by Melissa Rollock
Over a decade ago, Barbados was invaded by an alien species which threatened life as we know it. It invaded our fields and hills and even our homes. It wasn’t long after the first sightings were reported that this “outsider” multiplied at such a rate that it outnumbered the local population. It decimated crops and threatened our livelihoods and health. The outlook seemed bleak.
But, after 13 years of waging war, the Ministry of Agriculture, Food, Fisheries and Water Resource Management is reporting a major victory in the battle against the Giant African Snail — with a significant reduction in the population. To understand the magnitude of this achievement, one has to fully comprehend the breeding capacity as well as the destructive potential of the snail.
Firstly, they are considered the most dangerous land snails in the world and have reportedly attacked over 500 different plant species. They may lay up to 1,200 eggs annually and young snails may cause serious damage. Their diet of choice includes: breadfruit, cassava, papaya, peanuts, most vegetables, living plants and flowers.
Head of the Ministry’s Entomology Section, Ian Gibbs, credited three main aspects for the decline in the populations of the Giant African Snail — the Ministry’s Bounty Programme; natural predators such as the mongoose; blackbird; cattle egret; millipede; centipede; toad and rat and control measures taken by average citizens.
“The Giant African Snail Bounty Programme was started in late March, 2009 where people have been collecting snails on a regular basis and when we collect them from those persons, we bring them here to Graeme Hall, [Christ Church] and burn them. Since that time until the end of last month, we have destroyed some 392 tonnes of snails.
“This represents well over 12 million snails that have been removed from the populations out there. If you multiply that by the number of eggs that each of those snails normally produce, then that number runs into the billions. So you will see that a very significant amount of snails and potential snails have been removed from the environment,” Gibbs said.
“In addition to that, there have been reports of a number of predators feeding on the snails. We’ve had numerous [accounts] from people actually seeing these predators eating [them]. The third aspect which could’ve led to the decline was the constant control measures that many Barbadians have been doing on their own across the island.
“These would include things like collecting the snails and crushing them, burning them, putting them in Clorox water or salt water, using bait, spraying them with a range of different [chemicals] and dusting the property with white lime,” he added.
Gibbs disclosed that for “well over a year now” the ministry had been receiving reports from people across the length and breadth of Barbados about a noted decline in the snail populations in their specific areas.
“I personally have seen it myself. I live in St. Thomas in what was a highly infested area and for about a year-and-a-half or more, I have seen a steady reduction in the number of Giant African Snails and this seems to have been mirrored right across the island. Recently, a small farmer told me he is now able to plant crops in his fields again that he couldn’t plant before because there has been a radical reduction in the amount of snails in his fields,” he stated.
The Entomologist said another entity was also responsible for the reduction in snails — a tiny mite or parasite known as the Riccardoella species. He explained that it was discovered by the Biology Department of the University of the West Indies and there were at least two other species — the Riccardoella limacum and Riccardoella oudemansi which were recorded in other parts of the world as being parasitic to the Giant African Snail. These mites impair the development of the snail by sucking its blood and body fluids.
While the reduction in the snail is an accomplishment that should be celebrated, Gibbs urged Barbadians not to become complacent, but to continue their efforts to control the pest. He explained that the main thrust was to control it since it would be difficult to eradicate the snail from these shores.
“They will always be with us,” he lamented.