Flowers may endanger bees, serve as parasite hubs

Flowers can pose a grave danger to bees by proving to be a platform for parasites that would infect visiting bees, new research has found.

"Flowers are hotspots for parasite spread between and within pollinator populations," said the study's first author Peter Graystock, a post-doctoral researcher at University of California, Riverside.

"Both the flower and bee species play a role in how likely parasite dispersal will occur," Graystock noted.

The study showed that not only can bees disperse parasites around the environment but also that flowers are platforms for a host of pollinator parasites subsequently dispersed onto visiting bees.

"By showing that visits from parasite-carrying bees can turn flowers into parasite platforms, we can say that it is likely that heavily visited flowers may become more 'dirty' with bee parasites," Graystock noted.

"Planting more flowers would provide bees with more options, and parasite spread may thus be reduced," Graystock said.

The researchers found four common honey bee and bumblebee parasites to be dispersed via flowers: Nosema apis (causes a honey bee disease), Nosema ceranae (causes an emergent disease in honey bees and bumblebees), Crithidia bombi (causes a bumblebee disease) and Apicystis bombi (mostly found in bumblebees).

These parasites are known to cause lethargy, dysentery, colony collapse, and queen death in heavily-infected bees.

The study was published online in the journal Proceedings of the Royal Society B.