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Bee death

Bees gather on a partially empty hive at an apiary at Maria Pinto town, some 53 km northwest of Santiago April 18, 2011. The La Nina weather front in Chile is causing a decline in the country's bee population and the honey harvest has consequently fallen by some 60 to 70 percent, according Chile's National Beekeeping Association. Drought conditions alter the flowering patterns of plants, affecting the availability of nectar, which in turn makes survival harder for bees. Picture taken April 18, 2011. REUTERS/Ivan Alvarado

Bee death mystery continues

A common class of pesticide is causing problems for honeybees and bumblebees, important species already in trouble, two studies suggest. But the findings don't explain all the reasons behind a long-running bee decline, and other experts found one of the studies less than convincing.