08/30/2013 06:04 EDT | Updated 10/30/2013 05:12 EDT

Invasive alien fly threatens Nova Scotia berries

Farmers across Nova Scotia are grappling with a fruit fly-like insect that has the potential to destroy berry crops in the province.

The spotted wing drosophila is an invasive alien vinegar fly, native to Asia, and is closely related to what is commonly known as a fruit fly. The insect, which has turned up in all three Maritime provinces, inflicted $2.2 million in damage to the British Columbia cherry industry in 2010.

Blackberries, raspberries and blueberries are ripe for picking, but farmers like Bob Kidston say they are fighting an army they can hardly see.

“We hired an extra 250 pickers this year just to keep our fruit harvested you know when it’s ready and then get back in there again and get it off before the fruit flies are back at it again,” said the Sheffield Mills farmer.

The spotted wing drosophila lays eggs in ripening fruit making it soft and unusable for market. It will attack fruit such as raspberries, blackberries, blueberries, strawberries, cherries, plum, peaches, nectarines, and sometimes grapes.

“It could be 40 per cent loss to North America,” said Kidston.

The bugs were first discovered in Nova Scotia two years ago. Since then their population has increased by 50 per cent.

Debra Moreau, an entomologist with Agriculture and Agri-Food Canada, said there's not much farmers can do, other than track them.

“Really good, tight monitoring, trapping, just due diligence. We can sort of keep a handle on where the fly is when it’s moving into the crop and the extent of the problem,” she said.

Kidston said he hasn't found any eggs in his fruit yet, but he fears it's inevitable.

“It's across the whole province. No one is immune.”