Pesticides put bee colonies at risk: study Bee deaths Pesticides
used in farming are also killing worker bees and damaging their
ability to gather food, meaning colonies that are vital for
plant pollination are more likely to fail when they are used,
according to a new study. "Here we show that chronic exposure of
bumblebees to two pesticides ... impairs natural foraging
behaviour and increases worker mortality leading to significant
reductions in brood development and colony success," write Gill
and team. The United Nations has estimated that a third of all
plant-based foods eaten by people depend on bee pollination and
scientists have been baffled by plummeting numbers of bees,
mainly in North America and Europe, in recent years. Gill says
previous studies have mostly examined the impact of pesticides
on individual bees, but his study looked at the impact on bee
colonies. "Although field-level pesticide concentrations can
have subtle or sublethal effects at the individual level, it is
not known whether bee