The article explains that as the New World screwworm spreads north from Mexico, California researchers are urging livestock producers to prepare before the parasite reaches the state. Alec Gerry advises ranchers to learn how to recognize screwworm infestations and protect animals, noting that the pest can enter even small wounds and quickly cause severe tissue damage. Amy Murillo and Gerry are leading a California surveillance effort that uses specialized traps in Southern California counties to detect the pest as early as possible, supported by state funding. If a suspicious fly is found, it will be sent to a USDA laboratory for genetic testing and confirmation. The researchers emphasize that early detection, producer education, and ongoing monitoring are essential to preventing major impacts on California's livestock industry and wildlife.