For the approaching radar experiment, we captured 116 brown-headed cowbirds (58 males and 58 females) using the same decoy traps in the same location. Birds captured for the approaching radar experiment were kept less than one month prior to the experiments. We housed birds in length 2.4 × width 2.4 × height 1.8 m enclosures at the Plum Brook Station in Erie County, Ohio, U.S.A., where the experiment was conducted. Experiment 2 was conducted at a different location from experiments 1A and 1B due to space requirements, so we will not be comparing data from the two experiments. The animals used for both experiments were, however, trapped at the same location. The enclosures for experiment 2 were located inside an aviary with large, barn-style doors that were opened during the day to allow airflow and light, and with screened windows that were always open. Bird in groups of 20 to 50 individuals were provided metal perches, and were given white millet, black oil sunflower, and water ad libitum. Food and water were provided in at least 2 large dishes in each enclosure, and were checked or changed daily. Enclosures were cleaned daily.