Download The Control Program for Giant African Snail Achatina fulica in

The Control Program for
Giant African Snail
Achatina fulica in Barbados
Ian H Gibbs, Senior Entomologist
Entomology Section
Ministry of Agriculture, Food, Fisheries &
Water Resource Management, Barbados
Barbados
 Geology
– Subduction zone South America & Caribbean tectonic plates
– Composed of coral roughly 90 m thick over limestone
• Area
⎯ 21 miles (34k) x 14 miles (23k), about 166 sq mi.
• Rainfall
− Precipitation ranges from 40 – 90 inches per year, mean of 59
inches (1,491mm, Carib. Inst. Of Meterology & Hydrology)
− Tropical monsoon climate (Koppen classification)
− Dry season (Dec – May), wet season (June – Nov)
• Drinking water
− Aquifers
− Catchments (coral/limestone gullies) feed aquifers
Detection and Identification
 First Report - September 27th, 2000 by a
visiting Australian entomologist
 Site - Spring Garden, St. Michael Parish
 Confirmed - October 9th, 2000
by Dr. David Robinson, USDA through the
auspices of the FAO
Distribution of GAS in Barbados (2008)
.
Bulkeley Factory Yard
Refuge for the snail
is provided by old
wood and factory
machinery
Cricket field, Spring
Garden, nr. Courts
A concealed refuse heap at the
edge of the field
Juveniles living
beneath and feeding
on the rotting
breadfruit in the refuse
Thorne’s Gap
Most of the sites (80%) are in residential areas
In blocks and derelict houses
In Gullies - Cave Hill, St. Michael
Newbury
Snails can grow to
a large size
A gully provides an ideal habitat for the Giant African
Snail
Surveillance
 Area around the ports of entry
 Increased surveillance on landscape/plant
nursery/haulage businesses
 GAS locations recorded mainly based on reports from
general public
 Use of media in disseminating information
 Town Hall meetings
 Flyers
 Alerts to general public to reduce movement of
infested materials from one area to another
 Place information in a GIS database for tracking and
control planning purposes
Town Hall – Public Education
Achatina fulica, giant African snail
Megalobulimus oblongus
Orthalicus maracaibensis
Zachrysia provisoria
Bulimulus guadalupensis
Subulina octona
Control Program
 Town Hall Meetings
- Dissemination of information
- Training on application of molluscicides
- Distribution of molluscicides
- Surveys of affected areas
• Private land owners treated their properties –
accounted for ~75% of all treatments
• Ministry treated common areas, right of ways, and
environmentally sensitive areas (~25%).
Control Measures
metaldehyde based molluscicides were used.
available as bait pellets, soluble powder or liquid
suspension.
 Blitzem Pellets:
bait pellet 1.5% metaldehyde
 Deadline Pellets: bait pellet
4.0% metaldehyde
 Meta-metaldehyde: soluble powder 100%
 Murphy Slugit liquid: liquid suspension
20%
Metaldehyde Formulations
Blitzem was the predominant product used in early stages of the control
program, later transitioning to Deadline pellets as they were more durable
to rainfall.
Air Blower Dispersal of Pellets
Good evidence of effective control
Newbury, St. George near a gully
Transition to Bounty Program 2009
 The Ministry of Agriculture decided that the
expenditure of funds to purchase molluscicides
for distribution was unsustainable.
− Molluscicide program 2001 - 2009
 They opted for implementing and expending
those funds in bounty program to control GAS.
– Bounty program 2009 to date.
Guidelines of the GAS bounty
program
 Bounty program started in March 2009
 $0.50 Bds per pound ($.025 US)
 Collect and deliver to Ministry of Agriculture
 Snails weighed and receipt given to collector
 Collector paid at later date
 Snails incinerated at MOA facility
Burning snails at Graeme Hall
GAS Bounty Program collections
Amount of GAS Collected Monthly in the Bounty Programme
100,000
90,000
80,000
lbs GAS Collected
70,000
60,000
April 09- March 10
50,000
April 10 - March 11
40,000
April 11- March 12
30,000
April 12- March 13
20,000
10,000
0
Months
GAS Bounty Program
From its inception in late March 2009 to the end of January
2013, the amount of GAS collected and burnt was
392 Tons!!!!
This represents over
12,000,000 snails destroyed
Possible reasons for the reported decline in
Giant African Snail populations across
Barbados in recent times
H. Ian Gibbs
Entomology Section
Ministry of Agriculture,
Food, Fisheries & Water
Resource Management
Reported Predators of GAS in Barbados
 Reports of a number of Predators feeding on
GAS on the island are:
Mongoose (Herpestes auropunctatus)
Blackbird (Quiscalus lugubris)
Cattle egret (Bubulcus ibis)
Duck (Cairina moschata)
Chicken (Gallus domesticus)
Millipede (Orthoporous antillensis)
Centipede (Scolopendra subspinipes)
Firefly or Click beetle (Aspisoma ignitum)
Rats (Rattus rattus) and/or (Rattus norvegicus)
Toad (Bufo marinus)
Mite parasitic on GAS in Barbados
 A mite, Riccardoella sp., has been found to be
parasitic on GAS in Barbados (Angela Fields, UWI
Biology Dept. Cave Hill). Its specific name is yet to be
determined
 Two other species of mite, Riccardoella limacum and
R. oudemansi are known to be parasitic on terrestrial
gastropods and impair their development by sucking
their blood and body fluids
Control by people across the island
Barbadians have used various methods to control
GAS on their properties and surrounding areas:
- Baiting with molluscicide pellets like Deadline,
Blitzem and Sluggo
- Collection of snails and drowning, crushing or
burning them
- Spraying the snails with a range of different
products such as Clorox, Jeyes Fluid and Slugit
- Dusting snails and property with white lime
Conclusions
The reported significant decline in GAS
populations across the island may thus be
attributed to:
 The removal and destruction of over 12,000,000
snails (and the eggs they would have laid) from
2009 to present
+
 An increasing level of predation by 10 predatory
species and parasitism by one mite species
+
 Persons across Barbados using a range of
different control methods