The Giant African Snail (GAS), Achatina (Lissachatina) fulica (Bowdich) (Stylommatophora: Achatinidae), a native of east Africa, was discovered in Trinidad in 2008 in Alyce Glen, Diego Martin. According to the global invasive species database, A. fulica is the second worst invasive alien species in the world. Currently, as of August 2017, the snail has infested over 17 areas in Trinidad and is fast becoming more and more difficult to contain.  The shell of fully grown adults has 7 to 9 ridges or whorls. It is normally reddish-brown with faint yellowish vertical markings. The length of the adult shell may exceed 20cm, but usually averages between 5 and 10cm .This snail feeds on over 500 species of vegetation and is a pest of extreme significance to both crop production and human health. Given also, that Trinidad is self-sufficient in vegetable production, the burden of this pest and threat to our local food security is significant. This pest reproduces rapidly, has limited predators, hibernates during unfavourable conditions such as in the dry season and is hermaphroditic having both male and female sex organs. The GAS is primarily a nocturnal pest and usually becomes active at sunset. The snails are very active during the rainy season or during rainfall events in the dry season. This pestiferous snail has the ability to produce as much as 1,000 eggs annually during the rainy season but can also reproduce and be active in the dry season once favourable conditions are available. The average life span of the GAS is between 3 - 5 years, however, some adults are known to reach the age of 9 years.

The Giant African Snail can be considered the only agricultural herbivorous pest which is a threat to public health since it is a vector of the rat lungworm, Angiostrongylus cantonensis, which causes eosinophilic meningoencephalitis in humans. The public is at risk from consuming agricultural produce from snail infested fields.  This snail is now classified as a notifiable pest and must be reported to the Ministry of Agriculture, Land and Fisheries.  The snail hotline numbers are: Trinidad - 646-6284 and Tobago - 639-4616. You can also email your photograph or report of the snail sighting to snailreport@ gmail.com. Failure to report the presence of this pest can result in a fine of $5,000.00.

Once you have made your report and it is confirmed that the Giant African Snail is present on your properly you must make every effort to eradicate the snail. You must wear gloves at all times when handling snails or working in areas of your property where the snails are present or are suspected to be present.  The first step would be to examine your property and to remove all possible hiding places for the snail. These include bushy areas, debris, mulch, garbage heaps, compost heaps, logs, brick holes and blocked drains. The snail can also be found in trees, high on the sides of building and in open sewage tanks. When you remove or discard items and debris from your property it is advised that you carefully inspect for the presence of snails and eggs before removing it from your property. This also applies to inspecting your vehicle since snails can infest new areas as they are known to "hitch hike" to other areas on objects.

Sanitation must be coupled with the application of bait (Metaldehyde or Iron Phosphate formulations) available at any agricultural shop.  The application of bait for the snails should be simultaneously done with rat baiting once rats are present in or around your property.  The snail can be manually crushed by stepping on them once you are wearing rubber boots. You should wash your boots with bleach solution after crushing the snails.  Crushed snails should be buried or burnt once approval for burning on your property is granted.  The snails can be drowned in a very concentrated salt solution once the vessel used for drowning the snails is filled completely to the top and covered for a period of 24 hours. The dead snails should then be buried or incinerated. Bag salting snails can also be done by placing sufficient salt in a bag to completely cover the snails and tightly tying the bag and inserting into another bag which is also to be tightly tied.

The dead snails should preferably be buried to avoid fly infestation attributed to decaying snail carcasses. It is recommended that the snails can be collected and burnt but approval must be obtained from the Fire Services to practice this.  Snail shells are vessels which can collect water and breed mosquitoes. It is imperative that snail shells are not left around your property especially given the threat of the Dengue and Zika viruses in Trinidad. These snails are attracted to household waste and as a precaution if snails are in close proximity to your garbage disposal area you should bait to avoid the spread of the snail to new areas via the garbage trucks.

The general public should ensure that all locally produced fruits and vegetables are inspected for the snails, snailets (juveniles) and snail excreta. Discard anything that has been contaminated by the Giant African Snail. Ensure that all produce is thoroughly washed before preparation or direct consumption.

Before you use any mechanical methods for weed control strategies, such as lawn-mowers or weed wackers, ensure that you inspect the area for snails and ever more so ensure that you wear a face shield/protective eye gear and cover your mouth with a disposable  face mask.
The presence of the Giant African Snail requires that everyone, regardless of whether you have the snail in your property, be aware of its threat to our national food security and human health. Please visit the website for the Ministry of Agriculture, Land and Fisheries for more information on the Giant African Snail at http://www.agriculture.gov.tt/
Please see the attached photographs to assist with the identification of the Giant African Snail on your property.

GIANT AFRICAN SNAIL ALBUM BY DR. MARCUS NICHOLAS A. RAMDWAR

Giant African Snail (GAS). Photograph by Dr.Marcus Ramdwar, February, 2017

GAS extended from shell. Photograph by Dr. Marcus Ramdwar, February 2017.

Snail mating behaviour. Photograph by Dr. Marcus Ramdwar, January 2017.

GAS eggs day 1. Photograph by Dr. Marcus Ramdwar, August 2017 

Young GAS eating a corn cob on a corn plant. Photograph by Dr. Marcus Ramdwar, August 2017 

GAS on an ochro plant in Mt Lambert. Photograph by Dr. Marcus Ramdwar, August 2017

GAS on a garbage receptacle. Photograph by Dr. Marcus Ramdwar, August, 2017.

Shells from dead GAS a collection vessel for water and site for mosquito breeding. Photograph by Dr. Marcus Ramdwar, July, 2017.

GAS feeding behavior on breadfruit and cabbage leaves. Photograph by Dr. Marcus Ramdwar, July, 2017.

GAS excrement on the soil (left) and on a plant (right). Photograph by Dr. Marcus Ramdwar, August, 2017.

The appearance of the GAS during hibernation (aestivation) when conditions are unfavourable. Photograph by Dr. Marcus Ramdwar, June, 2017.