The numbers of mature drones leaving colonies of Africanized and European honey bees were counted after they had been trapped at colony entrances. Two apiaries, each with 10 European and 10 Africanized colonies, were trapped for drones exiting individual colonies on 3 separate days at two week intervals. Africanized colonies maintained far more drones and far more Africanized drones parasitized European colonies than vice versa. These two factors resulted in 91% of the drones leaving colonies in the apiaries being Africanized.
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