ALMOST one-third of Scotland's managed bee colonies were wiped out during the winter as icy conditions played havoc on already fragile populations.

Academics have warned of major concerns for bee numbers north of the Border and say the sudden loss of so many colonies will have a knock-on effect on the agricultural industry.

Bees play a vital role in the food chain as they pollinate crops and help increase farm yields, and the academics said they feared a drop-off in numbers could lead to smaller harvests and rising food prices.

A survey, by Strathclyde ­University academics on behalf of the Scottish Beekeepers' Association, found 31.3% of managed honey bee colonies in Scotland failed to survive last winter, almost double the previous year's loss rate of 15.9%.

In total, 156 colonies were lost during the winter of 2012/13 out of a total of 498 colonies managed by beekeepers who took part in the survey. A further 67 beekeepers also reported losing at least some of their colonies between October 1, 2012. and April 1, 2013.

The study was compiled by Dr Alison Gray and Magnus Peterson, of Strathclyde University's department of mathematics and statistics.

Ms Gray said: "This is an extremely high loss rate. The loss rate last winter is the highest we have found since these surveys began in 2006 - and is similar to that over the winter of 2009/10, when we estimate 30.9% of colonies were lost.

"Results from European colleagues show the loss rate in Scotland is among the highest in Europe this year, while similarly high losses have been reported recently from England and Wales."

The survey was compiled from data supplied by 300 members of the Scottish Beekeepers' Association, which represents most of the country's 1300 beekeepers.

Ms Gray added that loss of bees in Scotland was mirrored around the globe. She said: "Honey bees worldwide are having to contend with habitat loss and reduction in variety of forage sources due to pressures of intensifying land use, increasing spread of new and old pests - caused by globalisation of trade in bees and bee products - as well as possible adverse effects of agricultural pesticides.

"For bees in northern Europe, poor weather conditions - combined with these various other factors that impact adversely on bees - are making beekeeping a challenge and survival difficult for honey bees generally.

"The difficult weather ­conditions are a particular problem in Scotland, with severe winters followed by long, cold wet springs being a problem, especially if it comes after a poor wet summer as in this past year."

The weather also took its toll on wild honey bee populations, with 11 out of 20 colonies known to be alive last September now thought to have died.

Mr Peterson said: "The latest results indicate a low survival rate, of just 45%, among feral colonies over this last winter. This is the worst winter survival rate among the feral colonies known to the volunteers since they started monitoring them five years ago."

In April, Rural Affairs Secretary Richard Lochhead announced the Scottish Government was making £200,000 available to help commercial bee farmers restock and rebuild colonies devastated by prolonged winter weather conditions. It was in addition to £500,000 of funding for livestock farmers whose herds were devastated.

The harsh winter and delayed start to spring has affected several species this year, with the RSPB previously warning about the impact on birds. Numbers of the long-tailed tit, one of Scotland's most popular garden birds, declined by two-thirds as it was affected by the cold temperatures and needs to eat plenty and often to survive the freezing nights.

Butterflies also emerged weeks later than usual as a result of the cold spring, with rare spring species such as grizzled skippers, pearl-bordered fritillaries and wood whites emerging up to a month later than normal.