Western Honey Bee - Biology, Life Cycle

Biology, Life Cycle

In the temperate zone, honey bees survive winter as a colony, and the queen begins egg laying in mid to late winter, to prepare for spring. This is most likely triggered by longer day length. She is the only fertile female, and deposits all the eggs from which the other bees are produced. Except for a brief mating period when she may make several flights to mate with drones, or if she leaves in later life with a swarm to establish a new colony, the queen rarely leaves the hive after the larvae have become full-grown bees. The queen deposits each egg in a cell prepared by the worker bees. The egg hatches into a small larva which is fed by 'nurse' bees (worker bees which maintain the interior of the colony). After about a week, the larva is sealed up in its cell by the nurse bees and begins the pupal stage. After another week, it will emerge an adult bee.

For the first 10 days of their lives, the female worker bees clean the hive and feed the larvae. After this, they begin building comb cells. On days 16 through 20, a worker receives nectar and pollen from older workers and stores it. After the 20th day, a worker leaves the hive and spends the remainder of its life as a forager. The population of a healthy hive in mid-summer can average between 40,000 and 80,000 bees.

The larvae and pupae in a frame of honeycomb are referred to as frames of brood and are often sold (with adhering bees) by beekeepers to other beekeepers to start new beehives.

Both workers and queens are fed "royal jelly" during the first three days of the larval stage. Then workers are switched to a diet of pollen and nectar or diluted honey, while those intended for queens will continue to receive royal jelly. This causes the larva to develop to the pupa stage more quickly, while being also larger and fully developed sexually. Queen breeders consider good nutrition during the larval stage to be of critical importance to the quality of the queens raised, with good genetics and sufficient number of matings also being factors. During the larval and pupal stages, various parasites can attack the pupa/larva and destroy or damage it.

Queens are not raised in the typical horizontal brood cells of the honeycomb. The typical queen cell is specially constructed to be much larger, and has a vertical orientation. However, should the workers sense the old queen is weakening, they will produce emergency cells known as supersedure cells. These cells are made from a cell with an egg or very young larva. These cells protrude from the comb. As the queen finishes her larval feeding, and pupates, she moves into a head downward position, from which she will later chew her way out of the cell. At pupation, the workers cap or seal the cell. Just prior to emerging from their cells, young queens can often be heard "piping". The queen makes this noise to prove her space. If successful, this piping seems to have a calming and harmonizing effect on the worker bees.

Worker bees are infertile females, but in some circumstances, generally only in times of severe stress or with the loss or injury or declining health of the queen, they may lay infertile eggs, and in some subspecies these eggs may actually be fertile. However, since the worker bees are 'imperfect' females (not fully sexually developed), they do not mate with drones. Any fertile eggs they lay would be haploid, having only the genetic contribution of their mother, and in honey bees these haploid eggs will always develop into drones. Worker bees also secrete the wax used to build the hive, clean and maintain the hive, raise the young, guard the hive and forage for nectar and pollen.

In honey bees, the worker bees have a modified ovipositor called a stinger with which they can sting to defend the hive, but unlike other bees of any other genus (and even unlike the queens of their own species), the stinger is barbed. Contrary to popular belief, the bee will not always die soon after stinging: this misconception is based on the fact that a bee will usually die after stinging a human or other mammal. The sting and associated venom sac are modified so as to pull free of the body once lodged (autotomy), and the sting apparatus has its own musculature and ganglion which allow it to keep delivering venom once detached. This complex apparatus, including the barbs on the sting, is presumed to have evolved specifically in response to predation by vertebrates, as the barbs do not function (and the sting apparatus does not detach) unless the sting is embedded in elastic material. Even then, the barbs do not always "catch", so a bee may occasionally pull the sting free and either fly off unharmed, or sting again.