Why are bee populations falling? We don’t really know, so we don’t really care…

The public has become immune to dire warnings about what falling pollinator numbers could mean for the world’s food supply – because there is no clear solution to the problem, says Oxford researcher Dr Leila Battison.

There is no shortage of concerning studies and articles about colony collapse disorder, the global phenomenon which has seen numbers of bees (and other pollinating insects) fall sharply in recent years. There are plenty of theories circulating – and most agree there is a range of factors contributing to the problem, including climate change, pesticide use, expanding human settlement, and disease – but no consensus when it comes to definite cause and effect.

“We are becoming immune to the many news reports of dropping pollinator numbers. People want to be presented with a clear problem and a definitive solution, but that is hard to do when we don’t yet fully understand the effects of our actions on insect populations,” said Dr Battison, commenting on her article on the topic in Statistics Views.

Shrinking bee numbers have prompted fears of food shortages, as more than a third of global food production relies on animal pollination, largely by honeybees. And recent research has suggested that the more dependent crops are on pollinators, the less stable their yields. In addition to fruit and vegetable crops, beef and dairy could also be affected, as feed crops like alfalfa and clover rely on bee pollination.

But even colony collapse disorder fails to completely explain their declining numbers.

In Europe, large solitary bumblebees are thought to contribute about €22bn a year to agriculture, but nearly a quarter face extinction, wrote Battison. Unaffected by colony collapse disorder, these bees are still at risk from agricultural changes and extreme weather.

“There is no definite course of action for policy-makers, while the voting public also crave simple links and simple solutions,” she wrote. “We are unable to say ‘Bees are killed by X, so we should stop X’, and so this critical threat to biodiversity and food security still advances unaddressed.

“It is clear that additional data and meta-analysis are required to isolate the most significant factors, and perhaps we should adopt a precautionary principle and take action to protect, not exploit, our planet’s biodiversity before we reach a point of no return for our overstretched insect workforce.”