On a Wing and a Prayer – The life of a Bumble Bee
While I tend to stick with honeybees, they are not by any means the only family of the vespids which entertain. The bumble bee, also known as the humble bee, is a more primitive bee. While it still forms a colony, the bumble bee is more reminiscent of the wild west than 1984. Every day pushes the bumblebee closer to death, and every flight may tip the balance.
The bumble bee colony begins as a no honeybee can – as a single bee. She is the queen bee, and before she went to sleep in the fall she was called a Gyn. On the first warm day of spring she begins to awaken – her body pulling a chemical miracle in resurrecting itself from stasis. She is groggy at first, but when the sun shines bright enough she begins to flex her wing muscles, producing the familiar “buzz” for which bumblebees are known. This sound is produced by the wing muscles, but not the wings. Bumblebees, like honeybees, can disconnect the wing muscles from the wings themselves and vibrate them to produce enormous heat. That’s precisely what the queen bee does, warming herself to several degrees over ambient temperature.
No honeybee would dare forage in temperatures like this but the bumble bee is built for this climate. Bumblebees are cold weather bees – they possess heat regulation mechanisms and regulate their body temperature much the way mammals do, sometimes being called “The warm blooded insect”. The further north you go the more successful the bumble bee as a pollinator. To survive in this environment the bumble bee is considerably larger. The queen bee is gigantic, and she is fierce, and on this first day of spring she is on a mission.
This mission takes her out of the bark in which she slept away the winter and out across the clearings of the mountain slopes. She stops along the way to suck at the first blooming flowers, and in doing so again sets herself apart from her sisters of the species apis. This flower is too deep for her to reach the nectar – no worry. The bumble bee queen gnaws at the base until she tears open the nectar pocket, and slurps it up. She then seizes the anthers of the flower and vibrates her wing muscles without moving the wings. This act, called buzz pollination, is what makes bumble bees far more efficient pollinators of plants like blueberries. She seizes the pollen shaken loose and packs it onto her legs. From now on she will live like this, hopping from flower to flower, gathering pollen and never traveling further than her crop full of nectar can take her.
She skims over the grass, dropping to the ground from time to time, and moving on. Finally she finds what she is looking for – a mouse nest. The mouse is gone. Where? No one can say, but the mouse isn’t home when she arrives, and If it does come back, it will be in for a nasty surprise. Here, among the fluff and lint of the nest the Queen bumble bee will make her home and found a society. Unlike the queens of clan Apis, which are dependent on their daughters and sisters, the bombus queens are fully self sufficient. They forage for nectar and pollen, draw wax, and lay eggs. Yes, like honeybees bumble bees draw wax, but they do not do so in comb – they create what are known as “nectar pots”, small orange wax pots that resemble a blue berry in size and shape. Into the first pots the queen will deposit what spare nectar she has. A few inches away she begins to build up a odd, jelly bean shaped ball of wax. In this she stuffs the pollen she has gathered, and lays an egg. Bumble bee brood are raised inside these wax envelopes, and kept sealed most of the time. When the larva hatch the queen will occasionally open the wax pod and feed them, then reseal it. By doing so she keeps them warmer. Soon the nest possesses three pots of nectar and seven small lumps of wax, each containing a larva. The queen is the only bee at this point, and she does the work of incubating, using her wing muscles again to warm them. Bumble bees possess a unique mechanism which is designed to transfer heat from the thorax down into the abdomen, better warming the larva. For several days the queen will labor alone, and during that time she will face her gravest threat.
In the short mountain springs the emergence of the bumble bee queens are done all together, thousands awakening at the same time, thousands moving out to found their own private empires. To the earliest to awaken go the choice nests – the mouse holes, the empty insect burrows. Getting such a prime spot is a easy. Keeping it is not. Rival queens have no fear of entering another’s burrow. If another queen is not present, she may steal the nectar, take the pollen, or even worse, lay her own eggs. When the original queen returns it is a fight to the death. Bumble bees possess smooth stingers and a suicidal mindset when defending their hive. They can sting over and over, and their venom is a potent chemical brew made of toxins designed to induce pain and allergic reactions in mammals. Queens possess a curved stinger which is not well suited for stinging mammals. It is very well suited for getting between the body parts of a rival bee and stinging it to death, and that is precisely what will happen. When the dust clears only one bee is alive. She may face a new challenger in an hour or a day. The dead queen will be ignored, and in this the bumble bee again differs. The nest of the honeybee is rigid, uniform, laid out in row in exact widths. The bumble bee nest is chaos in progress. There is no order to the nest. Brood are sometimes near each other, and sometimes far away. Honey, Nectar, there is no rule or reason for their placement. The bees do not clean house or organize. They live in filth.
When the first set of daughters hatch, the bumble bee transforms from a solitary insect into a society. Not a well machined, cooperative one. A society built on size, on bully and push and shove, bite and sting. The queen is far larger than her first daughters, and she’ll keep them in line. Certain bumble bees are known to perform assassination on the queen and usurp nests. Returning workers are beaten into submission and forced to raise the usurper’s children instead. The nest grows, the nectar pots double in number – a tiny amount of honey might be produced, but never more than a few days supply. As the days go on the bees lack of housekeeping draws in worms and other parasites. The bees are ill equipped to deal with their presence, and the colony will simply limp on.
The bumble bee is a master forager, and how it does so is dictated directly by how much nectar is in the nest. In lean times the bumble bees will follow a set of flowers over and over, often getting barely enough nectar to power her wings on to the next flower. Every flight must at least break even or the colony will die. Returning home with an empty crop is a failure tantamount to death, as only the nectar in the nectar pots will keep the colony going. Four days of straight rain can easily starve a colony. Bumble bees combat this by being less picky and foraging in conditions no self respecting honeybee would even leave the cluster for. Bumble bees will take the nectar of almost any flower, the pollen from anywhere. When nectar is in high supply they will explore other flowers, other plants hoping to find sweeter offerings. Many times the workers wind up stranded far from home, without the strength to fly back. A simple sip of sugar water would revive them to return home, but they will not often find it. The best they can hope for is to scale a dandelion and refuel, then take short hops home, arriving with the disgrace of an empty nectar crop.
Back in the nest the queen is now devoted to caring for her daughters and laying more. Her daughters forage but they do not feed her – she will do that for as long as she lives. They will never “defer” to her either – she rules by force. Inside the nest the interactions of the bumble bees show that their society is far from well developed. Of all the social actions known to researchers, only two are friendly - the others read like a rap sheet – “Bite, head butt, pull, chase, sting, pull”. Each bee wanders the nest as though the others do not exist. When they do encounter each other it isn’t for hugs and kisses.
The larger bees forage more. The smaller bees are relegated to brood rearing, caring for the amorphous lumps of wax that contain their sisters. Like Honeybees, worker bumble bees are capable of laying eggs. Likewise since most never mate they can lay only drones. The queen keeps the laying of drones in check though with worker suppression pheromone. As the summer progresses the worker bees get larger and larger – this is leading to the time when the colony will produce the largest of all – the Gyns who will carry on next year. A month or so before time to rear the new queens the queen abruptly ceases suppressing the worker’s urge to lay. Chaos ensues.
If before the nest was made largely of bees which did not notice each other, now it is made of workers who detest each other. They fight constantly for the right to lay eggs, propagating their genes through the drones. Earning the right to lay an egg isn’t enough – they must defend their offspring until they hatch. Honeybees drive the drones from the hive in the fall. Bumble bees do it almost immediately. Throw the bums out seems to be the plan, and they are tossed out of the colony, driven out or killed. Inside the next phase begins.
The queen lays new eggs now, fertilized to produce females, and these will be fed until they are fat giants. These are the Gyns, future queens. As the fall fades they mate with the drones and then fatten themselves on the stores of the colony. When the cold time comes they will burrow away to sleep. In the new defunct colony the queen and her workers will exhaust what little nectar remains and then succumb to the cold.
Never more than a few days from starvation, barely cooperative, often competitive, the bumble bee is like a window into the history of bees in general. In their rough society we can see how the solitary bees became the gregarious bees, and gregarious bees like the orchard mason bee led to these fiefdom outposts known as bumble bee colonies. No doubt the strict hierarchy and cooperation of the honeybee may proves more efficient. Efficiency takes a back seat to entertainment some times. Those times are common in the life of a bumble bee. There every flight is betting their life on the sun and the flowers, on a wing and a prayer.