Honey Bees Play a Vital Role in the Pollination of Crops - Essay Example

?Introduction Honey bees play a vital role in the pollination of crops as one-third of fruits and vegetables are produced by honey bee pollination. The revenue gained from the use of honey bees as commercial pollinators is estimated to be around $20 billion annually. Beginning from 2006, various beekeepers in most states in the US and in Europe have reported a considerable decline in the population of honey bees, though the general health of the honey bee population has been declining since the 1980s. Considering the severity of the condition this phenomenon is widely being referred to as the colony collapse disorder (CDD), by scientists or as the vanishing bee syndrome (Johnson, 2010; Colony Collapse Disorder, n.d; Colony Collapse Disorder, 2008). The honey bees that leave for the forage largely do not return back to their hives and this is especially witnessed to a large extent with migratory bees which are trucked from one country to another for pollination purposes. Scientists have begun to unravel the causes behind this phenomenon as it is a major source of income for the beekeepers and also the farmers depend on it for crop production (Johnson, 2010). In the earlier times a 10 percent loss in honey bee population in a season was considered to be normal, which then rose to 30 percent due to infection by parasitic mites and beginning from 2006 many commercial beekeepers have reported a loss of 30 to 90 percent average colony loss with the onset of CDD. Even the surviving colonies showed weak viability. Though a majority of the losses have been attributed to known causes about 25% of the loss is estimated to have occurred due to CCD. These losses of colonies occur throughout the year and are not seasonal. The major symptoms of this condition are the rapid loss of adult bee workers without any accumulation of dead bees in the hive which is an indication that these bees are not retuning back to the hive that is highly unusual in case of the bee population. These adult bees leave behind their brood which is generally inactive. In addition, there is also the presence of food stores that includes both honey and bee bread. The queen bee is generally present and actively laying eggs (Johnson, 2010; Colony Collapse Disorder, n.d). In case of actively collapsing bee colonies, only an insufficient workforce of young adult bees will be present and though the queen is present the population does not show an inclination to consume food (Colony Collapse Disorder, n.d). Research carried out to determine the causative factors for this condition has found out that CCD could be a syndrome which is not caused by any one particular factor but a combination of several factors (multifactorial). Some of the major possible factors that threaten the bee population are viruses, parasites and microbes, pesticides, antibiotics, miticides, radiations, genetically modified crops and climatic and other environmental changes (Johnson, 2010; Colony Collapse Disorder, n.d). The USDA’s Agriculture Research Service, the Pennsylvania State University and several other universities are conducting most of the current research to unravel the cause of this phenomenon (Johnson, 2010). A recent study carried out by the Washington State University has shown that CCD could be caused due to a combination of toxic chemicals and pathogens present in honeycombs as the bees present in such combs had reduced longevity (Gutierrez, 2010). Of these, chronic exposures to pesticides, miticides and antibiotics have been shown to have an impact on the immune system of the honey bees and hence on their response to infection. In addition, bees have a reduced number of genes which offer resistance to various diseases and toxins thus making the bee population more vulnerable to such problems (Colony Collapse Disorder, n.d). These toxic chemicals are believed to cause the colony to collapse either by themselves or by combining with each other, which would result in increased toxicity to the hive. In addition scientists are also studying the combinatory effects of viruses that infect the hive and these chemicals and such studies have found that these chemicals could combine with viruses and thereby reduce the immunity of the bees and increase their susceptibility to infection (Honeybees’ Colony Collapse Disorder). Antibiotics are primarily used to control the growth of bacteria in beehives by either killing or inhibiting the growth of bacteria. Miticides are also pesticides which are used to control the mite population and different varieties of miticides like antibiotic miticides and carbamate miticides are available for use. Both antibiotics and miticides are widely being used by beekeepers. The pesticide class includes the commonly used insecticides and, more particularly, in this case the nicotine-based pesticides (Assessment of Current Miticide). Pesticides applied to crops to protect them from insects and other pests are posing a great threat to the honey bees that play a vital role in crop pollination. Various studies conducted have indicated the presence of insecticides and other pesticides in the pollens. Nicotine-based insecticides, like imidacloprid which is the most widely used in this class, affect the central nervous system of the insects by speeding up nerve impulses and block vital neuronal pathways and they affect the honey bees in a similar manner. Studies have established that pollens contain a significant quantity of the insecticide upon absorption form the soil and this polluted pollen has been widely touted to be a major cause of honey bee colony death. Though they are not present at lethal doses, prolonged exposure to these chemicals could result in conditions like CCD. In addition, studies have also shown that these chemicals at the sub lethal levels can cause problems in honey production and foraging of the bees as flight activity and olfactory discrimination was affected and the physiological effects manifested when the dosage level was gradually increased (Johnson, 2010). Thus the possible effects of these chemicals have been well established. But given the exposure dosage it is quite difficult to ascertain for sure that these are the major causative factors for CCD and no detailed study has been conducted on residual pesticide content and their degree of toxicity in CCD affected colonies per se. Hence a more detailed and thorough investigation is warranted to study the extent to which these can cause the disorder (Colony Collapse Disorder, 2008). Miticides are a class of pesticides, which are being widely used to improve the quality of the beehive and the health and longevity of the worker bee. They are however used in sub lethal doses and the effect of two most commonly used miticides, Apistan and CheckMite+, on the bee population is being studied (Assessment of Current Miticide; Colony Collapse Disorder, n.d). The survivability, honey production and foraging rates are being assessed in accordance with the CCD action plan prepared by the national CCD steering committee to test the effects of miticides and their possible role in causing the disorder (Assessment of Current Miticide). In addition to chemicals, infection of the hive by parasitic mites such as Varroa destructor and viruses such as the Israel acute paralysis virus (IAPV), which can be transmitted to the hive by the Varroa mite are also being considered to be key organisms that might cause the disorder (Gutierrez, 2010; Colony Collapse Disorder, n.d; Colony Collapse Disorder, 2008). In the study conducted by the Washington State University has revealed that high concentrations of the pesticides, fluvalinate and coumaphos, which are used to eradicate the varroa mites might also contribute to CCD (Gutierrez, 2010; Colony Collapse Disorder, n.d). Studies have also related infection by the fungus Nosema ceranae, which is an upcoming pathogen for the honey bee population, with CCD. Two honey bees colonies in Spain have been affected by CCD due to this fungus (Colony Collapse Disorder, n.d). This pathogen affects the food processing ability of the bees thus making them susceptible to pathogens and chemicals (Honeybees’ Colony Collapse Disorder; Gutierrez, 2010; Johnson, 2010). Genetically modifies crops have also been scrutinized as a possible cause for this disorder as they release insecticidal toxins from the bacterium Bacillus thuringiencis. Research has revealed that these toxins have a negative effect on the navigation of the bees and CCD has been found to occur in places where Bt crops are grown. Beekeeping practices and changes in the hive due to migration from one place to another is also being studied and so are the effects due to climatic changes and electromagnetic radiations from mobiles, cell towers and wireless networks (Honeybees’ Colony Collapse Disorder). The CCD is also spreading to wild bumble bee populations, which are showing extensive declines, from commercial bees with the infection spread through parasites. In addition, the winters of 2006 to 2008 have also witnessed a large-scale loss of honey bee colonies and many scientists believe that this could be due to the combined effect of both pathogens as well as other environmental stress factors. In order to keep track of the problem, the USDA has established the CCD steering committee which has been trusted with the responsibility to collect data and determine the extent of CCD, analyze the bee samples to determine exposure to pathogens and pesticides, and also chart out and implement measures to improve bee health and their living (Pesticide issue, 2011). In conclusion, while research about the actual cause for the onset of CCD is still in the primitive stages, zeroing on the exact cause should not take long as all the possible causative factors are being analyzed currently. The colony collapse disorder is truly a menacing problem and suitable steps such as research and monitoring, technical assistance to beekeepers, stricter regulations for use of agricultural pesticides and insecticides will have to be implemented before agricultural practices are adversely affected. Reference: 1. Assessment of Current Miticide Use on Honey Bee Longevity and Colony Health. United States Department of Agriculture. Retrieved April 11, 2011, from < http://www.reeis.usda.gov/web/crisprojectpages/213332.html> 2. Colony Collapse Disorder. Our Food Database of Food and Related Sciences. Retrieved April 11, 2011, from http://www.ourfood.com/Colony_Collapse_Disorder.html 3. Colony Collapse Disorder: A Complex Buzz. (2008). United States Department of Agriculture. Retrieved April 11, 2011, from http://www.ars.usda.gov/is/AR/archive/may08/colony0508.htm 4. Gutierrez, D. (2010). Honey Bee Colony Collapse Disorder Finally Explained: Too Many Chemicals. Natural News. Retrieved April 11, 2011, from http://www.naturalnews.com/028429_colony_collapse_disorder_chemicals.html 5. Honeybees’ Colony Collapse Disorder: Where have all the workers gone? Retrieved April 11, 2011, from 6. Johnson, R. (2010). Honey Bee Colony Collapse Disorder. CRS report for Congress. Retrieved April 11, 2011, from http://www.fas.org/sgp/crs/misc/RL33938.pdf 7. Pesticide issue in the works: Honeybee colony collapse disorder. (2011). U.S. Environmental Protection Agency. Retrieved April 11, 2011, from http://www.epa.gov/pesticides/about/intheworks/honeybee.htm Read More