Colony Collapse Disorder

Colony collapse disorder or CCD was one of the biggest news items in 2007.

Disappearing winter cluster

By Feb 2007 an alarming number of honeybee colonies deaths were being reported across the United States. Many large commercial beekeeping businesses were recording colony losses between 50 and 90% with many surviving colonies too weak to be used for either pollination or honey production. Similar inexplicable colony collapses were also being reported in parts of Europe worrying both beekeepers and bee scientists everywhere. The symptoms might vary but the result was similar; the undiagnosed deaths of a large number of honeybee colonies. (Max Watkins April 2007)

Pollination by bees is valuable to the economy.

The current CCD phenomenon dangerously threatens the beekeeping industry and its pollination services in the US. More than 90 crops in North America depend on hneybee pollination estimated to be worth over $14 billion annually. Almond production in California alone is worth $2 billion and is almost entirely dependent on honeybee production and around three quarters of a million colonies will be taken there for this purpose (Claire Waring April 2007 and Dennis vanEngelsdorp Sept 2007)

How is CCD recognised?

Colony Collapse disorder is characterised by sudden colony death with a lack of any adult bees either within or in front of the colony. Robbing of the dead colony is delayed and there is slower than normal invasion by common pests such as wax moth or small hive beetle. These symptoms are similar to those of Varroa collapse. Varroa mites may be interacting with one or more of the 14 known bee viruses where transmission is facilitated by high varroa populations (Stephen J Martin June 2007) while separating out normal winter losses from unusual or inexplicable losses is a challenge to scientists.

What causes CCD?

At first it was not clear what was causing the colony deaths and, although many of the more fanciful causes were ruled out (rapture – bees being taken into heaven by God!), the following areas are being actively investigated by US scientists: chemical contamination or residues, known and unknown pathogens, parasite load, nutritional fitness of adult bees, stress levels of adult bees or lack of genetic diversity. (Maryann Frazier, Dennis vanEngelsdorp, Dewey Caron April 2007 and Waring July 2007). Research showed varroa was not the cause, nor was acarine nor even the virulent strain of Nosema (Nosema ceranae) that had been newly described in Spain (Max Watkins April 2007 and Araceli Costa June 2007) and later found to be widespread in the US (Dennis vanEngelsdorp Sept 2007). Later in 2007, Israeli Acute Paralysis virus (IAPV) emerged as a strong suspect in the hunt for the cause of CCD. This virus appears to be ‘strongly associated’ with CCD turning up in over 80% of samples from hives affected by CCD. Whether IAPV is a causal agent of CCD or just an effective marker is still an open question. Most experts think a single cause is unlikely currently considering a combination of factors a much more credible scenario (Waring Oct 2007 and Jan 2008).

Item summarised from the ongoing reports in Beecraft throughout 2007. Click here for the latest update

The latest research details can be found on the Mid Atlantic Apicultural and Extension Consortium (MAAREC) website www.maarec.cas.psu.edu/Colony CollapseDisorder.html

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