The Department of Land and Natural Resources (DLNR) has initiated a novel approach to protect Kaua’i’s endangered forest birds by releasing mosquitoes. The technique, known as Incompatible Insect Technique (IIT), has been previously employed worldwide to combat human malaria but is being used for the first time on Kaua’i to control malaria-carrying mosquitoes.
According to Crampton, “It is a tried and true and safe technique that has been used hundreds of times.” The mosquitoes are transported from California and released weekly in biodegradable cones from helicopters. This method aims to disrupt the reproductive cycle of wild female mosquitoes by ensuring they encounter incompatible males. “We do this twice a week to ensure there’s a very, very high likelihood that a wild female will encounter one of the incompatible males. We’re really trying to interrupt the reproductive cycle,” Crampton explained.
Justin Hite from DLNR’s Division of Forestry and Wildlife expressed optimism about the project, which he hopes will benefit species like the ‘akikiki and the ‘akeke’e. “We hope this really moves the needle for these species,” Hite stated after observing mosquito releases.
In addition to IIT, an integrated pest management strategy includes using BTi larvicide, targeting mosquito larvae. BTi has been applied on Alakaʻi both on the ground and via helicopter for over nine years. Crampton noted that combining IIT with BTi should enhance effectiveness: “So, the idea is the BTi reduces populations of adult mosquitoes to begin with, making it more likely that females will encounter one of these incompatible males.”
Conservation breeding programs provide insurance for critically endangered birds’ survival. Once IIT and BTi have been in use over prime bird habitats for a year or more, there is hope that conservation program birds or their offspring can be reintroduced into their natural environment.
