Did we ever figure out what is causing colony colapse disorder ?

Not exactly. They think it might be insecticides or bee mites. And it affects all American bees, or seems to, as well as bumble bees.

The consensus seems to be that a combination of maladies is now afflicting honeybees. Everything from rampaging mites through the introduction of new neonicotinoid pesticides. The mite problem was recognized for decades, but the new insecticides were the knockout punch for the already stressed honeybees. The widespread use of the neonicotinoids on soybean fields coincided with an immediate and documented epidemic of unprecedented levels of lethality in commercial honeybee hives.

@kritiper When you say American bees do you mean all bees currently found in America? Or, specifically bees native to North America? I think bee keepers often use a European honey bee in America, but I’m not sure. I know the African bees were brought to the Americas (Brazil specifically) for their honey production, I’m pretty pissed off about it. Have the African, or Africanized bees, not suffered hive collapse like the other bees found in America now?

@JLeslie I meant, for the most part, native bees. Bee keepers are doing studies now in the US with Australian bees.
I haven’t heard about Africanized bees, and I doubt anyone cares since they don’t do pollinating and honey making like other bees. And African bees were not brought into the Americas to make honey, I think they were being researched as to their honey and other potentials, and the little buggers escaped!
But I believe all types of bees are being affected by the problem, which is the insecticides being used. The bees leave the hive to find pollen but can’t find their way back to the hive afterwards.

You’re right. All of the honeybees are catching hell, and the killer bees are no exception. And it isn’t just honeybees. Other pollenating insects are “dropping like flies” from these lethal new insecticides The good news regarding the Africanized “killer bees” is that I read a while ago that their aggressive tendencies are diminishing quickly as they continually interbreed with their more docile new world cousins.

Thanks for the info.