Thunder Bay beekeepers are mobilizing against a serious threat to honey bees after the “varroa” mite was discovered in the city last weekend.

The parasite weakens bee colonies and is connected to the death of honeybees around the world. The head of the Thunder Bay Beekeepers Association said the next step is to find out if — and where — the mite has spread.

Healthy bee colonies like this one could be threatened by a parasitic mite recently discovered in a Thunder Bay yard. (Barry Tabor)

“The biggest thing right now is we need to know every single beekeeper in Thunder Bay,” Barry Tabor said. “We need to know where every single colony is.”

The mite was found in low concentrations in one yard in Thunder Bay. The parasite lives on the honey bee, weakens the colony and is connected to "colony collapse.” Tabor said it’s hard for bees to fight off disease.

He noted beekeepers in the city have worked hard to keep this area mite free for years. There's been an unwritten rule that people shouldn’t bring in bees from outside of Thunder Bay.

"It's an extremely sad day for Thunder Bay and for Thunder Bay bees and beekeepers,” Tabor said, adding the community needs to band together to address the problem.

Ongoing testing will be required to find out whether the mite has spread to other areas.

To facilitate that, however, every single beekeeper and every colony needs to be identified in Thunder Bay. They are supposed to be registered with the Ontario Ministry of Agriculture, Food and Rural Affairs, but Tabor said he knows some people are not registered. He's asking everyone to contact the beekeeping Association.

It's estimated that there are about 500 bee colonies in the city.