BROOKS, Alta. — Insurance policies can take many forms. Some of them fly and pollinate crops.
That’s how ecologist Mark Wonneck of Agriculture Canada views wild bees.
With all the public attention focused on honeybees, relatively little is aimed at Canada’s 960 species of wild bees.
“This is kind of like an insurance policy, having wild pollinators out there, too,” Wonneck told a March 18 pest surveillance branch update in Brooks.
Alberta has 90 to 100 species of wild bees, yet most of the attention goes to honeybees and leafcutter bees.
“It’s probably reasonably true that in agricultural areas where so much of the habitat, especially where lots of annual cropping makes up a big part of the landscape, that populations (of wild bees) are definitely down relative to where there’s more habitat available.”
Wonneck said most wild species do not travel far from their nests, so habitat should be no more than 150 metres from the crop that requires pollination.
Seventy percent of wild bee species nest underground, and unlike their honeybee relatives, most wild bees are solitary.
If possible, habitat on field margins should be at least seven to 10 metres wide, with maximum sun exposure to encourage a variety of wild flowers.
Pesticides should be the pest control of last resort if wild bees are to be protected, Wonneck said. They tend to fly earlier than honeybees and will continue in colder and wetter weather, which makes them more vulnerable to pesticide spraying.