Monday, August 26, 2013

What's killing the bees?

By now, everyone has heard of the bee problem: bees in North America and Europe are suffering huge losses, a phenomenon known as Colony Collapse Disorder (CCD). Since 2006, beekeepers have been finding their colonies diminished, leaving fewer bees per hive. We rely on honeybees to pollinate a lot of the food we eat, and scientists and beekeepers have been trying to figure out what is causing the collapse.

There have been a lot of news stories about potential causes--pesticides, parasites, disease...all of these things kill bees but no one has really tracked down the root of the problem. Neonicotinoids, a class of pesticides that seem to be harming bees, were banned recently by the EU for 2 years. However, that might not be the real culprit. There was an article in Time recently that gave a nice overview of the possible causes, and I'm going to summarize that here.

Neonicotinoids (pesticides)  
Evidence for:        
-present on pollen and bees
-highly toxic to bees            
-can be absorbed from the soil
-persist for years after application

Evidence against:
-no direct link to CCD
-France has restricted use since 1999, and still has CCD
-Australia uses, and doesn't have high CCD rates

Varroa mite  (parasite)                                      
Evidence for:
-demonstrated bee killer

Evidence against:
 -not all CCD hives have mites

Fungal infections                                                   
Evidence for:
-known to kill bees              

Evidence against:
-not all CCD hives have infections

While pesticides no doubt are harmful to bees, we don't have enough evidence to conclude that pesticides cause CCD. Still, it's enough to make me want to eat organic. The other scary thing to think about is the fact that North America's native bees, such as bumblebees, have no keepers replenishing their colonies or taking care of them Bumblebees are also dying off in massive numbers. Why???

There is a lot more information out there on this topic. Here are a few links:

http://www.xerces.org/neonicotinoids-and-bees/
http://www.ars.usda.gov/News/docs.htm?docid=15572

No comments:

Post a Comment