VanEngelsdorp,
D., Evans, J. D., Saegerman, C., Mullin, C., Haubruge, E., Nguyen, B. K.,
Frazier, M., Frazier, J., Cox-Foster, D., Chen, Y., Underwood, R., Tarpy, D.
R., Pettis, J. S. 2009. Colony Collapse Disorder: A Descriptive Study. Public Library of Science ONE 4(8): 1-17.
Colony
Collapse Disorder (CCD) is a recently discovered phenomenon associated with
three major qualities. Colonies will
have a sharp decline in the numbers of adult honey bee workers. Contrary to expectations, there will be a
lack of dead worker bees in and around the hive. Also, there is a sharp influx of pest
invasion by wax worms as well as kleptoparasitism from healthier hives. CCD is a communicative disease that typically
affects hives during the winter months. In order to gain a more complete
understanding of the disease, extensive studies on colonies and their
susceptibility are necessitated.
VanEngelsdorp et al. performed
studies on CCD colonies in order to characterize the disease, assess risk
factors, and gain further insight into the extent and severity. They monitored commercial hives (healthy,
weak, and CCD hives) in 13 apiaries in Florida and California for sixty days in
January and February 2007. 91 colonies
were observed over the course of the study, and quantitative data were collected
regarding the status of each colony. In
a standard commercial colony, honeycomb is expected to cover 90% or more of the
hive containment. Based on this
statistic, VanEngelsdorp et al. assumed that 60% coverage characterized a week
colony susceptible to CCD infection. The
three identifiable symptoms of CCD discussed previously were used to officially
diagnose a colony. VanEngelsdorp et al.
hypothesized that bee colonies deemed to have ongoing CCD will share common
risk factors such as pathogen exposure or stress factors. Risk factors that were measured include
several macro-parasites, seven viruses, bacteria, and pesticide susceptibility. These factors were quantified over the course
of the study on CCD hives and tested for correlation to CCD infection.
VanEngelsdorp et al. were able to
confirm their hypotheses and ascertain that CCD infection is contagious among
hives based on exposure to certain risk factors. The study was not able to pinpoint an exact
causation for CCD. CCD, however
correlated with several factors: pesticide resistance, European Foul Brood
(EFB), Kashmir Bee Virus (KBV), and multiple other factors. With this information, bee farmers can be more
aware of the risk factors associated with a disease capable of decimating honey
bee populations. Because bees provide
both financial benefits for farmers directly as well as essential pollinator
roles for flowering plant species within their ecosystem, it is essential that
diseases such as CCD are understood and controlled. Farmers may utilize additives to bee hives to
protect their colonies; the threat of CCD could be eradicated or minimally more
properly managed.