Direct economic losses caused by birds amounted to between $3.60 and $8.40 per day, or between $564 and $1,296 for the five winter months of this study involving a 20-acre desert feedlot occupied daily by between 10,000 and 12,000 head of cattle. The total ecological and environmental impact of the birds—including beneficial habits elsewhere at other times of the year—must be considered before control methods are undertaken.