Honeybee populations have been declining for a combination of interacting factors. There is the parasitic Varroa mite that spreads disease; there is widespread exposure to pesticides; there is diminishing natural forage and nesting habitats as land is developed; and there is climate change.
Researchers at Oxford University looked at the impact of climate change and land use changes on the floral diversity honeybees need to thrive. Pollen, which forms much of their diet, contains specific lipids called sterols that are necessary for the bees’ development. But there is increasingly too little of the pollen they need.
Many beekeepers feed artificial pollen substitutes to their bees, but these commercial substitutes lack the necessary sterol compounds, making them nutritionally incomplete.
The Oxford researchers, along with several collaborators, succeeded in engineering a specific yeast species that produces a precise mixture of six key sterols that bees need. This mixture was incorporated into diets fed to bees over a three-month trial in which the bees were kept in enclosed greenhouses and fed only the treatment diet.
Colonies fed with the treatment diet reared up to 15 times more larvae compared with control diets. The sterol profile of larvae fed the engineered yeast matched that found in naturally foraged colonies, showing that the bees selectively transfer only the biologically important sterols to their young.
Further large-scale trials are needed to assess the long-term impacts on colony health and reproduction. Potentially, the supplement could be available to beekeepers within two years.
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Saving bees with ‘superfoods’: new engineered supplement found to boost colony reproduction
Photo, posted August 5, 2012, courtesy of Jennifer C. via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio
