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--Apple-Mail-183--60780727 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=WINDOWS-1252; delsp=yes; format=flowed Hi folks, There has been some recent discussion on naturens of Colony Collapse =20 Disorder (CCD), the recent phenomenon that has been noted in relation =20= to bee colonies in a number of areas. This following article =20 originally appeared in Hivelights [20(2): 18-20] and then was =20 reprinted in the most recent Bulletin of the Entomological Society of =20= Canada [Volume 39(2) June 2007]. I thought it might be of interest to =20= naturens subscribers Cheers, Chris Colony Collapse Disorder (CCD) in Canada: Do we have a problem? Peter G. Kevan, Ernesto Guzman, Alison Skinner, and Dennis van =20 Englesdorp Colony Collapse Disorder (also known by several other names) has =20 become a plague in throughout the United States. Major losses in =20 colonies have been reported from all states that have reported =20 (http://maarec.cas.psu.edu) as of 26 February 2007. In Canada, where =20 winter losses are com monly problematic, no instances of CCD have =20 been confirmed, at least so far. But, very recent reports are of =20 suspicious losses having been experienced in Ontario and =20 Saskatchewan. Should Canadian beekeepers be concerned? Does Canadian =20 beekeeping provide insights into CCD? Let=92s first look at the information that the CCD Working Group in the =20= USA has provided (http://maarec.cas.psu.edu). The symptoms of a CCD collapsed colony are no adult bees and no =20 corpses, presence of capped brood, presence of both honey and pollen =20 (bee-bread) stores. A collapsing colony shows too small a workforce =20 for colony maintenance and that workforce is made up of young bees, =20 and the bee cluster seems reluctant to feed on either stored honey or =20= pollen. One of the most peculiar of symptoms is the lack of robbing =20 behaviour of surviving colonies of colonies that have died out. What =20 is going on? Strange symptoms indeed! The CCD Working Group concludes that =93stress=94 is a major contributor = =20 to the condition, and they itemize a number of stresses that are =20 likely involved. In particular, they mention that migratory =20 beekeeping practices are stressful to the bees. The reasons suggested =20= are con=ADfinement and temperature fluctuations during transport. =20 Certainly, added to those reasons are the mechanical vibrations and =20 shocks that colonies on trucks experience, which, when protracted =20 over several days=92 duration would be upsetting to the bees. =20 Confinement itself would cause the air within the hives to become =20 stale, with higher than usual levels of Carbon dioxide (CO2) and =20 moisture. Even moving colonies short distances for pollination or =20 honey production is well known to cause the bees to become upset, so =20 moves taking days and over thousands of kilometres would be expected =20 to be stressful on the bees, as well as on the beekeepers. Rapid movement of colonies of bees across the USA may cause =93jet-=20 lag=94. Yes, bees do sleep and do have regular daily rhythms of ac=AD=20 tivity (just as do people) (Kaiser 1988; Sauer et al. 2003, 2004; =20 Zhang et al. 2006), so one can suggest that a colony of bees being =20 whipped across two or three time zones in a quick move would be =20 subject to some stress. Migratory beekeeping involves the packing of =20 large numbers of colonies onto the backs of trucks. There, the =20 colonies are un-naturally close together. The CCD Working Group ac=AD=20 knowledges that when the bees cluster on the outsides of hives packed =20= as truckloads, mingling of bees between the hives would occur. The =20 bees=92 defecation on the outside of the hives would increase rates of =20= transmission of pathogens. That transport in and of itself causes colony death and the CCD =20 Working Group reports that 10% to 30% losses are =93not uncommon=94 as a = =20 result of moving colonies for pollination. With such losses, =20 migratory beekeepers make splits to compensate for the losses. The =20 Working Group notes that the reuse of equipment from hives that have =20 died out is part of the transfer of diseases and chemical =20 contaminants and may contribute to the problem. They also point out =20 that making splits changes the age structure of the colonies being =20 split, and results in an un-natural age structure of bees in the =20 split itself. Thus, the ratio of young, nurse workers to older =20 foragers becomes imbalanced, further stressing the colonies. Although migratory beekeepers seem to have suffered badly, reports of =20= CCD are not confined to their operations. Other stresses noted by the =20= CCD Working Group are overcrowded apiaries, nutritional stress, =20 drought and contaminated water, use of antibiotics and chemical =20 pesticides (within and outside the hive) and, of course, mite =20 parasitosis. Overcrowded apiaries are commonly part of migratory beekeeping, =20 especially for pol lination services. The =93staging apiaries=94 where =20= hundreds of hives are placed cheek-by-jowl are not healthy for the =20 bees. Often there is not enough food within the flight ranges of the =20 foragers, robbing is commonplace (and would lead to disease =20 transmission), and hives weaken despite the efforts of the beekeepers =20= to provide food (pollen or pollen substitute and syrup). Nutritional stress is not really addressed by the Working Group, but =20 several points are worth mentioning. Honeybee colonies used for =20 pollination services on large monocultures, such as almonds, =20 blueberries, alfalfa are placed in environments where little or no =20 food choice is available to them. It is known that a diverse diet of =20 a mixture of pollens from different plant sources is beneficial to =20 bees, and the same would be true for nectar (Schmidt et al. 1987, =20 1995). Thus, nutritional imbalance could ex plain, in part, some of =20 the observed symptoms. Moreover, the situation for almonds is com =20 plicated by the potential toxicity of pollen and nectar from almond =20 flowers (Kevan and Ebert 2005), especially perhaps in large quantity =20 and for prolonged durations. Pollen or pollen substitutes fed to the colo nies, although not =20 generally used by the bee keepers surveyed by the CCD Working Group, =20 may offer some relief to migratory beekeeping and the potential =20 problems that could result from prolonged use of colonies on a single =20= crop, but care must be taken. Pollen can be a route for transmission =20 of diseases, so only properly treated and sterilized pollen should be =20= used. Pollen substitutes that use soy flour as the main source of =20 protein are not as well accepted, nor as nutritious, as pollen substi =20= tutes that avoid the use of soy flour (Saffari et al. 2004). Some soy =20= flours seem to contain anti-feedant compounds that detract from their =20= palatability to honeybees. The problems that mite parasitosis pose to beekeeping are the same in =20= Canada as in the USA. Varroa infestations have lethal conse=ADquences, =20= and must be kept in check. Although varroa is recognized as the major =20= problem, tracheal mites are still very much around. Their presence in =20= the breathing tubes of honeybees has bee