Why it's happening
There have been many theories about the cause of CCD, but the researchers who are leading the effort to find out why are now focused on these factors:
- increased losses due to the invasive varroa mite (a pest of honeybees);
- new or emerging diseases such as Israeli Acute Paralysis virus and the gut parasite Nosema;
- pesticide poisoning through exposure to pesticides applied to crops or for in-hive insect or mite control;
- bee management stress;
- foraging habitat modification
- inadequate forage/poor nutrition and
- potential immune-suppressing stress on bees caused by one or a combination of factors identified above.
Additional factors may include poor nutrition, drought, and migratory stress brought about by the increased need to move bee colonies long distances to provide pollination services.