Agriculture Board endorses plan to import millions of mosquitoes to save Hawaii’s imperiled birds

The state Board of Agriculture on Tuesday gave the green light to the release of tens of millions of mosquitoes into the wild as part of a plan to help save Hawaii’s endangered forest birds.

The board voted to list the southern house mosquito (Culex quinquefasciatus) as a restricted species, allowing the state Board of Land and Natural Resources to import the insect, and to authorize a permit for their release.

The Agriculture Board also approved a similar request by the state Department of Health, which asked to list the southern house mosquito as well as the Asian tiger mosquito (Aedes albopictus) and the yellow fever mosquito (Aedes aegypti). The action gives the department the ability to import any of those mosquitoes for use in fighting a mosquito-borne disease outbreak.

Mosquitoes carrying avian malaria are the biggest threat to the birds, according to scientists. With climate change, the mosquitoes are moving higher into the mountains, and more birds are dying as their habitat shrinks.

The 9-0 vote — with DLNR Chair Suzanne Case abstaining — came despite written testimony from nearly 100 people opposing the action, many of them fearful of unintended consequences and calling for long-term studies to learn the ultimate effects of releasing the mosquitoes.

But scientists told board members the technique to be used in the project has been thoroughly vetted, approved for use by federal authorities and used successfully on the mainland and elsewhere.

Cynthia King, state Division of Forestry and Wildlife entomologist, said the environmental assessments now being written for the initial releases in remote areas of Maui and Kauai should be completed by August or September, after which the project can move forward.

The first releases are aimed at saving two of Hawaii’s most endangered native birds: the akikiki, with an estimated 45 individuals remaining in the wild on Kauai, and the kiwikiu, with 135 left in the wild on Maui. Scientists say these species could go extinct in less than two years without some kind of help.

The effort is being planned by a group of state and federal agencies and private conservation groups that have coalesced under the name Birds, Not Mosquitoes.

The state in May announced a $14 million influx of federal funds that will go toward further development of the mosquito control effort.

The group’s plan involves transferring a naturally occurring “birth control” bacteria to mosquitoes in a mainland lab. Only male mosquitoes, which don’t bite birds or people and, therefore, don’t transmit diseases, would be released into the wild. These male mosquitoes would mate with wild female mosquitoes, whose eggs would not hatch.

Officials said mosquito eggs from Hawaii already have been sent to a mainland lab.

Those mosquitoes, according to the plan, will be crossbred with mosquitoes with a different strain of Wolbachia, a type of bacteria found across the state. Once those mosquitoes take up the new strain, they will be crossbred with a separate population of mosquitoes with Hawaii origins over seven generations, ensuring the genetics of the introduced mosquitoes will have more than 99% similarity with the wild mosquito populations in Hawaii.

Many of those who wrote to oppose the effort condemned the use of genetically modified or engineered mosquitoes.

King countered that both the Environmental Protection Agency and the U.S. Food and Drug Administration, after extensive review, have agreed the technique is not genetic modification.

“It really is just using this naturally occurring bacteria that a mosquito can normally carry and exposing it to a different strain,” she said. “It is the same as us eating a container of yogurt and having the potential for the bacteria strains in the yogurt help with our indigestion.”

One caller to the virtual meeting offered testimony against the project, pointing to a study conducted in Singapore that suggested the Wolbachia bacteria might transfer to other organisms over time.

But King said the strains of bacteria to be imported to Hawaii are already found in mosquitoes that have been here for 200 years, and that transfer could have already happened but hasn’t.

She said there will be severe consequences for Hawaii’s forest birds if officials do not act soon.

“They do not have 200 years. They do not have 100 years,” she said. “They have less than five years in some cases, and that is what really is motivating DLNR to propose this as a tool to save them.”

A University of Hawaii at Hilo study published in April found that a handful of Hawaiian honeycreepers are heading toward extinction in the next few years unless they get a helping hand.