Seasonal Effects on Control Methods for the Great-Tailed Grackle

Efficiency of methods used to control damage to citrus fruit by great-tailed grackles was found to vary considerably from season to season. From April - July, the birds congregated in small breeding colonies where they were susceptible to baiting and poisoning. From August - October, the birds could be baited in to and poisoned at watering sites. Intensive shooting and use of pyrotechnics were also used successfully at this time of year to control damage at groves with high grackle concentrations. From late October - March, birds moved over wide areas each day, and were easily frightened from groves by pyrotechnics and shooting. No single method is available at present to control the entire population or to protect a given grove through all seasons