There are signs that there have been “significant losses” in bee colonies this year, the Department for Environment, Food and Rural Affairs (Defra) said.

Investigations by the National Bee Unit, which has monitored bee colony losses since last year, are being given priority because of concerns about high death rates.

Bees play an important role in agriculture, with the value of commercial crops that benefit from bee pollination estimated at £100 million to £200 million a year. The honey industry is worth beween £10 million and £30 million. But bee populations face a growing number of threats, including pests and diseases such as the varroa mite.

In 2007 high losses in Britain of about 18 per cent were thought to be the result of inadequate management of hives in coping with varroa, poor husbandry and high levels of parasites and viruses. This year survival could be affected by last year’s wet summer.

Beekeepers who experience significant colony losses are being urged to contact their local bee inspector to arrange a visit. If no immediate explanation for the loss can be found on site, samples will be sent to the National Bee Unit for testing, Defra said.

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