Drones signal the beginning of swarm season

If you happen to see a swarm of honeybees the best thing to do is immediately contact your local bee association.
Drones signal the beginning of swarm season

Nothing signals the approach of swarm season more reliably than the appearance of drones in the apiary.

The drones are the males in the hive and a colony won’t swarm if the new queen has no way to mate, but once drones are abundant, mating can occur and a populous colony may decide to split and form a swarm.

When conditions are right in the hive, the old queen or a young newly-hatched queen leaves with many of the workers in a huge cloud of bees.

A swarm of honey bees may contain from 12,000 to 30,000 bees and is an instinctive and natural part of the annual reproduction lifecycle of a honey bee colony.

It provides the mechanism for the colony to reproduce itself.

Swarms usually emerge from their colonies between 10am and 2pm on warm sunny days.

They have filled up with honey and are searching for a new home and so are normally docile and not interested in humans.

The swarm of honey bees will then all temporarily cluster, at one location, such as on a branch of a tree or bush.

The cluster of bees range in size from the size of a large grapefruit to basketball size and sometimes larger. Scout bees are then sent out in search of a suitable home, such as a hole in a tree or a building.

The existence of a swarm can take a few hours to several days, until a suitable cavity is found.

Then the swarm moves as a group to that new site.

In late May and June, a hive of honey bees will have three types of honeybees in it; one queen, a couple of thousand male drones (about 15% of the population of the hive) and tens of thousands of female workers.

The workers and queen overlie the winter but it’s not until late spring that the queen starts laying drone eggs in special cavities called cells that are larger than worker cells.

When examining a hive these drone cells can often be seen near the sides of the frame or on the edges of the brood nest.

The workers prepare the cells and the queen lays unfertilised eggs in them.

Although this is hard for us to grasp, the queen can decide when and where to lay these eggs and she decides when to fertilise them.

Unfertilised eggs always develop into drones, and fertilised eggs can become either workers or new queens. How she makes this decision still eludes scientists.

After being born, every young queen goes on a mating flight to get mated with the flying drones.

She stores the sperm she collects from multiple matings during the first two weeks of life for the rest of her life, using it up bit by bit as she lays eggs.

So it if the queen decides to add sperm to an egg, it will produce a female; if she withholds sperm, the egg will produce a male.

That would appear to give the queen control over the sex of her offspring.

However, the dogma among entomologists is that workers control the type of eggs the queen lays.

The workers build the cells, in which the queen will lay her eggs.

A queen will lay an unfertilised egg in a particular cell only if the cell is big enough to accommodate a male larva, which is bigger than a female one.

So by controlling how many cells they build of each size, the workers can limit how many male offspring the queen produces.

Despite these constraints, the queen can still tip the gender balance of the hive. This was proven by Michigan State University about 10 years ago when they confined queens inside their hives in specially built cages.

Each cage was placed so that the queen could not reach the large cells where she could lay drone eggs but only the small cells where she could lay worker eggs. After four days, the cage was removed and the queen allowed to roam free in the hive, which had ample empty cells of both sizes.

The queen then sought out the larger cells and, on average, laid nearly three times as many drone eggs as usual, apparently making up for the skewed hive gender ratio that resulted from her imprisonment.

It seems then that the workers and the queen clearly share control of honey bee demographics.

It’s a kind of checks-and- balances government inside the hive.

The queen’s ability to make ‘her own decisions’ adds a new layer of complexity to life in the hive.

Is she remembering how many eggs she has laid, can she sense how much sperm she has used, or is there some other mechanism telling her how many drone larvae are in the cells?

The drone honey bees look very different than the workers.

They are bigger, blocky in shape, and have huge eyes that almost meet at the top of their heads.

These very sensitive eyes help the drones spot queens flying overhead when they are trying to mate.

Flying drones meet in an area above the ground called a “drone congregation area,” and wait for new queens.

Drones don’t have stingers, so they can’t defend the hive, though they can help the nursery worker bees maintain the temperature of the brood nest.

They generally don’t feed themselves, but beg food from workers.

Towards autumn when the days are getting shorter and the nights are cooler, the workers stop feeding the drones.

When they get weak enough, the workers force them out of the hive where they will starve and die.

Just as the appearance of drones in the spring signals the start of the reproductive season, drones struggling with workers at the hive entrance signals the coming of autumn.

* If you happen to see a swarm of honeybees the best thing to do is immediately contact your local bee association and the secretary should be able to signpost you to the nearest beekeeper.

Association details are available on the The Federation of Irish Beekeepers’ Associations website at: www.irishbeekeeping.ie/index.php/find-an-association

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