Biologists at UC San Diego have discovered that a tiny single-celled parasite may have a greater-than expected impact on honey bee colonies, which have been undergoing mysterious declines worldwide for the past decade.
In this week’s issue of the journal PLOS ONE, the scientists report that a microsporidian calledNosema ceranae, which has been known to infect adult Asiatic and European honey bees, can also infect honeybee larvae. They also discovered that honey bee larvae infected with the microsporidian have reduced lifespans as adults.
Since 2006, beekeepers in North America and Europe have lost about one-third of their managed bee colonies each year due to “colony collapse disorder.” While the exact cause is unknown, scientists have speculated that pesticides, pathogens, mites and certain beekeeping practices have all contributed to this decline. Nosema ceranae, a kind of fungal pathogen spread by spores, is also implicated in colony collapse because it reduces colony health and is widespread.