Australasian Science: Australia's authority on science since 1938

Fungus Fouls Bee Semen

A widespread fungus (Nosema apis) that causes dysentery in honey bees can be sexually transmitted from sick male bees to virgin queens.

Prof Boris Baer of The University of Western Australia said the discovery, published in Scientific Reports, had major consequences for breeding programs.

“To this point, semen used for artificial insemination has typically been regarded as safe, and has been freely shipped around the world,” he said. “This finding questions this practice. It calls for additional tests on the semen to avoid spreading the disease across Australia and internationally.”

The researchers found that it takes 3 weeks until the sperm quality of sick males is affected and they start dying from the disease. Baer says this “gives them time to fly from the hive and mate, transmitting the fungus to virgin queens who, once impregnated, transport it home to their own hives with potentially catastrophic results”.

The scientists glued radio frequency tags onto the backs of honey bee workers, revealing that sick bees are less likely to leave the hive to forage and carry less pollen when coming back.