What Are the Life Cycle Stages of a Bee?
Bees are unique insects belonging to the classification Hymenoptera. There are approximately 20,000 distinct species.
In spite of this, development is more or less uniform across species. Bees pass through three stages on the way to adulthood. This is similar to caterpillars that form cocoons and emerge as butterflies.
That’s not to say that the development process is identical for all bees. For social species, such as honeybees, societies are separated by caste.
The adult stage can look different, depending on the caste. Similarly, each species develops at a different pace. One type of bee might mature swiftly whereas another takes a long time to evolve.
Every bee begins life as an egg. Almost all species of bees lay their eggs in protected locations. Social bees care for their eggs, whereas solitary bees do not.
Fertilized eggs grow into females. Unfertilized eggs become males. Solitary bees lay both male and female eggs. Only established social bee colonies produce male eggs.
Honeybee queens lay their eggs in cells inside the beehive. Bumblebee queens brood their eggs in their underground nests. The bumblebee lays her eggs on balls of pollen, taking care to keep them warm.
Parasitic species, such as Psithyrus, lay their eggs in other nests. The larvae are then reared by the workers of the invaded nest.
In contrast, solitary bees don’t have permanent nests or hives. The females lay their eggs in crevices or small underground nests.
The larval stage is the first part of a bee’s life. At this point, bees look more like maggots than the winged insects they will become. This is true of the various species.
Larvae do very little besides eating and molting. Larvae molt as they grow—how often depends on the species and caste. At the end of this stage, the larvae will be up to 1500 times their original size.
Honeybee larvae destined to become workers grow quickly. In only nine days, they are ready to reach the next stage of life.
Queen honeybee larvae grow even faster, pupating after approximately six days. Leafcutter bees, a solitary species, spend roughly two weeks as larvae.
How and where the larvae develop is specific to each species. As an example, social bees living in colonies raise the larvae. The worker caste feeds and cleans the larvae until they become pupae.
Conversely, solitary bees provide supplies for the larvae, rather than caring for them. The freshly hatched larvae will find prepared supplies of pollen and nectar nearby and need to feed themselves.
Once a bee larva is sufficiently grown, it will form a pupa. The larva spins a cocoon around itself, preparing to transform. During the pupal stage, the bees don’t feed.
Solitary bee larvae pupate on their own without assistance. Social bee larvae will receive support from their caretakers. For example, worker honeybees cap the pupating larvae cell with beeswax.
Solitary and social species of bees can be as different as night and day. One of the aspects where this distinction is clearest is when they become adults.
Male Solitary Bees
The males of solitary species often emerge from their pupae ahead of the females. This is to increase the chances of successful mating. The emergence is usually as the temperature rises after the winter, or during the summer months.
Once they’re free of their pupae, the males wait close to the nest for the females to emerge. The males of some species of solitary bees will die shortly after mating. Other males live through the season or longer.
Male Social Bees
Male drones are only born to larger bee colonies. As with solitary bees, they emerge during the late spring or summer. They develop from egg to pupae more rapidly than solitary bees, although taking longer than queen or worker bees.
Drones are a drain on the colony while they stay in the hive. As their sole purpose is to reproduce, they can’t perform other tasks.
They eat large quantities of stored honey, or harass worker bees to be fed. About a week after the drone is out of his pupa, he will begin flying out of the hive.
These are practice flights in preparation for the final mating flight. The males of social species fly far from their hives to breed with unrelated queens to avoid inbreeding.
Drones will die after mating with future queens. Any drones that don’t manage to mate and return to the hive won’t be welcomed. Workers will prevent virgin drones from re-entering the hive. Unable to survive without help or defend themselves, they will die.
Female Solitary Bees
All females from solitary bee species are fertile. When they emerge from their pupae, they are ready to mate. They appear a short time after the males.
The females of certain solitary species will mate more than once. After mating, females start preparing basic nests for their eggs. During this time, they collect the food the larvae will survive off when they hatch. The cycle begins again.
Female Social Bees
Social bee females are either workers or queens. As you may have guessed, these two castes share little in common.
The majority of female larvae will grow into workers. In bee colonies, the workers do all the labor that keeps the beehive up and running. Without worker bees, we wouldn’t have honey.
Workers will never be capable of reproducing. They stay sexually immature for their whole lives.
The jobs a worker bee performs change as she ages. When she has newly emerged from her pupa, she inspects cells and cleans them with her mouthparts. These cells are where the queen will lay her eggs and must be spotless.
At this early stage of adulthood, workers also clean the hive in general. Bee corpses are dragged from the hive and dumped outside it. Similarly, dead invaders, such as moths, are disposed of in the same way.
Next, a worker will graduate to the role of a nurse. In honeybees, this occurs between three and five days later. Nurse workers secrete royal jelly to feed the queen. They are also responsible for raising young bee larvae.
These caretaker-type jobs entail feeding and cleaning. They keep both the queen and larvae free of waste by licking it away and ingesting it.
The workers also aerate the hive by fanning their wings. Additional chores are building and maintaining the hive by producing beeswax.
The worker will eventually start taking practice flights. Once she graduates into the role of forager, she’ll be leaving the nest repeatedly.
Worker bees are the honey-producers of the colony. They gather plant nectar and return it to the hive. Through a process of regurgitation between workers, honey is made. The workers also collect pollen in their pollen baskets. The pollen is returned to the nest to make bee bread to feed larvae.
The average bee colony has a single queen. The queen controls the colony through pheromones she secretes.
Queens have bigger abdomens than workers. This is due to the presence of reproductive organs, particularly the ovaries.
A queen hardly ever leaves the hive as her main function is to lay eggs. She will only leave the hive when new queens are reared.
If the reigning queen sickens or dies, workers know to intervene. They start rearing queen larvae to replace her. New queens are also produced in established colonies.
How Do Bees Reproduce?
When it comes to bee reproduction, females definitely have the advantage. Whether solitary or social, male bees usually don’t live through mating.
Social Bee Reproduction
Remember that for social bees, only queens are fertile. There can be hundreds or thousands of workers in a colony, but none can lay fertilized eggs.
Once a bee colony grows large enough, the time for new queens has come. They are born around the same time as drones.
Workers will feed royal jelly to selected female larvae. By doing so, they guarantee these larvae will develop into queens.
When the new queens are ready to come out of their cells, the original colony will swarm. This means almost all the bees in the colony, including the old queen, will leave the beehive. A small group of workers is left behind for maintenance.
The colony will create a new beehive elsewhere, leaving the existing one for a new queen. Preparation for swarming—such as finding a new home—is done by workers in advance.
Emerging from the pupae as a future queen is a matter of luck. As more than one queen develops at once, there will be competition. The first queen who breaks free of her pupae has the advantage. She will typically attempt to destroy the pupae of her competitors for the hive.
The new queen flies off to a drone congregation site. These are locations where lots of males gather together, waiting for future queens. The queen will make more than one mating flight. In certain species, the queen may mate with up to 18 drones.
Each drone will die after copulating. Part of his endophallus (or penis) will remain inside the queen, which is fatal.
Each time the queen mates with a drone, his sperm is stored in her spermatheca. This is basically a sperm storage pouch.
Drone sperm stays alive in the spermatheca for as long as the queen lives. By the time she is finished mating, she can have millions of viable sperm stored. This is what enables her to lay eggs throughout her life without ever mating again.
Solitary Bee Reproduction
Solitary bees have mating flights, as do social bees. The males of many solitary species die soon after the mating frenzy is over. Others, such as the male carpenter bee, survive the experience.
The females keep sperm stored in their spermatheca. They build small nests to lay their eggs in and add food for the larvae. After laying, the female will leave the eggs to develop unaided.
The mechanics of mating are individual to the species. One type of carpenter bee, Xylocopa varipuncta, has a mating dance that involves scent.
The males have perfume glands to attract females. The males wait in plants, emitting rose-scented chemicals to entice a female downwind.
How Long Do Bees Live on Average?
The lifespan of a bee can be several weeks, months, or years. The species, caste and gender of a bee influence how long he or she will live.
Queen honeybees in the Apis genus can survive for years. Apis mellifera (European honeybee) queens have a lifespan between two and five years on average.
A European honeybee worker’s life is only two to four weeks. If the worker reaches the winter, she can live for months. Male drones live four to eight weeks, and won’t make it to the spring.
Some species are only active seasonally. Bumblebee colonies die off as the summer ends, returning again in the spring. The queens of these species hibernate and lay eggs when the winter is over.
By now, you’re familiar with the basics of the bee life cycle and reproduction. As with any animal or insect. There are many thousands of species of bee out there. A few have been domesticated by us, many more are feral.
As with any animal or insect, it’s important to acknowledge the species diversity. Still, you’re now familiar with the bee life cycle and reproduction basics. Your next step could be picking a species you’re interested in and researching further.