Production then ceases and drones remain in the hive until the season is over. In contrast, Africanized drones are produced continuously. At a certain age, they are forced out of the colony and replaced by younger drones. The older Africanized drones, present in ever increasing numbers, frequently drift into European colonies where they outnumber local drones and inhibit their production. Soon they are mating with European queens in the nest and the result is proliferation of Africanized drones by European queens and Africanization of the the colony.
Africanized males have an advantage over European males in part due to sheer numbers.
Because there are so many out, they are present to produce broods, new drones, and swarms earlier in the season than European honey bees. This results in explosive population growth. Another advantage is their intense pursuit of each oppotunity for mating with European queens. A virgin queen ready to mate flies there and from 6-15 matings can take place in rapid succession. The queen then returns to the hive with sufficient sperm for a lifetime of egg-laying.