Urban hives boom could be 'bad for bees'
A boom in urban beekeeping could be doing the insects more harm than good, say scientists.
Experts warn that dense populations of the bees in areas with few feeding plants adds more pressure to the troubled species.
Honeybee declines have been linked to a lack of suitable habitat so increasing the number of London's hives could exacerbate problems.
They urge nature lovers to plant more flowers rather than adding new hives.
The advice of Professor Francis Ratnieks and Dr Karin Alton, from the Laboratory of Apiculture and Social Insects at the University of Sussex is reported in the Society of Biology's magazine The Biologist.
Last year's bad weather caused dramatic losses of 33.8% of Britain's honeybee colonies over the winter.
But scientists are yet to agree on what is responsible for the continuing declines of honeybee populations.
Charities and conservationists have been championing beekeeping in response to the statistics. The latest figures from the UK's National Bee Unit show the number of hives in London has more than doubled since 2008 to a total of 3745.
In the capital there are now 10 hives per square km, compared with 1 per square km in England as a whole.
Rooftop hives in the city have become increasingly popular as symbols of a company's 'green' credentials or as team-building exercises.
But scientists warn that inexperienced beekeepers could be risking the health of their wards.
"If there are too many colonies in an area, then the food supply will be insufficient. This will mean that colonies do not thrive, and may also affect other species that also visit flowers," explained Prof Ratnieks.
"A high density of colonies kept by novice beekeepers may also provide conditions under which the harmful contagious honeybee disease American foulbrood can spread. This disease is rare in Britain, but epidemics can break out... When a hive is infected with AFB it must be burned."
According to Dr Alton, each new hive in London would need 1 hectare (0.01 square km) of the herb borage to support its honeybees.
Instead, she advised nature lovers to plant flowers where they have space to relieve the pressure on city bees.
"Marjoram, borage, lavender, catmint, and Bowle's Mauve all attract bees, are easy to grow, and are beautiful as well," added Prof Ratnieks.
Tim Lovett from the British Beekeepers Association commented that the balance of urban and countryside beekeeping may have become skewed.
"With all that concrete and steel and tarmac you probably do approach the supportable maximum [population of bees] more readily than you might do in a non-urban situation," he said.
As a self-labelled "townie" his advice to bee enthusiasts in the city is to "consider the availability of forage, the presence of other hives nearby, getting adequate competence of beekeeping.. and above all: do it slowly."
"Learn to do it right and you'll get much more out of it."