CAUSES

The problem is that there doesn’t seem to be a single smoking gun behind CCD but a range of possible causes, including:

Global warming

Global warming causes flowers to bloom earlier or later than usual. When pollinators come out of hibernation, the flowers that provide the food they need to start to start the season has already bloomed.

Pesticide (neonicotinoids, a neuroactive chemical)

It’s not that the pesticides which are aimed at other insects are killing the bees outright. Rather that sublethal exposure of pesticides in nectar and pollen may be interfering with the honeybees internal radar, preventing them from gathering pollen and returning safely to the hive.

Varroa mite - parasites

European foulbrood (A bacterial disease that is increasingly being detected in U.S. bee colonies) microsporidian fungus Nosema.