Global reliance on honeybees for pollination is a risky strategy
Australian scientists say it’s important to consider other pollinators besides bees when deciding on the application of pesticides. Farmers using pesticides that spare bees but kill other insects might be ignoring important sources of crop pollination, the new study found.
“Many crops — including mangoes, custard apples, kiwi fruit, coffee and canola — depended on non-bee insect pollinators such as flies, butterflies, moths, beetles, wasps, ants, and thrips,” said University of Queensland plant ecologist Dr Margie Mayfield.
“Scientists haven’t much broadly explored the role of non-bee insects in crop pollination,” said Dr. Mayfield, who is the Director of the Ecology Centre in UQ’s School of Biological Sciences.
Mayfield said the global reliance on honeybees for pollination is a risky strategy given the threats to the health of managed honeybee populations due to pests and diseases such as Varroa mites and colony collapse disorder.
“Non-bee insects are an insurance against bee population declines. We are trying to get the message out there to use scientific findings such as these to promote a change in agricultural practices,” she said.
The researchers found that non-bee pollinators performed 25 to 50 per cent of the total number of flower visits. Other insects are less effective pollinators, but provide more visits to flowers.
Non-bee insect pollinators had other advantages, said study leader Dr. Romina Rader, with the University of New England, Armidale.
“Fruit set in crops increased with non-bee insect visits, independently of bee visitation rates, indicating that non-bee insects provide a unique benefit not provided by bees.
“We also found that non-bee pollinators were less sensitive to habitat fragmentation than bees.”