MORE THAN a third of the commercial honeybees died during the winter of 2009-10, showed the annual survey data released by the US Agricultural Research Service.
This is a continuous drop in the past three years. Several European and Asian countries have also reported losses at the American scale for the past three years. Beekeepers are worried because bee colonies naturally lose 5 per cent of their population annually, but since 2006 they have been losing 30 to 90 per cent of their population a year.
It is estimated a third of the food we eat solely depends on honeybees for pollination; the insect contributes about US $38 billion to the global economy. “Bees contribute to global food security and their extinction would represent a terrible biological disaster,” said Bernard Vallat, director general of the World Organization for Animal Health, or OIE. The intergovernmental organization headquartered in Paris has recently prioritized research on bee mortality.
It said the catastrophic fall in bee numbers is not due to any single factor. Parasitic, bacterial and viral infections, exposure to pesticides and radiation from mobiles, poor nutrition and global warming are all concomitant factors that threaten the survival of honeybee colonies worldwide (see box). Since knowledge on bee diseases is insufficient, OIE has called on the international community to intensify research on how to fight the emerging and known diseases.
India is at high risk
Agricultural economies like India are at high risk from the bee decline. Of the 160 million hectares (ha) cropped area in India, some 55 million ha depends on honeybees for pollination, said Shashidhar Viraktamath, professor at the University of Agricultural Sciences in Dharwad, Karnataka. Without them India’s food production will reduce by one-third, he cautioned.
Several bee research projects are under way with funding from the All India Coordinated Project on Honey Bees and Pollinators and by institutions like Panjab University in Punjab. The researches show the bee population in India is declining, but there is no information on the extent. “The institutions do not coordinate and most focus on beekeeping, honey and wax production,” said Viraktamath. “The role of bee pollination is largely ignored.”
K R Shivanna, fellow of the Ashoka Trust for Research in Ecology, a nonprofit in Bengaluru, agreed. “I can hardly recollect any studies on the impact of decline in bee population on crop productivity in India,” Shivanna said. “There is an urgent need to initiate research on these aspects to develop strategies to sustain crop productivity,” he added.
How to woo the bee?
Viraktamath suggests shifting to organic farming could save the bees. But Tim Benton, biologist at University of Leeds in the UK, said benefits to biodiversity from organic farming are much lower than believed; it is 12 per cent more than the conventional farming. Organic farms also yield less than half of the conventional farms, Benton said in Ecology Letters on May 5.
He blamed the decline on monoculture as it restricts bee’s food resources. James Tew, entomologist at Ohio State University in USA, suggests limiting habitat destruction. “We are in an ironic situation. With the growing population, the world needs more food and thus more pollinators and farmland,” Tew said. “While expanding farmland, man is destroying natural habitat as well as the pollinators.”