Does a cure for Bee Colony Collapse end the threat?

A recent article in ScienceDaily (Apr. 14, 2009) reported that scientists have isolated the parasite Nosema ceranae from professional apiaries suffering from honey bee colony collapse syndrome. The article also said that the scientists had successfully treated infected colonies with Fumagillin, a fungal metabolite that suppresses the formation of new blood vessels.

What's all this mean?

There are a couple of different takes:

First of all, western beekeepers have been battling a different nosema parasite quite a while: Nosema apis. This critter used to be thought of as a protozoan that got into a bee's gut and weakened it to the point of death. But more recent studies have now classified it as a microsporidian: A single-celled fungal-like creature that reproduces with spores. Beekeepers really fear Nosema apis because it severely reduces the viability of a colony, and because its spores are really long-lasting and resistant to freezing -- meaning that successfully over-wintering a colony won't bring relief. Scientists now believe that the bees become infected by eating honey that contains the Nosema apis spores.

Fumagillin had been previously shown to be an effective means of controlling and/or curing Nosema apis. But it's a powerful antibiotic agent that interrupts the cycle by preventing by blocking blood vessel formation. It does this by binding to an enzyme called methionine aminopeptidase. Sort of like deep magical poison. Fumagillin is also used as an experimental anti-cancer drug.

What's curious is that Nosema ceranae -- the completely different microsporidian -- has now been finally identified as the parasite that has been behind colony collapse disorder.

Nosema ceranae is a much more recently discovered pest. Some say that it has existed in the Eastern honey bee Apis cerana for some time, but it was only first discovered in Western honey bee populations in Spain in 1996.

This would suggest that it made a species jump relatively recently -- as little as ten years ago -- and that could be why it's been so virulent: The Western honey bee Apis mellifera has not yet developed any immunity or resistence. If Fumagillin does, in fact, work, it's great news in the short run. But it's not the best news one could hope for.

Why?

The world's dependency on the Western honey bee Apis mellifera for pollination has really gotten out of hand.

Agriculturalists will always tell you that crop monoculture is dangerous to the ecology because it concentrates an environment that permit pests to evolve to specialize and take advantage of the niche'. We saw this in the wine industry with Phylloxera.

Today U.S. crops are now heavily dependent upon a different sort of monoculture: The pollinating capacity of the Western honey bee Apis mellifera.

How is this being manifested?

Thirty years ago, when I first became involved with beekeeping, the number of bee pests were significantly fewer. The Tracheal mite Acarapis woodi was not known in the U.S., though it had appeared on the Isle of Wight. It arrived here in the early 1980s. Varroa mites Varroa destructor were not in the U.S. until 1987. All that beekeepers had to deal with back then were American Foul Brood, European Foul Brood, Chalk Brood and wax moths.

Most of the diseases that beekeepers of Apis melliara are seeing seem to be as the result of contact with Apis cerana: The Asiatic honey bee or also known as the Eastern honey bee or the Indian honey bee. This Eastern honey bee isn't as productive as the Western honey bee, but it's been quasi-domesticated for just as long, kept on farms in wooden logs, or more recently in hive bodies. This bee co-evolved with Tracheal mites and Varroa mites, and consequently has managed to build up evolutionary grooming behaviors that help keep the colonies healthy.

So it appears that the more recent problems associated with bee diseases is really a genetic problem that has resulted from the contact of different bees species beyond their naturally occurring ranges.

The downside of this is that the use of pesticides or fungicides may halt a particular disease in a particular colony, but it's not helping the species develop resistance or behavioral modifications that can prevent future problems.

There has been significant work done, however, in creating hybrid bees: Bees that are crossed to create genetically resistant strains.

For instance, the bees that we will be getting are a Carniolan/Yugoslavian cross that is said to be more inherently resistant to Varroa mites. The queen of one variety was artificially inseminated with sperm from a different variety: In this case, Carniolan queen with a Yugoslavian drone. This process is done over at Honey Bee Genetics nearby.

However, another interesting thing that has been documented is that the vitality of queen bees themselves has been seriously diminished -- though it's unclear what the cause might be.

Thirty years ago, it was expected that a queen would be viable in a colony for an average of two years. I'm learning, through reading, that today the viability of a queen is often less than one year, and that re-queening mid year is not uncommon at all.

When you stop to realize that our entire food supply is dependent upon the pollinating capabilities of Apis mellifera, it's a sobering thought about how quickly this dependency could unravel our entire food chain.