Disclaimer: I've done very little research on this. I'm simply putting out some thoughts that I believe should be investigated. The small amount of research I've done is very limited and I am by no means an expert or even a particularly well informed amateur.
World Net Daily ran an article titled Buzz Kill!. The article was about the phenomenon of sudden deaths of honey bees world wide. This isn't the first time I've seen articles on this as the problem has been growing for the last several years. I have a hypothesis as to what is causing the problem. I think that the wide spread use of Genetically Modified Organisms or GMO's may be to blame.
Basically a GMO or GEO (Genetically Engineered Organism) is any plant or animal that has been genetically altered by man made methods. This is done with crops for many reasons like enhancing a crops resistance to herbicides, insecticides and pests. The reasons seem very logical. A crop, like corn or wheat that is altered can be planted in a field that has been heavily sprayed with a product like Round Up. The round up will kill the weeds and increase the yield of the crop. A higher yield means better profit per acre. The concept is similar with insecticides and making a crop resistant to pests.
Scientific testing of the effects of GMO crops is very limited. The industry has limited regulations and there is little governmental or popular support for enhanced regulation, testing or product labeling. Agra business is keen to avoid all product labeling for a variety of reasons. This is a link to a anti GMO activist web site for those of you interested in more info. Here is a link to some more scholarly articles.
One of the things we do know is that GMO crops can have effects on mammals. If that is the case and some of the reasons for using GMO's is there effect on bacteria, chemical, viral and insects as it relates to plant health, it seems plausible that the use of GMO plants could have a negative effect on on non-target species, either as a result of coming into direct contact or as a unintended consequence of cross contamination.
If I had the time/resources I would pursue this. Since I don't, I would be interested in the thoughts of others on the topic. I know that some experts (Farmer Tom) and some possibly interested amateurs stop in here from time to time. Both opinions and any links to information are welcome.