Category Archives: Hoverfly

More pollinator diversity…

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Vanishing bees?

Hello – here is a response to the recent question about the disappearance of honeybees in Europe and North America. This phenomenon has been called Colony Collapse Disorder, also known as CCD, is a mysterious and widespread phenomenon of the sudden disappearance of entire colonies of honeybees from their hives and the environment.

 

CAUSES

No single cause of CCD that has been identified by scientists, and speculation as to the ultimate reason for this dramatic loss of honeybees is rife. Many scientists seem to be moving towards a consensus that this may not be the result of a single factor, but more due to the cumulative effects of a number of things, including:

 

Nosema – this is a vicious little parasite that infects the honeybee gut. It is related to fungi-like organisms and similarly to the human gut pathogen Giardia, and has an equally debilitating effect on honeybees. Infection leaves honeybee colonies weakened and vulnerable to other parasites. Scientists have tracked its spread through honeybee colonies in Asia, Europe and North America over the last few years.

 

Pesticides – a number of pesticides are especially toxic to bees, even in very low doses. They are designed after all to kill insects, and honeybees are insects just like the pests the chemicals target. Some pesticides impair the honeybees’ learning ability and others affect their orientation and navigation leading to a breakdown of the colony over time through repeated exposure.

 

Mites and viruses – The mite, Varroa destructor, and the many associated viruses it transmits to honeybee colonies are one likely cause of the demise. Some farmers have resorted to treating mite infestations with chemicals that have also accumulated to levels that affect the honeybees.

 

Electromagnetic radiation – there is little evidence for this apart from one study that embedded receivers inside hives. Emanating from cellular-phone and other telecommunication devices these waves are thought to disorient bees.

 

Genetically-modified crops – again here there are no direct studies. A number of GMO crops produce toxins engineered from bacteria and if these are present in the pollen it could affect foraging honeybees.

 

Bad beekeeping – one characteristic of the modern honeybee industry in the developed world is the trucking around of thousands upon thousand of colonies. These are often mixed and housed in close proximity allowing for the transmission of diseases.

 

Climate change – again here there’s no direct evidence. Colonies that were overwintering now run out of food stores as erratic weather patterns play havoc with flowering cycles and nectar flows.

 

EFFECTS

The full effects of the disappearance of honeybees are yet to come. Bees and other pollinating insects are responsible for one in three bites of food. Some of the effects witnessed so far include:

 

Loss of almond pollination ‘services’ in the Western United States. Some 90 % of the world’s almonds are grown in California. The almond trees flower early in spring and require pollination by honeybees trucked in from far and wide. Due to the lack of honeybees for commercial pollination of the crops, the production of almonds has dropped significantly.

 

The 100 million sterling-pound plus contribution made by honeybees to the UK’s economy was dented severely this past Christmas season as there was virtually no British honey on supermarket shelves. The UK has seen some two-thirds of its honeybee colonies vanish and the remaining ones are stressed and weak. Frighteningly there’s evidence emerging now that bumblebees too are starting to go the same way as honeybees!

 

Honeybees have featured recently in the politics of economic recovery as both the Europeans and the Americans have included honeybees and pollination services as part of their studies and strategies towards overcoming the current financial global crisis. While this has attracted ridicule of the Obama administration by political opportunists, who are laughing at this as ‘frivolous’, many people, including some of the world’s leading scientists are begging politicians and decision-makers to take an interest in solving this problem.

 

Is there hope?

Yes – there is evidence that with help some honeybee colonies can recover. Also, a little known fact is that there are thousands upon thousands of other pollinators available and working hard on our farms. We need to understand and protect these overlooked creatures as we work towards a solution for the current honeybee crisis.

Early Riser

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Dawn on the plains here is crisp and bright. A tangled sky with the promise of rain greets each day. Sunlight streams softly through the mosaic of clouds above and fresh leaves below. Everywhere life returns and sprouts with abandon. Finally, after months of hot, dry, dusty days, the time to flower, fruit, lay eggs, pollinate, claim territories – basically reproduce in every way imaginable, has come.

In the very first rays of light, just before sunrise, when you can still see your breath, and the torrent of birdsong flows steadily all around, another, fainter, more frantic sound can be heard. A steady, humming, soft, consistent, punctuated now and then by a staccato of pauses. For several days I’ve puzzled to what it is. It is still too cold for even the most diligent of bees to be about. They are all snuggled up in their hive, waiting for the sun to climb just a little bit higher in the sky. So it’s not the bees.

Could it be the termites? They are busy building empires up the sides of the house rapidly conquering the wooden beams and struts. I listen more closely, – hmmm, no, it’s not the termites. This humming sound has a steady buzzing quality to it. The termites, rattling their heads against their earthen walls, sound far more erratic. So the termites can’t be blamed, despite their many other sins.

Looking out over the tangle of leaf and creeper all is still and calm.
Just this loud buzzing sound. Well, it must be coming from the air! A cloud sifts the sunshine and a sunspot shifts right in front of me.
Before I can move my hand into it, to see if I can feel any warmth in the cold air, a flash of light zips down and claims it.

The flash of light zips back and forth humming loudly all the while.
Whoever this is – they are responsible for the pre-dawn buzzing sound.
The cloud passes and the sunspot settles. And so does its claimant.
Now I can see that the buzzer is an insect. A hoverfly.
He has claimed the sunspot as his own to display in. He holds his place perfectly, wings a whirr of aerodynamic perfection. He is so bold and confident that even as I fiddle clumsily with the camera he barely budges. Then, with a stroke of luck (at 1/4000th of a second!), his dance is captured, and my insatiable curiosity briefly sated.

PS – Many, many thanks to all of you who read this blog and send me comments and questions. I really love hearing from you, and I am so glad that even the smallest creatures are of interest to so many. I apologize for not posting more often – but I am back home in Kenya now for a few months and I will be posting lots more (when I have internet access!).

Asante sana!