Two Little Fire Ant Infestations Under Treatment on Maui

Multi-agency efforts continue in the eradication of little fire ants (LFA) as several new infestations have been detected on Oʻahu and Kauaʻi. There are currently seven sites being treated on Oʻahu, two on Maui and one on Kauaʻi for infestation of LFA. October is Stop the Ant Month which reminds residents to be aware and check for LFA in their homes and yards.

The two Maui infestations include:

Wailuku, Maui: 

• Reported April 3, 2019 – Resident submitted ant samples to HDOA
• Treatment zone 2.0 acres, residential area, 18 properties involved
• Treatment began April 30, 2019
• Participating partners: HDOA, Maui Invasive Species Committee (MISC)

Waiheʻe, Maui

• Reported September 10, 2019 – Landscaper submitted ant sample to MISC
• Treatment zone approximately 5 acres, 3 properties involved
• Treatment will begin when surveys are complete
• Participating partners: HDOA, MISC

On Oʻahu, neighborhoods in Kaneʻohe, Ahuimanu, Lanikai, Kualoa, Makiki Heights, Pauoa, and Laie are currently being treated; and Kilauea on Kauaʻi is also being treated for infestations.

Kaneʻohe, Oʻahu

• Reported December 19, 2018 – Samples submitted to HAL
• Treatment zone 2 acres; 11 properties involved
• Treatment began January 2019; survey in July 2019 found no LFA
• Participating partners: HDOA, HAL

Ahuimanu, Oʻahu

• Reported January 25, 2019 – Samples submitted by resident to Oʻahu Invasive Species Committee (OISC)
• Treatment zone 2 acres; 12 properties involved
• Treatment began March 2019
• Participating partners: HDOA, HAL, OISC

Lanikai, Oʻahu

• Reported June 13, 2019 – Resident submitted ant samples to HAL.
• Treatment zone < 2 acres; 6 properties involved
• Treatment began July 17, 2019
• Participating partners: HDOA, HAL

Kualoa, Oʻahu

• Reported May 8, 2019 – Kualoa staff submitted ant samples to OISC.
• Treatment zone 20 acres; pastures, natural areas, unpaved roadways
• Treatment began September 16, 2019
• Participating Partners: Kualoa Ranch, HAL, HDOA, GCAPS, OISC, Oʻahu Army National Resource Program (OANRP), U.S. Fish and Wildlife Service (USFWS),

Makiki Heights, Oʻahu

• Reported July 23, 2019 – Resident submitted ant samples to HAL – Oʻahu
• Treatment zone approximately 5 acres; 18 properties involved
• Treatment began October 9, 2019
• Participating partners: HDOA, HAL

Pauoa, Oʻahu

• Reported August 30, 2019 – Resident submitted ant samples to HDOA/HAL
• Delimiting surveys currently being conducted on approximately 2 acres and 8 properties involved
• Treatment will begin when surveys are complete
• Participating partners: HDOA, HAL

Laie, Oʻahu

• Reported October 7, 2019
• Delimiting surveys currently being conducted
• Participating partners: HDOA, HAL, GCAPS, OISC, OANRP, USFWLS

Kilauea, Kauaʻi

• Reported September 6, 2019 – ant sample turned in to HDOA by pest control operator
• Treatment zone 2.5 acres, 13 properties involved
• Started treatment October 21, 2019
• Participating partners: HDOA, Kauaʻi Invasive Species Committee

“The increasing number of LFA detections in previously uninfested areas should be cause for concern for everyone,” said Phyllis Shimabukuro-Geiser, chairperson of the Hawaiʻi Board of Agriculture. “It is imperative that residents check their properties periodically to prevent the spread of infestations in their neighborhoods.”

The Hawaiʻi Department of Agriculture (HDOA), Hawaiʻi Ant Lab (HAL) and partner agencies, including the Hawaiʻi Invasive Species Council, the Invasive Species Committees on Oʻahu, Kauaʻi, and Maui County and the Coordinating Group on Alien Pest Species (CGAPS) have been asking residents on Oʻahu, Kauaʻi and Maui County to survey their properties for LFA by using a little peanut butter on a chopstick and leaving them in several areas for about one hour. Any ants collected should be put in a sealable plastic bag, placed in the freezer for at least 24 hours and dropped off or mailed to any HDOA office. An informational flyer may be downloaded HERE.

In addition, the Department of Land and Natural Resources (DLNR) has produced a three-minute video, “How to Test for LFA,” (posted below) which shows the step-by-step procedure for testing for LFA.

LFA was first detected in the state on Hawaiʻi Island in 1999. However, by time it was found, the ants were widely disbursed on the island and no treatment protocol existed for eradication. The HAL was then established to research best method of eradication and control of LFA. The treatment plans developed by HAL and HDOA entomologists have been very successful in eradicating new infestations. The protocol uses several types of pesticides and bait formulas applied on a six-week interval for a total of eight treatments.

Originally from South America, LFA is considered among the world’s worst invasive species. LFA are tiny ants, measuring 1/16th inch long, and pale orange in color. LFA move slowly, unlike the tropical fire ant, which is established in Hawaiʻi, can move quickly, and is much larger with a larger head in proportion to its body. LFA can produce painful stings and large red welts and may cause blindness in pets. They can build up very large colonies on the ground, in trees and other vegetation, and inside buildings and homes and completely overrun a property.

Suspected invasive species should be reported to the state’s toll-free PEST HOTLINE – 643-PEST (7378).