Monday, April 9, 2012

Colony Collapse Disorder

I am taking a break from promoting green products and companies to talk to you all about something really important, Colony Collapse Disorder. 
Apis mellifera or the European honeybee is vital to Humans. Not only are honeybees the only producer of honey a food that has been called the elixir of life and the nectar of God, but honeybees are responsible for a good amount of the world's pollination of plants and flowers, and almost all of the world's pollination of commercial crops. Without them we as a species, would see a dramatic loss of most of our world's food supplies and perhaps even be faced with famine or the extinction of our species as a whole. Honeybees are vital to our survival. The Honeybee has evolved to be the perfect pollinator. It has hairs on its legs that collects pollen as it collects nectar to eat. Flying from flower to flower pollen can mix which cross pollinates the blossoms. Nectar is a clear sugary liquid that is taken from the flowers and stored by the honey bee in a second stomach before they regurgitate the then honey into the honeycomb cells where it is used for food for the larvae. The Honeybee is colonial. They form a hive where one queen lays the eggs, while worker sister bees build the hive, care for the young and find nectar and honey. In a honeybee hive communication is key in the survival of the community and honeybees have evolved a sophisticated technique of dancing to communicate commands to their sisters. The male honeybees are drones which live in hopes of mating with the queen.
When Europeans came to America for the first time they brought with them the European Honeybee. It was a source of life for the early settlers, giving them both honey and pollinating their crops. There were of course other species of bees living in America already which did not produce honey but did help pollinate crops and still do today. Since then the Honeybee has been a major part of agriculture in America. “Large acreages of pollinator-dependent crops, such as apples, almonds, blueberries, and cranberries, require managed pollinators to ensure production. The ability to easily move and manage honey bees, Apis mellifera, makes them ideal for this purpose. In all, it has been estimated that directly, and indirectly, one-third of the food we eat comes from honey bee pollination.” (Vanenglesdorp, 2010). However as commercial agriculture grew and became more mechanized and chemical so too did apiculture or beekeeping. Hives have been exposed to chemical fertilizers, pesticides, genetically altered flowers and crops, and worst of all have been fed syrups and fillers instead of being allowed to gather nectar naturally. All these things have helped bring about one of the largest crises that our world has faced yet, Colony Collapse Disorder in honeybees.
Colony Collapse Disorder can be defined by a few different things, but commonly is known to show a few common symptoms which can be used as a gauge for finding CCD. The symptoms associated with CCD are “1. The complete absence of adult bees in colonies with few or no dead bees in/ around colonies; 2. The presence of capped brood; and 3. the presence of food stores that are not robbed by other bees or typical colony pests.” (Ellis et al. 2010). There are also certain symptoms associated with a collapsing colony and can be used to diagnose weakening colonies. “1. An insufficient number of bees to maintain the amount of brood in the colony; 2. The workforce is composed largely of younger adult bees; 3. The queen is present; and 4. The cluster of bees is reluctant to consume food provided to them by the beekeeper. (Ellis et al. 2010). In lamens terms Colony collapse Disorder is the disappearance of large amounts of adult bees from an individual hive or colony with no dead bees found or probable cause.
A survey was done in 2010 showing declining bee populations over the last 60 years. From 1940-2008 data was taken from apiaries with more than 5 colonies. The results show clearly a he drop off in population sizes over the last 10-15 years. In 1940 there were approximately 6 million bee commercial honeybee colonies. By 2008 there were less than 2.5 million commercial bee colonies.
According to Ellis et al. 2010, this data was taken from the National Agricultural Statistics Service in 2009. In the documentary “Vanishing of the Bees”, they show that every year beekeepers are reporting 1/3 losses of their adult bees due to CCD. If this were to happen to any other food source it would become an instant national disaster but since they are insects the beekeepers do something called splitting the hive, where they cut the hive numbers in half and add a new queen to the one half in a new hive box and begin accumulating new bees. Bees like all insects reproduce very quickly and so in a short time they can recoup their losses, but this is a short term solution. (Vanishing of the Bees, 2009)
If Colony Collapse Disorder is causing such a vast drop off in honeybee numbers around the world and specifically in the US, what can be causing this? There are many hypotheses. One of the most prevalent is that the exposure to pesticides is the cause (Vanengelsdorp, 2010) (Frazier et al., 2008), while others say that exposure to mites, fungi and disease is the cause (Higes et al., 2009) (Maori et al., 2009) (Bromenshenk et al. 2010). Another theory is that the use of syrups and fillers fed to bees in order to fast track production and artificial insemination of queens is the main cause. (Vanishing of the Bees, 2009). On the whole though no one cause has been found or agreed upon, though all agree this problem is threatening agriculture as we know it today and the future of bees in general.
The first possible cause, pesticides, is thought to be more of a contributing factor than the main cause. In a study in 2008, What have pesticides got to do with it? (Frazier et al.) discussed how the use of most of the nation’s hives of honeybees are used for rotating crop pollination in large commercial farms. They are exposed to large amounts of pesticides as a result. There is also a large amount of miticides used in the hives directly to help combat the mites that have been now linked as another possible cause of CCD. The real concern with the pesticides being a contributing factor in CCD is not the lethal doses, we now are seeing that non lethal doses are lowering the bees immune systems and allowing for other diseases to attack the hive and take it down. “We are becoming increasingly concerned that pesticides may affect bees at sublethal levels, not killing them outright, but rather impairing their behaviors or their ability to fight off infections. For example, pesticides at sub lethal levels have been shown to impair the learning abilities of honey bees or to suppress their immune systems. For these reasons we believe that pesticide exposure may be one of the factors contributing to pollinator decline and CCD.” (Frazier, 2008).
The second possible cause is mites, viruses, and fungi. In a study by Higes et al. 2009, it was proposed that Nosema ceranae a fungi Microsporidia was a main cause of CCD. “There was evidence of epithelial cell degeneration and extensive lysis. As described previously, heavily infected cells may be either dead or dying, which will eventually lead to the early death of the infected workerbees due to starvation.” (Higes et al. 2009) This fungi heavily impairs the hive as a whole and the infected bees found to be infected did not have other diseases, which could mean that this is a main cause of CCD. Another study by Bromenshank et al., 2009, also confirmed this. This study however also looked at another disease an iridovirus. It did not show that iridovirus on it's own could cause CCD which further shows that microsporidia is a more likely cause. Iridovirus though is most likely a contributing factor. In a study, Maori et al. 2009, they discuss how the iridovirus is able to be silenced with the ingestion of dsRNA. This was tested on nemotodes and proved to be successful. “RNA silencing down regulates gene expression by degrading RNAs in a sequence-specific manner, arresting the translation of a designated mRNA, or engendering transcriptional gene silencing involving DNA methylation and chromatin remodeling.” (Maori et al. 2009)
The last possible cause was discussed in a 2009 documentary, The Vanishing of the Bees. They showed how many hives are now being fed syrups and fillers in order to produce more and more honey with less and less bees. This is causing the entire health of the hive to decline. It is compared to feeding your children nothing but junk food and then their children and then their children. Eventually you wold have harmed your entire genetic fitness of the family and they would be riddled with disease. The believe this is what is happening with the bees who have CCD. They also discuss CCD being caused by genetic engineering and artificial insemination of queens for certain traits. This is further harming the hives as a whole. Their overall fitness has decreased considerably.
The cause that seems the most plausible is the combination of all of these. One common symptom of Colony Collapse Disorder in honeybees when scientists study them is a large amount of diseases. It seems that their immune systems are compromised drastically. “The condition of the quality of the brood pattern was also noted with areas of capped brood containing less than 80% viable brood.” (Vanenelsdorp et al. 2010) I hypothesize that the pesticides, miticides and genetic engineering and poor diet are all lowering the honeybees immune system to the point where the microsporidians and iridoviruses can take over, killing off whole hives in a matter of days. It would be as if humans all had AIDS or another immune suppressing disease, and as a species this had become normal. Well what would happen if the flu ran through a society riddled with AIDS? We would die off in force. It would very quickly decrease our population within a few weeks even, to numbers so low that we probably could not recover. This is what CCD is doing to bees. The problem is when people began to mess with bees in a large way, exposure to pesticides, genetic engineering.. we reduced their fitness. We tried to domesticate an animal that does not do well being domesticated.
So what can be done about CCD? Many of the sources I read all had the same thing to say, but the documentary, Vanishing of the Bees, 2009, went into the most depth. They proposed that instead of large beekeepers who keep thousands of hives, that thousands of people need to have 1 hive each. They are calling for anyone who would like to help to raise bees in their yard or small farm, organically, with no filler food, no interference, and no exposure to pesticides. It is theorized that if even a few thousand small organic farmers each kept one small hive we could start to turn CCD around in a few years. Colony Collapse Disorder is a true threat to not just bees but to humans everywhere. If the answer is such a simple one, it begs the question, what are we waiting for?

Works Cited

Maori, E., Paldi, N., Shafir, S., Kaley, H., Tsur, E. 2009. IAPV, a bee-affecting virus associated with Colony Collapse Disorder can be silenced by dsRNA ingestion. Insect Molecular Biology. 18 (1), 55–60
Blackwell Publishing Ltd
Neumann, P., Carreck, N. L. 2010. Honey bee colony losses. Journal of Apicultural Research 49(1): 1-6

Bromenshenk, J. J., Henderson, C. B., Wick, C. H., Stanford, M. F., Zulich, A. W., Jabbour, R. E., Deshpande, S. V., McCubbin, P. E., Seccomb, R. A., Welch, P. M., Williams, T., Firth, D.R., Skowronski, E., Lehmann, M.M., Bilimoria, S. L., Gress, T., Cramer, R. A.

Bromenshenk JJ, Henderson CB, Wick CH, Stanford MF, Zulich AW, et al. (2010) Iridovirus and Microsporidian Linked to Honey Bee Colony Decline. PLoS
ONE 5(10): e13181.

vanEngelsdorp D, Evans JD, Saegerman C, Mullin C, Haubruge E, et al. (2009) Colony Collapse Disorder: A Descriptive Study. PLoS ONE 4(8): e6481.

vanEngelsdorp D, Hayes J, Underwood RM, Pettis J (2008) A Survey of Honey Bee Colony Losses in the U.S., Fall 2007 to Spring 2008. PLoS ONE 3(12):e4071.

Higes, M., Martín-Hernández, R., Garrido-Bailón, E., González-Porto, A. M., Nozal, M., Bernal, J. 2009. Honeybee colony collapse due to Nosema ceranae in professional apiaries. Environmental Microbiology Reports.

Frazier, M. T., C. Mullin, J. Frazier. 2008. What Have Pesticides Got to do with it? Amer. Bee J. 148:521-523.

Frazier, M. T., C. Mullin, J. Frazier. 2007. Preliminary Report to Sponsor on Pesticide Residues in Pollen, Spring 2007. The National Honey Board.

Langworthy, G. 2009. Vanishing of the bees. Documentary.

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