Decline of wild pollinators 'alarming'
Friday 1 Mar 2013 8:34 a.m.
Honeybees have been estimated to contribute $5 billion to New Zealand's economy through their pollination work
The under-fire honeybee may be getting the headlines, but it may be the decline of wild pollinators – unheralded for their more effective pollination work – poses a more alarming threat to food production, say scientists.
A massive international study, of 41 major crops on six continents and including data from New Zealand, shows wild insects are better at pollinating crops than bees, and managed bee hives cannot replace the work of their wild counterparts.
Without steps to conserve wild species and protect their habitats, the ongoing loss of wild insects is destined to compromise agricultural yields worldwide, says Argentina's Black River National University's Lucas Garibaldi.
Honeybees have been estimated to contribute $5 billion to New Zealand's economy through their pollination work. However, they are under threat from the likes of the varroa bee mite and colony collapse disorder.
New Zealand Plant & Food Research scientist Brad Howlett, a co-author on the study, says a wide variety of fly and bee species contribute to the pollination of onions, and many other crops, such as brassica, carrot, radish and kiwifruit.
There are currently no management procedures for better utilising these insects, he said.
"Increasing pollinator diversity within crops can lead to better yields because it increases the abundance of efficient pollinators that can be active under weather conditions that are less suitable to honeybees."
Another Plant & Food Research scientist David Pattemore says relying on a single managed pollinator "is not in the best interests of New Zealand Inc".
Scientists were preparing a major proposal to develop methods to manage free-living bumblebee populations in orchard environments, he said.
"A more diversified approach to pollination will increase yields of higher quality fruit and seeds, thus leading to an economic gain for growers and New Zealand."