16/04/2008 | by Onboard
“What is not good for the swarm is not good for the bee.”
– Marcus Aurelius (Roman Emperor AD 121–180 AD)
Pollination is the process by which plant pollen is transferred from the male reproductive organs to the female reproductive organs to form seeds. In flowering plants, pollen is transferred from the anther to the stigma, often by the wind or by insects.
The sudden mysterious loss of honeybees across the US and around the world is highlighting the critical link that the bees play in human food and crop production. The syndrome is referred to as ‘colony collapse disorder’ (CCD) and growers are becoming worried about the capability of the commercial bee industry (and dwindling wild bee populations) to meet the demand for crop pollination. It has been said every third bite we consume in our diet is dependent on a honeybee to pollinate that food.
NO ISOLATED INCIDENT
Bee losses are ranging from 30 to 60 percent on the US west coast with beekeepers on the East Coast and in Texas reporting losses of more than 70 percent. Three of the UK’s 25 wild bee species are already extinct and European beekeepers have observed similar phenomenon in Belgium, France, the Netherlands, Poland, Greece, Italy, Portugal and Spain; with initial reports coming in from Switzerland and Germany to a lesser degree. Possible cases of CCD have also been reported in Taiwan since April 2007.
The causes of the syndrome are not yet well understood. Theories include environmental change, malnutrition, disease, mites, pesticides and genetically modified (GM) crops with pest control characteristics, such as transgenic maize. Some claim that bee disappearances have not been reported from organic beekeepers, suggesting to some that beekeeping practices can be a primary factor as well.
TOO DRY, TOO STRESSED?
One of the patterns reported by the group at Penn State was that all producers in a preliminary survey noted a period of “extraordinary stress” affecting the colonies in question prior to their die-off, most commonly involving poor nutrition and/or drought. To date, this is the only factor that all of the reported cases of CCD have in common. Accordingly, there is at least some significant possibility that this phenomenon is correlated to nutritional stress, and may not manifest in healthy, well-nourished colonies.
It could also just be that the bees are stressed out. Bees are being raised to survive a shorter off-season which most likely lowers their immunity to viruses. Mites have also damaged bee colonies, and the insecticides used to try to kill mites are harming the ability of queen bees to spawn as many worker bees. In addition, the queens are living half as long as they did just a few years ago. Researchers are also concerned that the willingness of beekeepers to truck their colonies from coast to coast could be adding to bees’ stress, helping to spread viruses and mites, and otherwise accelerating whatever is afflicting them.
Walter Haefeker, a German beekeeping official, has speculated that the fact that genetically modified, insect-resistant plants are now used in 40 percent of cornfields in the United States (as opposed to 0.06 in Germany) could be playing a role. From 2001 to 2004, a research team examined the effects of pollen from a genetically modified maize variant called ‘Bt corn’ on bees. A gene from a soil bacterium had been inserted into the corn that enabled the plant to produce an agent that is toxic to insect pests. The study concluded that there was no evidence of a toxic effect of Bt corn on healthy honeybee populations. However when the bees used in the experiments were infested with a parasite, a significantly stronger decline in the number of bees occurred among the insects that had been fed a highly concentrated Bt poison feed.
Some beekeepers think the culprit may be climate change, in which the Earth as a whole is warming but regional and local temperatures may drop much lower or higher than normal. Erratic weather patterns caused by global warming play havoc with bees’ sensitive cycles. For instance, an unusually dry and warm winter can alter the flowering cycle of many plants, and a sudden blast of hot temperatures as plant buds and pollen grains are beginning to form can create sterile pollen. Flowers are also blooming earlier than in the past, and plants such as red maples and pussy willows – typically the first pollen sources for honeybees – have been blossoming weeks before the bees are ready to fly in the spring.
The term ‘synergy refers to the phenomenon in which two or more discrete influences or agents acting together create an effect greater than that what can be predicted by knowing only the separate effects of the individual agents. Ecology is all about synergy: synergistic patterns, synergistic interactions and synergistic-related consequences.
Honeybees are disappearing, and the salient point is that the bees in the colonies appear to have lost their immunity to viruses, bacteria and disease. The loss of resistance to disease may be caused by parasites, pesticides (both applied and present in GM crops) or climate change. There appears to be no concrete evidence to link the CCD syndrome with any of the aforementioned theories individually. However if you factor them in all together, you get a lethal combination of environmental factors hitting the bee colonies all at the same time.
A quote which has appeared in many of the news features about CCD is: “If the bee disappears from the surface of the Earth, man would have no more than four years to live. No more bees, no more pollination, no more plants, no more animals, no more man.” This quote has often been attributed to Albert Einstein, but the original source for this quote has never been acknowledged, and the earliest known use of the quote is from 1994, 39 years after Einstein’s death.