Colony Collapse Disorder

Each time large-scale colony losses occur, it prompts animated debates between scientists generally without a clear-cut resolution (Rennie et al., 1921; Bailey, 1964; Oertel, 1965; Foote, 1966; Kauffeld, 1973; Olley, 1976; Thurber, 1976; Wilson and Menapace, 1979; Shimanuki et al., 1994; Tew, 2002; Svensson, 2003; Anderson, 2004). In this recent case researchers are focusing on a wide range of pathogens and external causes (parasites, viruses, pollen, nectar, pesticides and stress), but at the moment the pathogen responsible for the syndrome has not yet been found (Cox-Foster et al., 2007; Stokstad, 2007a,b; Oldroyd, 2007; Anderson and East, 2008; Cox-Foster et al., 2008).

Recently, a virus called Israeli Acute Paralysis Virus (IAPV) has been considered as a marker and has been suspected (but not confirmed) to be the pathogen responsible for CCD, or at least a co-factor (Cox-Foster et al., 2007; Palacios et al., 2008). The problem of confirming this virus as a marker for CCD is its close relationship with other two viruses called Kashmir Bee Virus (KBV) and Acute Bee Paralysis Virus (ABPV) (de Miranda et al., 2010a ); this similarity between these three viruses often leads to misidentification (Palacios et al., 2008).

At the moment further work is required to elucidate the precise role(s) that these viruses play in this syndrome , and if they act alone in the causation of the disease or if they need external factors that can boost their virulence (Cox-Foster et al., 2007, 2008; Anderson and East, 2008; van Engelsdorp et al., 2008).

You can find more information about CCD following the Videos page or going to the USDA ARS dedicated webpage.

Considerations about CCD and hive loss

CCD is characterized by a sudden loss of hives (up to 90%) in apiaries without a clear precedent history of disease (van Engelsdorp et al., 2007, 2008; Cox-Foster et al., 2007). CCD syndrome can be differentiated from colony losses caused by other means by a rapid reduction in the adult bee population with no sign of dead bees inside the hives or in the region of the apiary (van Engelsdorp et al., 2007, 2008; Cox-Foster et al., 2007). CCD colonies often have plenty of stores (honey and pollen) and a large area of untended brood. Often the queen remains with a small group of young attending workers (van Engelsdorp et al., 2007, 2008; Cox-Foster et al., 2007). What is really strange is that the hive products are not stolen by other bees and even the wax is not spoiled by the wax moth as usually happens when an abandoned hive is left in the field. Basically both honey bees and moth seems to refuse the products of the abandoned hive.

Apart from CCD, large-scale bee losses with apparently cryptic causes have been shown to occur throughout history, and the phenomenon is quite constant across the years as shown in Table 1.1.

Tab 1.1: Summary of the historical reported colony loss. Shown are the year when the colony loss happened, the location, and the author that described it. (de Miranda et al., 2010a )