In December 2013, The Hawaii Department of Agriculture (HDOA) confirmed that Little Fire Ant (LFA) had spread from Hawaii Island to Oahu and Maui. An inter-agency team led by HDOA was mobilized to respond to this pest emergency. This update is specific to the Oahu based response.
Please find below the latest update or click here to view/download as PDF.
Contact Randy Bartlett, LFA Response Liaison Officer, with any questions related to this update.
Randy Bartlett: Randal.T.Bartlett@hawaii.gov or (808) 870-6443
*Monthly LFA updates will be sent to the full HISC Listserv, to opt-out of the updates, please respond to this email indicating you do not wish to receive them.
For more information, click on the links below:
December 6, 2015 – June 9, 2016
- The Waimanalo and Mililani infestation sites total 12 acres. Surveys will continue on an annual basis for the next two years. Treatments developed by the Hawaii Ant Lab (HAL), were applied in both locations once evidence of LFA was discovered. Monitoring surveys at Mililani Mauka and Waimanalo were conducted in May, 2016.
- In this operational period, the LFA ICS team conducted surveys on priority sites on O`ahu. Surveys continue to be conducted 2-3 days per week, with priorities being nurseries at high risk for inadvertently harboring LFA.
- Staff from HDOA, HAL, and OISC conducted follow up treatments in Waimanalo on the hot spot that was discovered in December 2015. The hot spot was a tall 75 feet gunpowder tree covered in pothos vines. Little fire ants were nesting under the cover of the pothos leaves and between the vines. To effectively treat the tree, we recruited help from an arborist from HECO who could safely climb the tree. The arborist used ropes to pull himself to the top of the tree to treat areas where LFA was nesting in the upper canopy. Initial treatments involved killing the pothos vines with an herbicide, and applying the ant insecticide bait under the canopy of the leaves.
- On May 25, 2016, we treated the hot spot in the Waimanalo treatment area for the fifth and final time. On the final two treatments, the arborist checked for ants in the upper canopy and found no LFA. On the final treatment the dead vines were removed from the tree as a precaution to prevent a re-infestation. A survey of the perimeter of the tall tree was negative for LFA, and a comprehensive surveys conducted in March 2016 of the entire treatment area covering six acres in Waimanalo was negative for LFA.
- Approximately 1,300 vials were distributed. No LFA positive samples were obtained in the surveyed area.
- The entire area – including commercial nurseries - will continue to be monitored every 6 months for at least the next 2 years – if no further LFA are detected on site. The next monitoring survey is scheduled for early November, 2016.
- Other area nurseries surveyed: The last positive detection was at the end of October, 2015. Monthly treatments will be continued.
- The Mililani Mauka comprehensive monitoring survey was conducted on Wednesday, June 9, 2016:
- 1,500 vials were distributed. No LFA were detected. 22 properties, green belt, and common areas along roads all sampled negative for LFA. HDOA is currently using 50 vials/property distribution density. The density/number of vials used may decrease moving forward pending determination by HDOA and HAL. The next monitoring survey is scheduled for early November, 2016.
- Hawaii Ant Lab:
- The HDOA will fund the 2 person HAL crew on O`ahu for another year in order to continue the monitoring effort.
- The Oahu Invasive Species Committee (OISC) will continue vegetation control to keep the Waimanalo site clear for future surveys.
- The Mililani Mauka site continues to be maintained by the Mililani Town Association in cooperation with the HDOA PPC.
- Instagram accounts were established at:
- Little fact about Little Fire Ants: For more information about LFA, visit:
This report uses the best information available at the time of writing and is not an official record of the project. Its purpose is to update partner agencies and concerned individuals about project progress. Questions regarding information in the report can be addressed by calling the incident command post at (808) 973-9528. Mahalo.