The decline of the turkey industry was followed by rapid growth in the chicken egg business. Egg production, which began in the 1920s, thrived into the 1970s. In 1970, there were about 50 egg ranches in Ramona. Today, most of the chicken ranches are gone. By 2003, only four remained. A notable exception to the decline is the Pine Hills Egg Ranch, which at 1,100,000 birds is the 58th largest nationally, and the 5th largest in the state of California. The demise of the egg industry was, in part, due to population growth and increased land values. It was also caused by an outbreak of deadly exotic Newcastle's Disease in 1971, which took three years to stem, and another outbreak in late 2002.