GLOBALISATION is killing bees, as the opening up of trade allows pests and diseases to travel swiftly around the world, says a UN study and attempts to arrest declining bee populations are making the problem even worse, the authors found.

Unexplained bee deaths have become an increasing issue in the past five years, a phenomenon labelled colony collapse disorder. Bees in the US, Europe and Asia have been affected, although it is hard to gather reliable data on how many have died.

Some bee colonies die off naturally, chiefly in winter, but the scale of the losses reported by beekeepers has prompted governments and scientists to examine why bees appear to be under threat and to try to solve the problem by changing the ways they are kept.

But attempts to halt the fall in bee numbers through breeding programmes and massing bees in huge hives are exacerbating the problem, a UN official has said. Industrialised hives create ideal breeding conditions for some of the very pests and fungal diseases thought to be responsible for many bee deaths. Moving the hives from farm to farm to encourage pollination spreads the diseases further.

“We are creating the ideal conditions in the man-made hives that promote pests, chemical contamination and other factors,” the official said.

More than a dozen factors are behind the bee deaths, said the UN Environment Programme (Unep) in its report, Global Bee Colony Disorders and Other Threats to Insect Pollinators. These include air pollution, new fast-spreading fungal diseases and varieties of parasites such as the varroa mite, as well as the loss of habitat for wild flowers in intensively farmed areas.

The increased use of pesticides — including broad-spectrum and systemic pesticides, which are absorbed by plants and can be expressed in pollen and nectar - appears to be another important factor, according to the UN. It said that when some pesticides were allowed to combine, they formed a potentially lethal cocktail that could damage bees' sense of direction and memory.

The scientists were unable to pinpoint the most important factors, saying more research was needed. Last year a 10-million-pound British research project was launched to study the decline of bees.

Given the growing global human population, researchers are concerned that the loss in numbers of bees and other pollinating insects could lead to serious problems with food supply. Of the 100 crop species that provide 90 per cent of the world's food, more than 70 are pollinated by bees. Bees contribute about $200 billion a year to the global economy.

Achim Steiner, executive director of Unep, said: “The way humanity manages or mismanages its nature-based assets, including pollinators, will in part define our collective future in the 21st century. Human beings have fabricated the illusion that they have the technological prowess to be independent of nature. Bees underline the reality that we are more, not less dependent on nature's services in a world of close to 7 billion people.”

The report suggested that as many as 20,000 flowering plant species upon which bees depend could become extinct if conservation efforts failed.

Air pollution is also making it harder for bees to find plants — scents that could carry 800 metres in the 19th century may travel only about 200 metres today, impairing bees' ability to find food.—Dawn/Guardian News Service