A Night in the Life of a Working Mother

It is spring but you wouldn’t know it judging by the temperature. Here in such northern latitudes, Ellesmere Island to be more precise, winters are long and brutal; spring and summer last no longer than a sigh. So, this morning the air is crisp, and I would call it bitter, as I am not used to this weather. The frost covered grass crunches under your foot with each step you take. However, there are flowers all around. A carpet of small flowers is growing hastily so that the plants can complete their cycle before winter arrives. But, why are there so many flowers? Who visits them and pollinates them? Certainly not honeybees. They can’t endure this climate. Bumblebees! that is who. They are hardy and well prepared for such harsh climate.

Let us look at one in particular, Ms. Bombus, a plump and fuzzy little lady that has been very busy for the past few weeks. She has found an abandoned vole’s nest; has redecorated it inside making it suitable for her coming family. She has prepared several enormous wax pots full of nectar or pollen. They are enormous compared to her size; to us they are nothing but thimblefuls. Then she has laid six little eggs that, by now, have turned into squirmy, hungry babies that she feeds several times a day, alternating with trips in search of more food.

Tonight, she is very concerned. She doesn’t need to watch the weather report on television in order to know that a cold snap is coming, colder than usual, that is. Bumblebees that live in other regions can wait to start a family until the weather is balmier but she doesn’t have that luxury. The growing season is too short so she had to speed things up despite the risk involved. The coming cold could kill her precious babies.

Fortunately she is well prepared to take care of them. She is covered with a thick and fluffy fur all over most of her body. On her belly she has a bare patch that reminds us of the brooding patch that many birds have when they are raising a family. So, just like a mother bird she lays spread eagled on top of her brood and thanks to her thick fur coat she is able to keep them warm for a while. Soon this is not enough because the temperature keeps dropping, so she begins to vibrate her strongest muscles, the flying muscles of her chest. This time she isn’t flying, just generating heat that is transmitted to the babies beneath her. She keeps shivering this way hour after hour, as long as needed. This effort uses up lots of energy and makes her very hungry. With great foresight she had placed her nursery and herself just on front of one of the wax pots brimming with honey, an excellent fuel, and she periodically drinks from it.

The night goes on, grueling and relentless, until finally the sun begins to shine and to warm up the fields. Only then can Ms. Bombus relax and rest, still covering her precious family a little longer. Later on, when it is warm enough, she moves away from the babies and with one final tender look at her wiggly and happy gang she heads for the front door. Bleary eyed and sore muscled, she faces her day job, a full day of gathering badly needed provisions for her brood and for herself.

Bumble bee life cycle

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© Beatriz Moisset. 2012

Floral Emissaries

The raising sun turns the meadow into multicolored blankets of sparkling dewdrops. One flower stretches its petals lazily; it is still too early. She sets the table with a scented tablecloth, arranges bowls brimming with nectar; the anthers full of pollen have burst open exposing their golden dusty treasure and she wonders: Will the visitors come? Sadly, the weather turns bitter and windy and the sun finally refuses altogether to come from behind the clouds; wrong weather for winged visitors.

The next morning the wind is gone; the sun begins to warm the land and melt the dew drops so our flower feels her hopes rise. She is not alone; many others show their charms letting their aroma float in the breeze with the same hope of attracting guests. Better this way, so the callers can carry love messages between them.

The sun keeps climbing and finally a buzzing sound announces the arrival of one of the anxiously awaited visitors. A shiny metallic green bee stops briefly at a nearby blossom and then comes to her. Wisely, she has painted darker lines that point the way to the hidden nectar; thus the guest has no trouble finding it and drinks it avidly and briefly. The cunning flower has prepared just enough nectar to attract a visitor, but not so much that the bee would become satiated and return home without further visits. The guest brushes accidentally against the anthers and some pollen sticks to its hairy body. This is no accident; the flower has placed things just right where she wants them; now her pollen will travel to other flowers.

A parade of winged travelers follows on the next few days. Not all of them are shiny bees, there are others: fuzzy bumblebees, flower flies, a few flashy butterflies and moths and even a beetle.

Finally the pollen is all gone and the anthers begin to wilt. But the flower isn’t done yet because deep inside the ovary, at the very heart of the blossom, sit the future seeds. Now the ovary begins to bulge and its tip at the end of a little tube, the stigma, glistens with a sticky substance meant to receive the pollen from other flowers, the love messages brought unwittingly by the visitors. So the flower keeps inviting guests with its nectar and hoping that they come loaded with other pollens and ready to leave some of their cargo behind. Pretty soon the grains that were left on the stigma will begin to make their way toward the carefully sheltered future seeds. Only now is the flower satisfied of a mission accomplished and only now she allows the colors to fade and the scent to disappear; the petals shrivel and will soon fall to the ground.

Only the ovary remains with its seeds and with all the promises of generations to come. Later on it will become a juicy berry that will attract another kind of visitors, hungry birds and other small animals; they will carry the seeds, adventurous explorers, to farther meadows, to a new life away from the mother plant. But, that is another story.



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© Beatriz Moisset. 2012

For the Love of Flowers

Andrena, the bee, was sleeping her long slumber, comfortably inside her underground refuge, when something began to arouse her. She had been born the previous spring inside this cozy underground cell and she had grown well nourished by the mixture of flower’s nectar and pollen that her provident mother had stored. Later on, like the sleeping beauty, she had fallen into a deep trance for many months. But now it was spring and the soil was beginning to warm up. Did the warmth wake her up? Or was it some mysterious internal calendar? Suddenly that cozy cell that had been her nursery, her castle, her realm, her whole universe through the hot months of summer and cold ones of winter had become an intolerable prison. She had to get out.


Moved by this urge she began digging her way out. Her legs, never used before, were powerful enough to start loosening the earth that blocked her way to the outside world. With an unerring sense she moved toward the surface, perhaps following some ancestral memory of that world.

The task was arduous but she was young and strong and determined to find her way. It took her several hours and when her head finally emerged at the surface all her senses were bombarded by an accumulation of new sensations: light, colors, smells . . . She tried her wings for the first time and suddenly she found herself airborne. She marveled at her capacity for flying, zigzagging, rising and falling, making sudden turns. The surrounding world, immense and full of sunshine and strange sights, and her just discovered faculties were intoxicating. She kept coming and going taking notice of this unfamiliar land of her birth and its landmarks. She didn’t seem to get tired; there was so much to see. A hungry bird tried to catch her and missed, not because of her skill, but by sheer luck. She would learn to be cautious later on.

That morning she learned that she belonged to a small village of bees that, like her, were emerging from their prolonged sleep and getting drunk on light and air and new experiences. Their wings reflected the rays of the sun. Sometimes, if you walk on a meadow at the right time, you can see them against the sky like constantly moving dots of light.

A dogwood blossom makes a convenient waiting room for a group of boy bees spending the night together in wait for the girls

There were some males among them; some had emerged the previous day and now, past their first exhilaration they were moved by another urge that kept getting stronger by the minute. The scent of the females acted like a magnet and several, full of eagerness, approached and surrounded our little bee. She resisted their advances, not for lack of desire, which she was beginning to discover, but because she wanted only the best suitor. That would be her legacy to her children: the best father that she could find. One male prevailed over the others and joined with her. Now, in delirious ecstasy, both of them, linked by love, rose in the air and flew to a nearby branch where they could enjoy their time together in seclusion.

After their romance and carrying inside herself the sperm of the male, Andrena became all mother. Only one motivation would dictate her actions from now on: to ensure the best for her future children. She was passing on her mother’s heritage even though she would never know neither her mother nor her children.

She started the search for a nest site. What better place than the one her mother had chosen the previous year? It was a patch of soil, warm and with plenty of sunshine, safe from floods and not chocked by vegetation. She landed and started walking in circles looking for the best spot, but somebody else, perhaps her own sister, had already started setting housekeeping there. An angry buzz let her known that she was not welcome nearby. No problem, there were several similar spots not far from this one and she had no trouble finding a good one.

Andrena began digging the hard soil, just like her mother had done a year ago. It was harder than digging up from her cell; the soil was compacted and she had to use all the energy of her young jaws and legs. She kept working full of determination until she realized that she was getting hungry and thirsty.

She flew away from her nest searching for food. A delicious aroma told her that she had found what she was looking for. There were many flowers in the meadow, she landed on an open blossom, found its nectar guided by the scent and drank it thirstily. Andrena went from flower to flower until satiated, then returned to her task.

Back to work she went digging deeper and deeper. Evening came and she needed to rest. What better place than the tunnel she had dug? It was safe there and protected from the night chill. Andrena slept comfortably. The next morning, when her muscles were warm enough, Andrena resumed her work until something told her that she had arrived at the right place; then she started digging a side cavity, this one was a chamber like the one that had sheltered her through her infancy and long sleep.

A mother Andrena gathering food for her babies; her feathery legs make good baskets for the pollen

Now she needed to prepare the chamber for her offspring. That meant many trips to the meadow full of flowers. There she loaded rich pollen in the baskets on her legs and nectar, which she carried in her crop. It took her many trips to have enough for her purpose and another day passed by. She kneaded the pollen and nectar into a thick paste and made it into a tidy ball that nearly filled the whole cell. Satisfied, Andrena laid an egg on top of this loaf and sealed the chamber with some soil

Once again she kept digging another branch of the tunnel, making a new chamber, gathering food, laying a new egg and so on. The days flew by. Sometimes she couldn’t go to work because the weather was foul so she hunkered down, feeling safe in the darkness of her tunnel. One day our little bee escaped a sudden death without knowing it. When she approached a blossom she noticed something different but didn’t give it much importance. Fortunately for her, another bee beat her to this flower. Somewhat annoyed Andrena flew to another one without noticing that a crab spider had caught the other bee in her clutches and paralyzed her with her poison.

All that coming and going wore out her thin wings. They began to fray at the edges and so the day came when, after gathering her usual load of supplies in the meadow, she tried to take off but the extra weight and her aging body and worn out wings prevented her from doing so. She tried again and again but the wind kept slamming her against the ground. So finally, with a sigh and without regrets she surrendered to her fate, knowing that her mission was complete, the new generation was well provided and would repeat the story next spring.

Thus ended one little life made of flowers and sunshine, of dark tunnels and security.

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© Beatriz Moisset. 2010

The pure magnificent green bee

A female Augochlora pura gathering pollen on her leg baskets

Among the many metallic green bees that you see in the summer there is a particularly beautiful one, Augochlora pura. It doesn't have a common name but its scientific one means "pure magnificent green" and it is a very fitting one.

You may have seen this little jewel diligently visiting flowers to gather food for her family. You would be surprised to find out where she takes her load of pollen and nectar. If you could follow her, which isn't easy, you would see her arrive at an old fallen log and disappear inside a crack of the loose bark. That is where she has started building a home for her babies, in the space between the bark and the log. She builds chambers using her own saliva, some wax from her abdominal glands and loose debris, abundant in such places. Later on, she kneads the cargo that she brings from flowers into tiny loaves that look like golden tiles with which she paves the inside walls of the chamber. When there is enough food to feed one baby all the way to adulthood she deposits just one egg and seals the cell; afterward she starts building another one and so on.

A dead log, home to a few metallic green bees

An unhappy mother whose nest has been disturbed when I lifted a chunk of bark. You can see the ripped open cell, where the larva lays surrounded by a nice supply of "bee loaves" made of pollen and nectar

The babies grow on such rich food and emerge in the fall. By then the mother is approaching the end, her wings are torn and frazzled. The bees of the new generation, on the other hand, have a youthful look, with glossy wings and nicely coated by delicate hairs; these are the ones you are likely to see in October and November.

Young females getting ready to hibernate in late fall, November

The young bees mate promptly. This is the end of it for the males who die shortly afterward. But the recently mated females visit some of the abundant fall flowers stocking up on food to see them through the long winter and get busy finding cracks under wood to spend the cold month in safety. By the end of November you are not likely to see any more activity from these handsome bees; but rest assured that they will emerge from their seclusion next spring when the sun warms up the land and when blooms are ready and waiting for them.


 
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© Beatriz Moisset. 2010

POLLINATORS. Robbers and thieves

Some flowers allow only specialized pollinators. They place their nectar out of the reach of most visitors and only those with a long enough tongue can reach it. Such is the case of the bee balm or monarda; a flower visited by hummingbird moths and bumblebees

A hummingbird moth unfurls its long tongue and sticks it inside the equally long throat of a bee balm flower.

The tongue of a bumblebee isn't as long as that of moths or butterflies, but by burying itself into the flower this visitor can reach the store of nectar without difficulty.
These visitors approach the flower the "legitimate" way, meaning that they touch the pollen carrying parts and also the female parts of the flower by entering it this way. When they do so they carry pollen from some flowers to others and accomplish pollination. Everybody benefits; the insects get nourishment and the flowers are pollinated. However this flower's strategy may backfire when clever and lazy flower visitors take a shortcut and steal the nectar. One very common robber is the carpenter bee; with its powerful jaws it can easily slash through a flower's tissues. Here a female carpenter bee is opening the throat of a bee balm flower. When this bee goes directly to the nectar bypassing the sexual parts of the flower it doesn't pick up or carry pollen. As a consequence, it doesn't help the flower at all.

A carpenter bee stealing some nectar

Pollinators: Partners and Robbers
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© Beatriz Moisset. 2010

DECEITFUL FLOWERS. Lady slipper

In most cases the relationship between flowers and their pollinators is a wonderful partnership in which everybody wins; but there are exceptions. In some cases, insects exploit flowers and take their offerings without returning the favor and in other cases it is the flowers that exploit their visitors.
Many orchids use a wide range of deceptions; some, such as the lady slippers, engage in a rather innocuous deceit that only causes the insect a minor inconvenience. This flower has a very peculiar shape, with the lower petal expanded into a bag. The purpose of this bag is to act as a temporary trap.

The drawings show a flower cut through the middle to illustrate what happens.
It is not known exactly what the attractant is, but it is powerful enough that several kinds of bees come to the flower seduced by its appeal.
The bee perches on the edge of the sac and often loses its footing and falls inside; once there it struggles to get out but the inside is slippery and the curled lip of the bag makes it hard to get out. Fortunately for the bee there is a escape route.
Toward the back of the flower there is a ladder made of hairs that leads to a tunnel. There is a sort of skylight at the end of it to guide the disoriented bee, so even though the passage is narrow the bee strives tenaciously headed toward the light. In doing so it rubs its body against the pollen sacs, called pollinia, which get glued to its back.
Once outside the bee flies away; its little brain can remember the unhappy experience long enough to travel some distance from the plant that it has just visited. But most likely, it will repeat this adventure when it finds another lady slipper some time later. At this point it will leave behind the pollinia that it has been carrying inadvertently, performing pollination of the lady slipper and getting no reward for its labor.

Hummingbird Moths. Where do They go in Winter?

Not all moths fly at night; some choose to do it during the day. One of them is the hummingbird moth, so called because it looks and flies and even hums like a diminutive version of a hummingbird when hovering in front of flowers. Just like their feathered namesakes hummingbird moths love long throated flowers, such as bee balm or horse mint. But unlike them, they don’t migrate south when the cold weather arrives. They resort to a different strategy to survive the harsh weather and lack of food.

Like all moths and butterflies they have a complex life cycle with dramatic transformations, called metamorphosis. The distinctive stages are called egg, larva or caterpillar, pupa and adult or imago. The one you are most familiar with is the adult, that colorful flying marvel; the other stages are wingless and prefer to remain out of sight and out of danger. The larva’s job is to eat almost non-stop and to grow; the pupa goes through a resting period and later through a tremendous remodeling job where all the parts are transformed to turn into the active, winged creature which we see during the summer. The flying adult’s whole purpose is to find a mate and to start the next generation; for that they need nourishment, nectar, which they find in flowers.

It is in the resting state of pupa that they choose to spend the winter. After the caterpillar reaches full size feeding on any of its favorite plants, such as hawthorn, black cherry or wild rose, it drops to the ground. There it spins a loose cocoon that lies partially buried under the leaf litter. Leaf litter is very important to this species; it provides some protection against the winter weather and against predators. When birds or squirrels go through leaf litter, scattering it here and there, they may very well be looking for one of these nutritious morsels.

If the pupa survives these attacks, it will complete its metamorphosis and emerge as a winged adult next spring, when nectar-laden flowers are blooming again.

Moths as Pollinators
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© Beatriz Moisset. 2010