In 1989, a sudden invasion of Mediterranean fruit flies (Ceratitis capitata, "medflies") appeared in California and began devastating crops.

[citation needed] Subsequently, three months after "The Breeders" announced the medfly release, the state ended its decade-long Malathion program and sought alternate ways to handle destructive insects.

[4] Largely because of its sunny Mediterranean climate and widespread irrigation, California is the world's fifth largest supplier of food and agriculture commodities.

[11] The 1981 infestation turned into a political crisis and led to the beginning of the state's aerial spraying program in July of that year.

[8] On December 8, 1989, the state retreated from its position that the 12 outbreaks since August each represented "isolated infestations" that could be easily eradicated after a panel of scientific advisers suggested it was not possible.

[24] "State officials have probably noticed an increase as well as an unusual distribution of Medfly infestation in Los Angeles County since March, 1989...

[25][26] The Breeders claimed that it was responsible for the summer release of the medflies as retaliation for the environmental damage caused by the Malathion aerial spraying by the state.

[30] The group promised to make the aerial spraying program politically and financially impossible through the coordinated release of thousands of medflies.

[30] During the course of the investigation, the United States Department of Agriculture attempted to contact The Breeders through a classified ad placed in the Los Angeles Times.

Unless otherwise permitted by law, any person who willfully and knowingly imports into, or who willfully and knowingly transports or ships within, this state, a Mediterranean fruit fly is guilty of a felony.After its repeated sprayings failed to eradicate the medfly threat, California halted its Malathion aerial spraying program in March 1990, three months after the threat from The Breeders was received.

The state instead opted to try the voluntary introduction of millions of radiation-sterilized medflies to interrupt the reproductive cycle and control the population.