NEW DELHI: Wild bees,
butterflies, flies, beetles and other wild insects play a key role in
pollination and hence in food production, a new study of 41 crops in 600
fields across the world shows.
Declining populations of these insects is irreparably harming food production. Till now, the general perception was that honey-bees - that is, domesticated bees - are the only crucial pollinator that is suffering a decline. But this study published in the scientific journal Science upturns current wisdom and clearly shows that it is other insects, including wild bees that do the bulk of pollination.
The study found that these wild pollinators were twice as effective as honeybees in pollinating crops like oilseed rape, coffee, onions, almonds, tomatoes and strawberries. Fruits or seeds will appear on plants only after pollination. No amount of replacement by honey-bees will compensate for the loss of food the study indicates.
About three quarters of global food production is dependent on pollination. Earlier studies had shown that declining honey-bee and farmland bird populations were affecting pollination. Environmentalists have raised serious concerns about the collapse of honey bee colonies due to pesticides and diseases.
"We found that in landscapes with lower diversity and lower abundance of wild insects, the crops set less seeds and less fruit," said Lucas Garibaldi of the National University in Rio Negro, Argentina, who led the 46-member scientific team. "We know wild insects are declining so we need to start focusing on them. Without such changes, the ongoing loss is destined to compromise agricultural yields worldwide."
Garibaldi warned that dependence on one species like honeybees was a "highly risky strategy" because disease can hit and decimate a single species. Studies have shown that the varroa mite has singlehandedly been responsible for killing off honey bees. He also said that a single species will not be able to adapt to climatic changes. A range of wild pollinators are better able to effect pollination because they use a range of methods, visit more plants and collectively are more robust.
Another study published in the same issue of Science showed that more than half the wild bee species were lost in the 20th century in the US. Scientists compared data collected between 1888 and 1891 by entomologist Charles Robertson with data from 1971-72 and new data from 2009-10 and found that reduction in habitat (forests)and a mismatch between flowering times and bees' activity times killed off half of the 109 species recorded by Robertson.
Declining populations of these insects is irreparably harming food production. Till now, the general perception was that honey-bees - that is, domesticated bees - are the only crucial pollinator that is suffering a decline. But this study published in the scientific journal Science upturns current wisdom and clearly shows that it is other insects, including wild bees that do the bulk of pollination.
The study found that these wild pollinators were twice as effective as honeybees in pollinating crops like oilseed rape, coffee, onions, almonds, tomatoes and strawberries. Fruits or seeds will appear on plants only after pollination. No amount of replacement by honey-bees will compensate for the loss of food the study indicates.
About three quarters of global food production is dependent on pollination. Earlier studies had shown that declining honey-bee and farmland bird populations were affecting pollination. Environmentalists have raised serious concerns about the collapse of honey bee colonies due to pesticides and diseases.
"We found that in landscapes with lower diversity and lower abundance of wild insects, the crops set less seeds and less fruit," said Lucas Garibaldi of the National University in Rio Negro, Argentina, who led the 46-member scientific team. "We know wild insects are declining so we need to start focusing on them. Without such changes, the ongoing loss is destined to compromise agricultural yields worldwide."
Garibaldi warned that dependence on one species like honeybees was a "highly risky strategy" because disease can hit and decimate a single species. Studies have shown that the varroa mite has singlehandedly been responsible for killing off honey bees. He also said that a single species will not be able to adapt to climatic changes. A range of wild pollinators are better able to effect pollination because they use a range of methods, visit more plants and collectively are more robust.
Another study published in the same issue of Science showed that more than half the wild bee species were lost in the 20th century in the US. Scientists compared data collected between 1888 and 1891 by entomologist Charles Robertson with data from 1971-72 and new data from 2009-10 and found that reduction in habitat (forests)and a mismatch between flowering times and bees' activity times killed off half of the 109 species recorded by Robertson.
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