth as in Pomacea bridgesii. When at rest, the tentacles are curled under the shell.

Quoted from... AppleSnail Web Site


In Apple snails, sexes are separate. The females lay clusters of bright pink eggs attached to solid surfaces (rocks, walls, logs, emergent vegetation, trash) up to usually about 50 cm above the water surface. Eggs generally hatch within 7-15 days, but may take longer, probably depending on ambient temperature regime.
Adults mate for 3-4 hours anytime of the day among crowded plants where there is continuous water supply throughout the year. Reproductive output can be enormous. Clutch size is up to 1000, but average probably closer to 200-300 (1000-1200 eggs in a month). These massive clutches are laid every few weeks. Hatchlings are voracious feeders, grow quickly (maturing at about 2 months of age).
In nature, the first indication that there are applesnails around, may be these large patches of pink eggs.

Life Span:

Hatchlings grow and mature fast. Longevity is up to 4 years. Reproductive maturity is reached in 3 months to 2 years, depending on ambient temperature regime.

Eating Habits:

A highly generalist and voracious macrophytophagous herbivores (leaf eaters) . Most plants are eaten, however, they prefer young, soft plants. (preferenses include: rice seedlings, taro, duck weed, water hyacinth, algae, azolla, and other succulent leafy plants). They also eat decomposing organic matter.

They may, on occasion, feed on the eggs and juveniles of other snails. They will also eat decomposing matter.

As pets, they can also be fed with fish food. Remember, as voracious plant eaters, they aren't suited for planted aquariums.


Apple Snails are amphibious animals. They stay submerged during the day, hidden in the vegetation near the border and the surface. They are more active during the night, also leaves the water in search for fresh vegetation.
The activity rate of this snail varies highly with the water temperature. Below 18°C they hardly move around, this in contrast with higher temperatures (25°C). Nevertheless, Pomacea canaliculata is more resistant to lower temperatures than most other snails from the genus Pomacea.
information from...

information from the AppleSnail Web Site


1. A freshwater snail with a voracious appetite for water plants including lotus, water chestnut, taro, and rice.
This species was misguidedly introduced into many Asian countries as a potential food industry. However, very few people liked the tasteof it and it quickly became one of the most important pests of rice in the world. Ppopulations of apple snails can grow rapidly and it is difficult to control them due to their ability to withstand dry conditions in the mud.

In the Philippines alone, over half (1.2 to 1.6 million hectares) of rice fields are infested with the golden apple snail. The damage and economic loss have been devastating. Snails consume the base of rice seedlings and feed on new transplants. The costs of controlling the snail, replanting, and rice yield loss all account for economic loss

2. Beyond these costs on such cops as rice, there are the costs associated with damaging the ecosystem. Snails destroy plants and affect the food web. They may easily out-compete native species. They have helped in the decline of native Pila apple snails in south-east Asia.

3. Human health threats are also associated with this species. It may be a vector for disease and parasites such as the lungworm, which may cause the fatal eosinophilic meningoencephalitis disease in humans. Snails also contribute to skin irritations by being intermediate hosts to the associated trematodes. Pesticide side-effects include blurring vision and blindness, skin problems, and loss of nails

How Did It get Introduced to Foreign Habitats:

Aquarium trade: Developed as a domestic aquarium snail and sold in pet stores.
Live food trade: Imported legally and illegally for development of aquaculture projects for human food.
Nursery trade: Possibly introduced as eggs or small juveniles attached to aquatic plants.
Smuggling: Illegally introduced, usually for development as a human food resource.

Local dispersal methods
Aquaculture (local): Deliberately moved in order to establish new aquaculture facilities. Probably accidentally dispersed as eggs or more likely small juveniles on agricultural products. Deliberately introduced to uncontained wetland systems in the hope of harvesting the snails for food.
Escape from confinement: Escape (or even release) form aquaculture facilities is probably the major dispersal mechanism.

Other (local): Release of domestic aquarium snails.
Water currents: Probably one of the main means of dispersal within a watershed.

Interesting Facts:

  • Apple snails may estivate for up to 5 months of the year, meaning that even with drought conditions or imposed drying, they will likely survive. Their tolerance to pollution and low oxygen levels is high. They are able to live on many different types of plant matter, as well as decomposing organic matter. They have been called “eating machines” because they can eat 24 hours a day. They have an affinity for crops such as rice and taro.

  • Once an introduced species to many Asian countries as a food source, today it has no commercial value as such. However, now it is commonly used and sold by the pet trade as an aquarium pet.


Eradication of established populations is probably not possible. Numerous measures have been tried in attempts to control apple snails in agricultural settings. These include:

  • Several pesticides and molluscicides have been tried. As well as the costs, they are harmful to other species, including humans. Long-lasting effects on ecosystems may not be known for years. No chemicals are currently known to be safe, effective and cheap enough to use on a large scale, although various ones are in use, including ones which have been banned in countries such as Japan, Taiwan and the Philippines.

  • In rice and taro fields, hand picking is a successful method to control apple snail populations without harming the environment. The disadvantage is that it only works when done on regular base. The best results are obtained if the hand picking is done as a community effort. All visible snails should be collected with a scoop net or by hand. After collection the snails can be used for human consumption (beware of parasites!), crushed to serve as a food source for fish or destroyed otherwise. Eggs should not be forgotten during collection! Baited traps filled with lettuce, cassava and taro leaves can be used to attract the snails and to facilitate the collection. All vegetation and obstacles around fields should be removed as much as possible as the snails need this to deposit their eggs. When there are no suitable eggs-laying sites available, the snails are forced to deposit the eggs on the bare ground where the eggs are very vulnerable and easily fall into the water, which drowns the eggs. Before draining a field, make shallow trenches so that the snails will congregate in the trenches and can be captured easily.

  • Many countries have implimented a range of cultural and mechanical control measures; however, None of these methods have proven entirely effective, safe, or economically viable. And, none are likely to be appropriate in natural ecosystems. A good article can be found on
    Today, scientists taking a differnet approach to this problem and are studying genetic manipulation to produce snails which reproduce less. .This may be the best long-term solution though it is still is not avaialable.

  • Naturally occurring biological control agents: (From
    • Red ants feed on the eggs.
    • Ducks eat the flesh and young snails.
    • Field rats bite on the shell and eat the flesh.

Legalities of Keeping Golden Apple Snails:

I am presently looking into the actual legalities of owning pet apple snails (cannas, mystery snails). I cannot find that they are actually illegal to own in any country as a pet. However, owners must take the initiative to be responsible care-givers. The release of these snails into nature could be devastating no matter which country they reside in.

USA: Pomacea canaliculata (Channeled or Golden Apple Snail) are banned for interstate movement or import into the United States.

Quarantine Areas:

California -The entire state
Florida -The entire state
Texas -The entire state
Hawaii -The entire state
North Carolina - The entire state
Other states or territories hereinafter which may be found to be infested.

World Contacts For Information:


Be a responsible pet owner and never release these snails into nature. This way, you will be part of the solution not the problem and YOU WILL FEEL GOOD!

Other Similar Species:

  • Pomacea Bridgesii

Good Web Sites for more information:

Pet Sites:


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