Page 23 - The Villager April 2021

Nature

maturity five to eight months after hatching. and that’s how a
plague of giant african land Snails can develop in a relatively
short period of time.
the giant african land Snail is now found on every continent
around the globe (except for antarctica). apart from being
smuggled across borders by exotic pet traders, it is transported
Little achatina By tiMur V. VoronKoV
over large distances via cargoes of agricultural products and, as it
can survive in a state of aestivation (dormancy to avoid excessive
heat and dryness) for years, just as authorities declare that they
have the infestation under control, when weather conditions
improve, out they pop again.

WHY ARE THEY SUCH A THREAT TO HUMANS AND THE
ENVIRONMENT?
• They are voracious feeders, consuming around 500 different
species of plants. Not only do they climb into and devastate
agricultural crops such as coffee, cocoa and rubber plantations,
they also love fruit, vegetables, nuts and grains. they are
known to eat the bark and stems of trees, seaweed, lichens,
Achatina fulica eggs By Ken WalKer, MuseuM Victoria fungi and even other snails.
• Because they need calcium for their shells, they are capable of
eating the plaster off buildings, as well as sand, concrete and
even bones.
• They are hosts to a number of parasites, including
Angiostrongylus cantonensis, a nematode (roundworm) that
causes eosinophilic meningoencephalitis in humans.

HOW CAN ONE ERADICATE AND DISPOSE OF THEM?
• The first message here comes across loudly and clearly – DO
Giant African Land Snail (Achatina fulica) in Hyderabad. Not SImPly throw them IN yoUr rUbbISh DeStINeD For
Opposite page: Achatina fulica seen in a suburban garden laNDFIll!
on the Highveld.
• Spraying them with vinegar is suggested, or sprinkling them
with Diatomaceous earth could be a solution.
one of the largest terrestrial gastropods, the giant african • Surround your plants with rings of wheat bran or corn bran –
land Snail (Achatina fulica) hails from east africa and its you can buy these products from health food stores. they are
natural habitat stretches all the way from the north-eastern eaten by slugs and snails and the ingested bran then causes
region of Kwazulu Natal through mozambique, tanzania and desiccation and death. this is a totally organic solution, and
Kenya to Somalia and ethiopia. It has an average lifespan of if wildlife eat the corpses, they are getting extra nutrition.
5 – 7 years, although it can live longer in ideal conditions. this however, you need to replenish the bran regularly in rainy
snail can grow up to 20cm in length and its shell can extend weather.
up to 7cm in height. when it is fully grown, its shell will have • Although this has not been discussed in any of the research
between 7 and 9 spirals, which are normally dark or medium material available, speaking as a true South african male, I
brown with stripes at intervals. would suggest incinerating them along with any eggs that
although classified as hermaphrodites, (having both you find. and then burying the ash under a reasonable layer
male and female sex organs), reproduction requires cross- of soil in a corner of the garden.
fertilisation. mating involves both a ‘getting to know each
other phase’ and copulation which normally takes place at whatever you do, with the giant african land Snail featuring
night. From a single mating, the individual that received the prominently on the list of Top 100 Most Invasive Species in the
sperm can produce batches of fertilised eggs over a period of World, it’s recommended that the handling (using suitable gloves
months, although the sperm can also be stored by the snail for and other protection) and disposal of these ‘cute snails on steroids’
up to two years before fertilising any eggs. should be done with caution.
between 100 and 500 eggs are laid at a time. the eggs hatch
one to three weeks later and the baby snails reach sexual Resources: www.aphis.usda.gov www.cabi.org www.biokids.umichu.edu

The Villager • Issue 4 2021 • 21