A new chemical compound discovered by researchers at Simon Fraser University could help bees around the world fight off deadly infestations of mites.
Led by chemistry professor Erika Plettner, SFU researchers and members of the beekeeping industry are now testing the potential treatment in apiaries in British Columbia and Alberta.
“We’ve discovered a substance that can paralyze the mites and possibly kill them, and it doesn’t seem to have too much of an effect on the bees. These field trials are very important to demonstrate efficacy in colonies and are the next step towards actual use of the treatment,” says Plettner.
At one of the South Surrey trial sites, researchers are conducting a randomized trial involving 40 bee colonies that have been exposed to varroa mites.
A deadly parasite of bees, varroa is a worldwide problem for beekeepers.
Once they infiltrate a colony, the pests feed on bees, stinging them, injuring them and making them susceptible to secondary diseases.
If left to become infected, the mites can wipe out entire colonies during the winter months.
“In terms of the scale of the problem, it’s global,” says Plettner. “In Canada, we experience colony loss every year due to a variety of causes during overwintering, but mite weakness is definitely a factor.”
There are currently a limited number of chemical treatments, but the mites are starting to show signs of resistance. New treatments must therefore be added to the range of options available to protect bee colonies in the long term.
The compound tested by SFU is codenamed 3C36.
“Like many discoveries, it was a fluke,” says Plettner. “We discovered this substance as part of a large screen we made to feed moth larvae deterrents. It was the best we found, so when we started working with bees, it made sense to test this stuff on mites.
So far, Plettner says the results are encouraging.
Researchers lay sticky sheets with a grid under the test colonies and regularly sift through any material that falls to the bottom of a hive.
They document and compare the number of dead mites found in hives randomly treated with 3C36, a control substance (one of the currently approved treatments) and those that are not treated.
“The sticky leaves under the hives help us take a snapshot of what’s falling and we can take it back to the lab, put it under a microscope and count it,” says Plettner. “It’s very promising. We noticed that our compound causes a greater drop of mites than the control group.
If the team continues to see success, they plan to seek licensing partners and gain federal approval for the compound to be deemed safe to use.
“At this stage, Varroa management is a reality of beekeeping. In order to do this successfully and not lose our tools of resistance – which is only part of evolution – we have to use different tools over the years,” Plettner said. “Having very sick bees is also not a good thing for other insects, because the viral diseases that vector mites can spread. This is why, as beekeepers, we have a responsibility to ensure that our bees are healthy.