Mating Behaviours
Beowulf Cooper identifies three types of mating behaviour for the black bee:
1. Apiary Vicinity Mating
2. Local Assembly Mating
3. Distant Assembly Mating
In my own experience I have only found evidence of the first two of these.
Apiary Vicinity Mating (AVM)
I have often seen a hive attacked by drones. Not literally, but the hive apparently comes under siege by many drones. I have assumed that they are attracted to a colony with a virgin queen and that the queen is ready to mate. The drones arrive at the hive to escort the queen on her mating flight. As a preliminary to the emergence of the virgin queen, some bees will appear around the entrance in a very agitated state. The queen will emerge also agitated, will run around before taking off to be mated. She will return within 30 minutes with the mating sign.
I have only once seen the queen coupled with a drone flying slowly around the apiary just over head height. I assumed they settled somewhere but was unable to find the spot.
Local Assembly Mating
In mid July last year I was attracted to the apiary hearing a loud buzz. I assumed that a swarm had emerged and was preparing to take it. However, there was no swarm but the loud buzzing continued. This was my first experience of a drone assembly in the vicinity of the apiary. I assumed at the time that a queen was up flying with the drones being mated but was not fortunate enough to see her return to her hive.
Distant Assembly Mating
In a very interesting
paper on the black bee published in 2005 [9] the authors used DNA microsatellite markers to investigate the distance traveled by drones on mating flights in two adjacent but isolated valleys (Eden and Hope) in the Peak District, Derbyshire, England. It was found that "90 % of the offspring resulted from mating distances of 7.5 km (4.6 miles) or less, and 50% of the offspring from mating distances of 2.5 km (1.5 miles) or less". What is perhaps worthy of noting in terms of the mating behaviour of the black bee it was found that 20% of all mating were between queens and drone from the same apiary (Apiary Vicinity Mating/Local Assembly Mating).
The maximum mating distance observed for one queen was 15 km (9.3 miles).
It is an interesting exercise to look on a map to find the area from which a foreign drone could be attracted to one's own apiary.
This
link brings up a map onto which a circle of given radius is drawn. (Two circles may be drawn to look at any overlap between apiaries). Drag the map to your apiary and just follow the instructions given below the map.
The ability of drones to fly relatively long distances to mate might explain one surprising observation from a hive with a newly mated queen.
The image on the left shows some of the bees that this new queen was producing. Most were black as might be expected but some were seen with a very orange tergite resembling a Buckfast bee. I am not aware of any beekeeper in my immediate area keeping Buckfast bees, so could the queen have mated with a Buckfast drone which had flown into the area from a distance?
Polyandry
The multiple mating of the queen
is directly related to the fitness of the colony. The greater the number of matings the greater is the genetic viability among the queen's worker offspring. (This is discussed in Genetics 2C in the menu above).
In the same study cited above, it was found that the average number of drones with which a queen mated was 10.2; the lowest number being 5 and the highest 14.
Thus on average each colony contained 20 subsets of worker bees. Each subset containing its own genetic mix.