Agriculture Reference
In-Depth Information
Drones and mating
The drone is optimized for mating and, to do this to best effect, he needs to be able to
fly extremely fast (his flight muscles and wing size are larger than worker bees'), to have
extremely sharp vision and an extraordinary array of sense organs designed to respond
to queen and other drone pheromones over large distances. For example, a queen bee
has around 3,000-4,000 eye facets in her compound eye; a worker bee has up to
6,900; but a drone has up to 8,600. A queen bee has some 1,600 antennal plate organs
(sensory organs); the worker has around 3,000, and the drone has an amazing 30,000.
And it is these receptors that have been studied closely to find out how a drone finds a
queen in the air and, sure enough, a research team in the USA has recently identified
an odorant receptor that allows male drones to find a queen in flight. The receptor on
the male antennae can detect an available queen up to 60 m (195 ft) away. The drone
detects the queen substance pheromone, and this is the first time an odorant receptor
has been linked to a specific pheromone in honey-bees.
Queen substance pheromone
The 'queen substance' (or 'queen retinue pheromone') was first identified decades ago,
but scientists have only recently begun to understand its structure and role in the hive.
This pheromone is a primary source of the queen's ability to influence behaviour in
the hive. It is made up of eight components, one of which - 9-oxo-2-decenoic acid (9-
ODA) - attracts the drones during mating flights. (It also draws workers to the queen
and retards their reproductive growth, which means that the lack of a queen can lead to
the presence of laying workers; we deal with this problem in Chapter 8.)
After mating
In the sense that the drone is a vital link in the reproductive chain, the colony could
not do without him, but he has few if any other tasks. During the autumn and winter
periods or other periods of dearth when mating cannot take place or other survival
factors take priority for the colony, the workers will therefore destroy drone brood and
drag out drones and kill them or refuse their readmittance to the hive.
The number of drones in a colony at the height of the season will be in the hundreds
only, perhaps at most around a thousand. The drone is fed by workers until he is around
seven days old, and he remains in the hive until around 12-13 days old when he is
