The Mosquito Research and Control Unit will treat almost 12,000 acres of mosquito-breeding swamp areas in Grand Cayman this week, and 800 acres of breeding sites in Cayman Brac and Little Cayman in the lead-up to the insects’ peak breeding season.
Early morning and late afternoon aerial operations will distribute small pellets designed to target mosquito larvae developing in aquatic habitats from West Bay to the north side of the island over a 10-day period, starting Wednesday, depending on weather.
Mosquito Research and Control Unit research manager Fraser Allen said three treatments are completed each year between May and November, with the effects of each treatment lasting around two months.
“This will significantly reduce the numbers of mosquitoes that emerge during the wet season. If this operation did not exist, the nuisance biting would be intolerable and would also have a detrimental effect on tourism,” Mr. Allen said.
“There are two rainfall peaks, June and September/October. Hence, this is the worst time for potential mosquito breeding when the eggs would hatch. The breeding is also related to tidal fluctuation in the swamps, so there could be a tidal brood during any time of the year or a rainfall and/or tidal brood between June to October.”
Mr. Allen warned mosquito biting is worse around sunset and sunrise.
“It is advisable to stay indoors at that time or wear long sleeves and pants,” Mr. Allen said. “Some other preventative measures may include using repellents and burning citronella candles on patios. Repellents appear to be particular to the person – some work for some and not others.”
While the mosquito control unit has been conducting aerial operations for more than 50 years, new technologies have enabled pellets to be applied to swamps more accurately and have reduced the need to use adulticide spraying, he said,
“The larviciding operation has cut down the mosquito emergence very significantly over the years,” Mr. Allen said.