A state plan to import mosquitoes to help save endangered birds is inching closer to fruition as scientists determine where to release the insects.
Birds Not Mosquitoes is a project by several partners including the state Department of Land and Natural Resources. The effort is aimed at controlling mosquitoes throughout Hawaii and reducing the spread of avian malaria, which threatens critically endangered native bird species such as the ‘akikiki, the ‘akohekohe, the kiwikiu and the ‘akeke‘e.
In order to accomplish this, the state plans to import mosquitoes infected with bacteria known as Wolbachia and release them at certain locations throughout the state.
DLNR spokesman Dan Dennison said via email that mosquito population studies currently are being carried out, with preliminary results expected next week.
He did not specify where those studies are being conducted.
Environmental assessments on Maui and Kauai for the mosquito-release plan are expected to open for public comment next month, Dennison said. However, the DLNR has stated that mosquito populations also are threatening bird species on the Big Island.
The imported mosquitoes would be all males, meaning they would not bite — only female mosquitoes feed on blood — and the Wolbachia bacteria would prevent them from reproducing with local mosquito populations.
When the infected males are released, they will attempt to mate with females, but the bacteria will render them incapable of reproducing.
The short-lived mosquitoes will then die without having produced offspring, which will ultimately reduce the populations over a few generations.
Similar initiatives have been conducted worldwide. In Singapore, for example cases of dengue — a mosquito-transmitted disease — dropped by 88% a year after mosquitoes were released in 2018, according to Singapore’s National Environment Agency.
The Hawaii proposal has been criticized by some residents. At a Friday meeting of the Board of Land and Natural Resources — which discussed a partnership between the DLNR and the American Bird Conservancy to film a half-hour documentary about the project — several residents submitted testimony urging the state to drop the project.
“Adding another invasive species, especially one which can harm humans, is not acceptable for the people of Hawaii!,” wrote Kailua-Kona resident Joanna Weber, echoing comments by several other residents. “Trying to get people to believe that mosquitoes injected with a bacterium which sterilizes eggs are safe and having no studies which prove this, is false propaganda.”
Much of the testimony regarding the project accused the DLNR of having “no plan in place” if the project goes awry, although many also made erroneous claims about the nature of the project.
Some argued that a bacterium that renders mosquitoes sterile could have a similar effect on the endangered birds if it is transferred to them via horizontal gene transfer — a rare process where genetic material can be transmitted from one animal to another without reproduction.
However, Wolbachia does not sterilize mosquitoes, but simply makes it impossible for them to reproduce with another mosquito that is not also infected with the same strain of bacteria.
The Friday meeting did not address the testimony, and the BLNR ultimately approved the video production partnership with the American Bird Conservancy with little discussion.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.