For years reports of a seemingly unstoppable decline in honey bee populations have repeatedly appeared in the media around the world.

With populations in Europe and North America declining sharply the term ‘colony collapse disorder’ (CCD) has been coined by those trying to explain the problem. Everything from fungi to climate change to farming practices have been considered as the culprit. The decline in commercially-reared bees has led to warnings of a ‘polinator crisis’ with world crops under threat from a mass insect die off.

But is there really a global problem? And if so, what is the cause?

A new report from the United Nations Environment Programme says that currently available data “are not sufficiently conclusive to demonstrate that there is a worldwide pollinator and crop production crisis”, although declines have been observed in Europe and North America. Even in those regions, “CCD only accounts for about 7% of losses in the USA and even less in Europe” it says.

However the report’s authors argue that we should do more to encourage farmers to restore flowering plants and other habitats that promote bees and other pollinators and to take more care in the choice and application of pesticides. After all, we do rely on insects to pollinate many of the plants we eat (71 of the 100 crops that produce 90% of food worldwide, according to the UNEP).

“Human beings have fabricated the illusion that in the 21st century they have the technological prowess to be independent of nature,” says Achim Steiner, executive director of the UNEP (press release). “Bees underline the reality that we are more, not less dependent on nature’s services in a world of close to seven billion people.”

The UNEP report says that pretty much every factor considered is probably to some extent to blame in presenting a growing threat to all insect pollinators. It notes problems with invasive species of parasitic mites, habitat degradation, pesticide use, globalisation of bee keeping potentially spreading diseases and climate change, among other issues (see list below or the report for the full breakdown).

“This report underlines that a variety of factors are making … man-made colonies increasingly vulnerable to decline and collapse,” says report author Peter Neumann of the Swiss Bee Research Centre. “We need to get smarter about how we manage these hives, but perhaps more importantly, we need to better manage the landscape beyond, in order to cost-effectively recover wild bee populations to far healthier and more sustainable levels.”

Factors identified by UNEP as threats to insect populations

Habitat deterioration

– Degradation

– Increased pathologies

– Invasive species

– Pollution and other threats

Agriculture practices

– Chemical spraying

– Systemic insecticides

Beekeeping activities

– Health

– Chemical use

– Diet

– Transport

– Colony splitting and selection

Climate change

Image: photo by Jason via Flickr under creative commons.