State DOA Panel to Consider Importing ‘Incompatible Male’ Mosquitoes to Help Control Wild Populations

The Plant and Animal Advisory Committee of the state Department of Agriculture is looking at importing “incompatible male” mosquitoes as a method of mosquito population control in the islands to help save several native honeycreeper species.

On Thursday, the panel will consider listing three mosquito species already present in Hawai‘i on its restricted species list A, allowing their importation. One of the species, the southern house mosquito, Culex quinquefasciatus, is responsible for sharp declines in populations of many honeycreeper species on the Big Island, Kaua‘i and Maui. All three, including the other two being considered — yellow fever mosquito, Aedes aegypti, and Asian tiger mosquito, Aedes albopictus — are known to carry human diseases.

A collection of agencies and organizations have formed the Birds, Not Mosquitoes partnership, which plans to introduce the birth control method into honeycreeper habitats to try and stop avian malaria from killing the last remaining populations of these birds — some of which have fewer than 100 individuals in the wild and are expected to go extinct in less than two years. Listing the species also will enable the state Department of Health to use a mosquito birth control to reduce populations of mosquitoes of health concern in a safe, targeted manner, without the use of chemical insecticides.

The birth control method uses male mosquitoes, which do not bite, with a strain of a bacterium called Wolbachia that is incompatible with the strain of Wolbachia already found in wild mosquitoes in Hawaiʻi. When these male mosquitoes mate with females in the forest, the eggs do not hatch and the mosquito population size drops.

And despite misinformation circulating on social media, no genes are modified in the mosquito or Wolbachia bacteria.

“It’s disappointing that some people are misinforming others by saying this is using GMOs or GEs,” state Department of Land and Natural Resources Chairwoman Suzanne Case said in a press release. “These are not genetically modified or engineered organisms. The proposed technique does not modify the genes of mosquitoes or Wolbachia. It is similar process to taking antibiotics, then eating probiotics, to replace the existing community of bacteria with a different community within your stomach.”

The mosquito birth control approach is being safely used in 15 different countries, including on the mainland United States, according to the DLNR release.

“The Birds, Not Mosquitoes partnership is guided by the state’s top scientists and researchers, who collectively have many decades of experience studying Hawaiʻi’s forest birds and mosquitoes,” the news release said. “According to Birds, Not Mosquitoes, ‘We need these Wolbachia-incompatible male mosquitoes to be listed so that importation can commence.'”

Landscape-scale control of disease-carrying mosquitoes is considered the most urgent conservation issue in Hawai‘i. A recent U.S. Department of Interior report estimated ‘akikiki on Kaua‘i are likely to go extinct in 2023, and the ʻākohekohe, kiwikiu and ʻakekeʻe soon after that.

“The extinction of the Hawaiian honeycreepers is being driven by exposure to avian diseases transmitted by non-native mosquitoes,” information from the Birds, Not Mosquitoes group notes. “Climate change is allowing non-native, disease-carrying mosquitoes to invade higher elevation forests, which was previously the last disease-free habitat where the honeycreepers were safe.”

The public can weigh in on the proposal through 4 p.m. today.

Submit testimony to Jonathan Ho, Inspection and Compliance Section chief, via email at [email protected] or fax to 808-832-0582. Include “Hawai‘i Plant and Animal Advisory Committee on Proposal to Add Three Mosquito Species to List of Restricted Animals” in the subject line.