Nāhiku LFA aerial treatment
Aloha!
The Little Fire Ant (LFA) infestation in Nāhiku is large, and distributed through very rough terrain and dense vegetation. Using traditional ground-based techniques, the Maui Invasive Species Committee (MISC) is unable to treat the infestation in the comprehensive manner needed for successful eradication. Because of this, MISC has developed an aerial bait delivery system.
Aerial treatments of the Nāhiku LFA Infestation are planned to occur every six weeks for a period of at least one year. The schedule below shows our best estimate of when these treatments will take place. However, operations such as this are subject to a variety of factors that can cause delays, and the safety of the helicopter crew, our crews on the ground, and the residents of the treatment zone is our highest priority. In addition, there are factors (such as heavy rain) that can greatly diminish the effectiveness of a particular treatment. As a result, treatments may be delayed at the last minute due to factors beyond our control. We will endeavor to keep the schedule shown on this page as up-to-date as possible, but know that rapidly changing conditions may lead to unannounced delays or even interruptions to treatments that are already underway.
Treatment Schedule
Methods
Our goal is to eradicate all Little Fire Ants. The large infestation in Nāhiku could potentially contain several million queens and several billion worker ants distributed throughout the landscape – on the ground, up in the trees and other vegetation, and around the houses and other structures. But it is the queens that produce the workers -- and so every single queen must be eliminated to achieve eradication. The product we will use in the aerial treatment of Nāhiku is an insect growth regulator that eliminates ant colonies indirectly (as described below). It will be mixed with an edible bait that the ants find attractive: the worker ants will bring the bait back to the nest and feed it to the queens. The bait cocktail is made up of water, vegetable oil, beef liver powder, and xanthan gum, with only 0.5% active ingredient. Most of the bait is food the ants like to eat.
The aerial treatments in Nāhiku will be conducted with the insect growth regulator (IGR) (s)-methoprene (brand name Altosid). The growth regulator in Altosid is like a “birth control” for the queen: her ability to produce new workers will quickly cease, while her existing workers will gradually die of old age after about 3 months. The queens, however, can live well over a year – possibly as long as 2-3 years. However, a queen that cannot reproduce will find herself in a dangerous situation: deprived of the workers that serve, feed and defend her, the queen becomes vulnerable to death by predation or other causes. But in order to prevent the queens from resuming their egg-laying, they must regularly consume the insect growth regulator. Therefore the treatment process must continue until all the queens are gone. Our intent is to apply the aerial treatment for until all the ants are gone, most likely moving to a spot treatment approach after the first year. We will regularly assess the efficacy using survey plots as indicators of our overall success. This will be an iterative, long-term project.
Treatments and related surveys may be delayed by factors such as weather: they are not effective during heavy rain (very light rain is usually okay; no rain is preferable); likewise, certain weather conditions (such as high winds) may create unsafe flying conditions for our helicopter crews. The dates listed on this site, therefore, are approximate and may be adjusted if any treatments get delayed. Please check the website for the most current information.
This video depicts the process followed for each aerial treatment. Treatments will occur every 6 weeks, depending on weather.
- (S)-methoprene degrades rapidly in sunlight, both in water and on inert surfaces. [It] also is metabolized rapidly in soil and does not leach. Thus, it should not persist in soil or contaminate ground water. However, it is our recommendation that you please wait 4 hours before entering an area that has been treated.