The percentage of honeybee colonies which made it through this winter was slightly higher than last year despite the harsh conditions, the British Beekeepers' Association said yesterday.

But while there was a "small and encouraging improvement" in survival rates this year, the UK's honeybees were still not healthy enough, the organisation's president Martin Smith warned.

According to figures collected by the BBKA from more than 1,000 of their members, 17.3 per cent of colonies across the UK were lost over the winter.

However, there were significant regional variations, with losses of more than a quarter of colonies (26 per cent) in the north of England compared to just 12.8 in the South West.

Nationwide, the figures were a slight improvement on 2008/2009 when 19.2 per cent of colonies did not make it through the winter and were significantly better than the "disastrous" losses of 2007/2008 when 30.1 per cent did not survive.

Mr Smith said: "It shows our honeybees are slowly moving out of intensive care, but they are still not healthy enough.

"Winter losses between seven per cent and ten per cent are acceptable. The current rate is not and neither are the vast regional differences.

"Yet there is no answer to what is causing the losses. Disease, bad weather and poor nutrition due to habitat loss are the prime suspects."

He called for more research into the causes of declines in honeybees, in order to help sustain the increased survival rates seen this year.

And he said: "British beekeepers are having to work even harder at this time of year to replace their missing colonies to keep the stream of honey flowing and more vitally to maintain the 'pollination army' on which we depend for so much of our food and the beauty of our countryside."

The survey also revealed that beekeepers are taking steps to rebuild bee stocks, with the average number of hives being kept by each keeper rising from 3.7 in 2007 to 4.7 this year.

The BBKA said thousands more people were now taking up the craft of beekeeping, with the association's membership rising from 12,500 to 17,500 in the past two years.

And the number of hives had almost doubled since 2007 to more than 80,000, the BBKA estimates.

Mr Smith added: "It's not just beekeepers who can help bees to recover, everyone can play their part by continuing to plant bee-friendly plants, fruit and vegetables in their window boxes, patio pots, gardens and allotments to provide desperately needed forage."