Incompatible Insect Technique
This project uses the Wolbachia-incompatible male mosquito through the Incompatible Insect Technique (IIT) to suppress mosquito populations. Wolbachia is a common, naturally occurring bacteria in nearly half of the world's insect species, including native Hawaiian insects.
This approach takes advantage of the fact that mosquitoes with different, incompatible strains of Wolbachia can’t produce viable offspring. Male mosquitoes with one strain of Wolbachia can only reproduce with females with a compatible strain of Wolbachia. Conversely, males with one strain of Wolbachia cannot produce viable offspring with females that have a different, incompatible strain of Wolbachia.
For this project, egg rafts of the southern house mosquito were collected from Hawaiʻi and sent to a facility on the U.S. continent. Researchers transferred an incompatible strain of Wolbachia into the mosquitoes in a laboratory setting and then reared large numbers of them. Once separated by sex, only male mosquitoes (which do not bite) are transported from the rearing facility and released back into mosquito breeding grounds in Hawaiʻi to mate with wild females. The development and production of incompatible males is done in a facility on the U.S. continent because Hawaiʻi doesn’t currently have a facility for producing large amounts of incompatible male mosquitoes.
When the released Wolbachia-incompatible male mosquitoes mate with wild females, the females lay eggs that never hatch. With consecutive releases, mosquito populations decrease because no new generations are produced.
Fewer mosquitoes are great for our birds! The decrease in mosquito populations means that there will be fewer mosquitoes that are able to transmit fatal avian malaria to our endangered honeycreepers.
Watch this video for more information about how the technique works.