The National Park Service is moving ahead with a plan to try to save endangered honeycreeper bird species from avian malaria/NPS

The National Park Service at Haleakalā National Park in Hawaii is moving ahead with a plan aimed at reducing the transmission of avian malaria to threatened and endangered forest birds by suppressing invasive mosquito populations.  

The agency will use an incompatible insect technique (IIT) that consists of repeatedly releasing incompatible male mosquitoes into the wild to reduce the reproductive potential of female mosquitoes in the project area.  The release of these male mosquitos, primarily using drones and occasionally helicopters and ground methods, must be conducted repeatedly over time to achieve and maintain significant suppression of the mosquito populations.      

The approach involves releasing male Culex mosquitoes that carry a naturally occurring bacteria, Wolbachia, that differs from the Wolbachia strain females carry. "The bacteria has kind of hijacked the reproductive system of the mosquitoes," Chris Warren, the park's forest bird program manager, told the Traveler last this year. "If one mosquito that has a type one Wolbachia tries to breed with another mosquito that has a different type, Wolbachia type two, none of those offspring survive. They lay eggs, but the embryos die."

The Hawaiian islands once counted more than 50 species of endemic forest birds, but today there are fewer than 17 species, according to the National Park Service, some with fewer than 500 individuals left

By issuing a Finding of No Significant Impact (FONSI) for the Suppression of Invasive Mosquito Populations to Reduce Transmission of Avian Malaria to Threatened and Endangered Forest Birds on East Maui Environmental Assessment, the park concludes the National Environmental Policy Act process and documents the agency’s decision with the selection of the Proposed Action in the EA that will be implemented.    

The environmental assessment for the project was available for public review between December 6, 2022, and January 23, 2023, with a total of 853 pieces of correspondence received. A summary of the public comments along with agency responses is included in Attachment A of the FONSI document.   

The EA and FONSI are available on the NPS Planning, Environment and Public Comment (PEPC) project site at https://parkplanning.nps.gov/HALE-mosquitounder the “Document List” link on the left side of the page.      

The Hawaiʻi Department of Land and Natural Resources, a cooperating agency on this project, is preparing its own finding covering actions on state-managed and private lands within the project area.