Sterile Insect Technique

The sterile insect technique, or SIT, is a method of biological insect control in which overwhelming numbers of sterile insects, preferentially males, are released into the wild. The sterile males compete with fertile wild males to mate with wild females; a female that mates with a sterile male produces no offspring, which reduces the size of the next generation, and because the sterile insects cannot self-replicate they cannot establish themselves in the environment. Repeated releases over areas with low pest densities can suppress or eliminate a population, though dense populations typically need initial suppression before sterile insects are deployed. The technique has been used to eradicate the screw-worm fly from North and Central America and to control fruit flies including the Mediterranean and Mexican fruit flies; sterilization relies on x-ray irradiation of the insects' reproductive cells, and SIT does not involve releasing insects modified through genetic engineering or introduce any non-native species into the ecosystem.