Causes to Bee Deaths and Their Interactions
Many factors can cause bee deaths. The most commonly implicated are pathogens viruses and cell phones. Here are some of the possible causes and their interactions. Acute bee paralysis virus deformed wing virus and Israeli acute paralysis virus are just a few. As a result researchers must explore the interactions between all these agents to better understand the cause of the disease. Pathogens implicated in CCD include Ascosphaera apis chronic bee paralysis virus deformed wing virus Kashmir bee virus and American foulbrood.
Viruses
Researchers have found that viruses cause bee deaths. DWV-B and C were found to be the most common causes of honey bee mortality. These viruses persist in the hive without visible symptoms destroying the bees' health and fitness even when conditions are favorable. The researchers hope to find ways to develop bees resistant to these viruses and will continue their research to find a cure for bee disease.
There are many different kinds of bee viruses including the deformed wing virus the most common. The deformed wing virus is an RNA virus that creates several genetically heterogeneous forms including several master variants. Type A has been attributed to the decline of honey bee colonies worldwide while type B has not yet been linked to bee deaths. Viruses can also cause bee deaths because they affect the mite Varroa.
The prevalence of bee deaths varies between different habitats. In national parks and agroecosystems all nine viruses were found. National parks had the lowest mortality rates and towns had the highest prevalence of viral infection. However viruses can easily spread from one colony to another which could affect the ecosystem's stability and species composition. If this is the case we may have to consider preventing a virus-infested bee population from being introduced to the local environment.
The European foulbrood virus referred to as M. plutonius is caused by an entomopathogenic fungus. It causes the mummification of bee larvae within the colony weakening the colony and allowing other pathogens to take hold. The disease is a major economic threat in the global beekeeping industry. If left untreated the symptoms could be fatal to a bee colony.
CBPV (chronic bee paralysis virus) is a well-defined viral disease in honey bees. Bees that develop the disease typically lose their entire colony. There is anecdotal evidence that the virus has recently increased in incidence. Government records of honey bee health inspections indicate that the disease has increased exponentially between 2007 and 2017. There may be an ongoing global outbreak of the virus.
Pathogens
Fungi are common insect pathogens that have a wide range of effects on insect populations. Some species have become so important for agriculture that they are considered agricultural biopesticides. They thrive in warm moist environments and that includes the bee nest. Although only a few species have been studied for their effects on bees there are likely many more lurking in the background. If you think your bees are safe take some basic precautions.
Researchers from the Edgewood Chemical Biological Center in Oregon found that two viruses were associated with elevated bee mortality. The virus pCCA induced a strong immune response in the bees which in turn led to the bees' deaths. They also found a link between two different viral RNAs which caused bee deaths. The scientists presented their findings to a working group of the United States Department of Agriculture.
Infected bees exposed to pesticides have a lower survival rate. Their gut microbiome is also less likely to develop resistance to the pathogen which increases the likelihood of a colony collapse. Infected bees may also develop resistance to pesticides which may contaminate honey. A compromised immune response may be a contributing factor to CCD. However the study did not provide conclusive evidence to link the two diseases.
A case study of a single colony in Switzerland in October 2009 has raised concerns about the pathogens causing colony collapse disorder (CCD). Although the Swiss Bee Research Centre matched the criteria of US hive surveys laboratory tests for bacterial fungal and viral infections found that the disease was not a factor in this particular incident. A new species of nosema has been detected in bee samples dating back to 1995. Nosema apis is a microsporidian that lives in honey bees' digestive tracts. It can cause bee colonies to leave their colony.
Fungi infect stressed hives and can infect the larvae and pupae. Although these are not directly implicated in the cause of CCD there is no simple explanation for the association between pesticides and pathogens. It's likely that the presence of pesticides in hives weakens the bees' immune systems and digestive tracts making them susceptible to infection by pathogens. Ultimately research is needed to find out the connection between pesticides and CCD and how they impact the bees.
Plants
The mysterious mass die-off of honey bees has left farmers scrambling to figure out the cause. In the US alone they pollinate more than $30 billion in crops. In the Netherlands a particularly harsh winter could leave fields fallow. But new research pinpoints several likely causes. It will be much harder to avert beemageddon if researchers can't pinpoint the cause. This article will give you a better understanding of what is happening to your bees.
While individual causes may weaken bee populations multiple factors together can be disastrous. Despite the widespread impact of several factors scientists are still trying to figure out which factors are causing bee deaths. To begin let's look at some of the main causes of bee deaths. Here are a few of them:
Silver linden - While silver linden has been associated with bee deaths it is not the only plant that causes bee mortality. Some species of linden produce toxic nectar. The common linden is a hybrid of Tilia cordata and Tilia dasystyla. It's not known whether any other linden species is responsible for bee deaths. Some researchers say it's a combination of these two types of plants.
Pesticides - The effects of pesticides on bees are unknown and the causes of bee mortality are still under investigation. Many factors contribute to the increased mortality of worker bees including the use of pesticides. These extra losses are damaging to the bee population and the dynamics of the community. However a few dead bees is not a cause for alarm. For example a weakened population of bees could result in reduced pollen and nectar levels.
The loss of bee colonies varies by region. In the EU losses have reached historic highs. While there are no reports in many regions of the world in the USA more than half of the colonies have disappeared. In the same time frame some beekeepers in the US had to rebuild all of their colonies. The phenomenon was deemed a 'colony collapse disorder' by scientists. And while the death rate is a serious concern it isn't as disastrous as many fear.
Cell phones
Bees react to cellular signals differently than people. They tend to lose track of their surroundings. A study published in the Journal Apidologie found that the noises from cell phones could be a signal for a swarming bee colony. Bees in the experiment responded by making high-pitched sounds. However there was no effect on the number of bees killed. Bee deaths are a serious issue and cell phone use must be banned in beehives.
Earlier studies have suggested that cell phone use may be a contributing factor in bee deaths. Bee populations declined by up to 30 percent in the United States and 17 percent in the UK last year. Although the causes of colony collapse disorder are numerous - climate change pesticides and viruses - researchers from India believed that cell phone radiation could be a major contributor. In one study researchers placed fake cell phones around another hive while a third hive had no mobile phone use.
To determine if cell phone use is a factor in bee deaths researchers from the Panjab University in India fitted mobile phones in beehives. They then observed that the bees produced less honey and their number dropped drastically after three months. The number of queen bees also decreased and the size of the hive was reduced. According to the researchers it seems that the chattering radiation is interfering with the bees' navigation. Further research will need to be conducted but for now the researchers are calling for a temporary moratorium on the deployment of 5G in beehives.
Scientists at the Swiss Federal Institute of Technology in Lausanne have concluded that the frequency of cell phone signals sent by cell phones causes bees to respond differently. Bees emit high-pitched squeaks as a result of the cell phone signals. They then decide whether to swarm or flee. The resulting buzzing noise caused the bees to panic and swarm which can be fatal to a bee hive.