How to combat the Giant African Snail?

Last week we touched on invasive species in Trinidad and Tobago and many readers asked about the Giant African Snail. What do they do? How to get rid of it? Do they contact the authorities? This and more will be answered in our final article of the year.

The origin:

The Giant African Snail was first sighted in East Africa, specifically in Kenya and Tanzania. It is a highly invasive species and a disastrous pest in the world of agriculture. This snail eats over 500 species of plants and is a vector for diseases such as rat lungworm which is a parasite. Once contracted this parasite can cause meningitis. According to the government of Trinidad and Tobago, Giant African Snails were deliberately introduced to the Caribbean in the 1980s. It was first sighted in Trinidad in October of 2008. At first, the snails were contained in the Diego Martin area but eventually spread through the entire North-West portion of the island. Recently, sightings of these snails have been reported far East, reaching places like Valencia and even further Central reaching areas like Cunupia and Las Llomas. The spread of these pests is due to land clearing and transportation. The snails can easily attach themselves to soil or plants being moved around the country or attach themselves to moving vehicles.

Figure 1: showing  group of Giant African Snails (Loop News TT 2021)

What to do if you suspect there are snails present?

Perhaps you have noticed bite marks on your plants or a slimy substance on them and you suspect it may be due to the Giant African Snail; you should look for them during the late evening or early morning. These snails are nocturnal and are most active during dust and dawn. They prefer moist or damp conditions and usually avoid direct sunlight. Common hiding places are under bricks, rocks, leaves, logs, decarded containers and ledges or in/on brick holes, trees and plants.

Figure 2: showing what a plant would look like if a snail was eating it
(All About Slugs 2021) 

The First Line of Action:

If a snail is spotted firstly, ensure that it is in fact a Giant African Snail by using images to compare what you see to a Giant African Snail or by looking for key markers. These markers include: the shell of the snail is conical and usually ranges in size from 5 to 13 centimetres but can grow up to 30 centimetres, the shell usually has more than seven whorls (a whorl is a complete revolution of the shell giving it a swirly effect).

Secondly, once you have identified that it is indeed the Giant African Snail, report your sighting by calling 646-6284 and email pictures of the snails to snailreport@gmail.com so that the authorities can also verify the snail.

Figure 3: showing a Giant African Snail eating corn (USDA APHIS 2021)

What can you do while waiting for the Authorities?

The best thing you can do is be mindful of spreading the snails. You can do this by inspecting your vehicles for snails that may have attached themselves. Refrain from throwing the snails into garbage bags or trash cans and refrain from moving the snails from the area it was sighted since this will only aid in the spread of these pests. When removing snails from vehicles or machinery, use gloves to prevent contamination and place them in a secure container. Be sure to look out for snail eggs in the process. The eggs are cream or light yellow in colour, oval-shaped, approximately half of a centimetre long and are laid in batches of 100 to 500 eggs.

 

Figure 4: Showing the whorls on the shell
(Florida Dept. of Agriculture and Consumer Services)

Let us combat the snail invasion in Trinidad and Tobago.

Be safe and have a Merry Christmas!