As Britain's natural environment is being gradually degraded, with the demise of traditional hedgerows, hay meadows, chalk grassland and wildflowers, the intensification of farming and the widening use of pesticides, our bumblebee population is steadily vanishing.
Already three of the 25 species traditionally found in the UK have become extinct, and conservationists fear several more are in imminent danger if action is not taken quickly.
Today The Independent is backing the launch of the Bumblebee Conservation Trust, a pressure group designed to protect and save bumblebees - and inviting Independent readers to join.
Set up by the UK's leading bumblebee expert, Professor Dave Goulson of the University of Stirling, the trust aims to raise awareness of the problems bumblebees face, and help prevent further decline. Its website proclaims it has been founded in response to growing concerns about the "plight of the bumblebee".
The membership, which ranges from internationally renowned research scientists to enthusiastic and concerned amateurs, is open to everyone. And everyone can make a difference, for the trust is inviting members not just to watch out for bumblebees, but to plant their gardens with flowers that will help reverse their population declines.
"With luck, the BCT can be a force for positive change, helping to boost biodiversity in gardens and in the farmed countryside," said Professor Goulson, of Stirling's School of Biological and Environmental Sciences.
"Bumblebees are key players in ecosystems, and seem to be very sensitive to environmental change, so if we can get things right for bumblebees, then lots of other wildlife will benefit too. If we do not act soon, more bumblebee species could be lost."
Between them, Britain and Ireland have had 25 native species of bumblebee, out of which three have already become extinct - the apple bumblebee, Cullum's bumblebee and (recently) the short-haired bumblebee. Four more are designated "UK Biodiversity Action Plan [UKBAP] species" in recognition of their precarious situation - the great yellow bumblebee, the brown-banded carder bee, the shrill carder bee and the ruderal bumblebee. Several more species, such as the bilberry bumblebee and the moss carder bee, have had major range contractions.
"We believe that bumblebees are fascinating and beautiful organisms that deserve conserving in their own right," said Professor Gouslon, stressing the importance of the insects for the natural environment and agriculture. Bumblebees are major pollinators of flora, and if they continue to disappear many traditional native plants will suffer, reproduce less, and cause a ripple effect of sweeping changes to the countryside.
Some types of clovers, vetches and many rare plants have already started to disappear from traditional areas.
Ultimately, the BCT warns, the landscape could become dominated by an entirely different suite of plants that do not require bumblebee pollination. Such a change to the balance of nature could be catastrophic for wildlife dependent on these plants. "Bumblebees are keystone species," said Professor Goulson. "They are a conservation priority."
In addition to the adverse effect on the environment, the demise of the bumblebee could have a serious impact on trade. Many crops depend on bumblebees for pollination and some, such as broad, field and runner beans and raspberries, are heavily dependent on them. Without the insects there would be little or no crop to harvest.
The BCT believes existing nature reserves cannot conserve the remaining populations alone - there just are not enough of them. Each bumblebee nest can contain up to 400 sterile workers, each of which travels more than a kilometre from the colony in search of suitable flowers. As a result, an area of many hectares of flower-rich habitat is needed to support a healthy, sustainable population.
"UK nature reserves are simply too small," Professor Goulson said. "The only way to provide sufficient areas of habitat for bumblebees is if the wider, farmed countryside, and the vast areas covered by suburban gardens, are managed in a suitable way. To do this we need to educate people, and encourage activities such as the planting of wildflowers and traditional cottage-garden flowers in gardens, the replanting of hedgerows, and the recreation of hay meadow and chalk grassland habitats.
The trust says most gardens in the UK should be able to attract at least six bumblebee species if they are stocked with the right plants. New members are sent wildflower seeds when they join.
How you can help
To help combat the problem of the country's declining bumblebee population, the Bumblebee Conservation Trust wants gardeners to use more traditional native plants. These include bluebells, rosemary, geraniums and honeysuckle, which bumblebees prefer to the more exotic imports.
The trust says most gardens in the UK should be able to attract at least six bumblebee species if stocked with the right plants. A packet of suitable wildflower seeds is one of the first things new members of the trust receive, along with a bumblebee identification chart and a newsletter.
Independent readers can join by accessing www.bumblebeeconservationtrust.co.uk, and downloading a membership form.
Membership costs £16 a year, which can be paid by cheque, made payable to the "Bumblebee Conservation Trust", and sent to Bumblebee Conservation Trust, School of Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA.
" The Independent is very strong on environmental issues, and readers can make a real difference to the fate of the bumblebee, which is one of our key creatures," said Professor Dave Goulson, of Stirling's School of Biological and Environmental Sciences.
Five bees you might spot in the garden - and five that may prove more elusive
Short-haired bumblebee BOMBUS SUBTERRANEUS
Recently extinct. Last seen in 1988 at Dungeness nature reserve on the south Kent coast. A short-haired, baldish bee which lived in the south because of the temperate climate.
Probably died out due to the decline of red clover. New Zealand has a 100-year-old "expat" community.
Great yellow bumblebee BOMBUS DISTINGUENDUS
Britain's rarest surviving bee.
Used to be found as far south as Cornwall - now only in the Hebrides, Orkneys and a few of the northern-most clifftops of mainland Scotland. The most likely to go extinct in the near future because of the destruction of flower-rich habitat.
Ruderal bumblebee BOMBUS RUDERATUS
Used to be common all over England; its old name was the large garden bumblebee. But you would be incredibly lucky to find it in your garden nowadays.
Spotted only in a few sites in the Midlands and East Anglia, in or around the edges of marshes. Another species to have suffered from the dramatic decline in red clover, its staple food.
Shrill carder bumblebee BOMBUS SYLVARUM
Also rare. So called because it is smaller and makes a higher-pitched noise in flight. A southerly species found on Salisbury Plain, and interestingly at some brownfield sites near the Thames Estuary, buzzing between the burnt-out cars.
Not brightly coloured, with fuzzy stripes.
Brown-banded carder bee BOMBUS HUMILIS
Now found almost exclusively around coasts, it likes dry, chalky cliffs and downlands. The best place to find it is Salisbury Plain; where it survives only because the Army presence prevents the area being taken over by intensive farming.
White-tailed bumblebee BOMBUS LUCORUM
A common garden bee with a short tongue, so feeds on shallow flowers and is not a particularly fussy eater, happy to dine on many of the more exotic garden flowers at which the rarer bees turn up their noses - hence its healthy number. Often nests under the floors of wooden garden sheds. Found more or less everywhere in Britain.
Red-tailed bumblebee BOMBUS LAPIDARIUS
All black with a red tail, it is the most distinctive of Britain's bees. It adores white clovers but is also an important pollinator of oil-seed rape.
Incredibly abundant on chalk downland in the summer. Also common in arable fields with oil-seed rape and turns up in gardens.
Garden bumblebee BOMBUS HORTORUM
The only long-tongued common bee, it feeds on different nectars to the others: the absolute favourites are red clover and foxglove, one of the deepest flowers.
Tends to have smaller nests with perhaps 30 or 40 workers, compared to 300 to 400 in buff-tailed or white-tailed nests. Strangely, given its name, it is the least abundant of the common bees to be found in gardens.
Early bumblebee BOMBUS PRATORUM
As the name suggests, it is the first of the bumblebees to appear each year, coming out of hibernation in the early spring. Can be easily spotted in April.
Its very short lifecycle means it begins hibernation again in June. Seems to be one of the few bumblebees in Britain which nests in tit boxes up trees, rather than on the ground.
Common carder bee BOMBUS PASCUORUM
Few people would recognise it as a bumblebee owing to its brown colour. Important for gardeners as it is the only bee to pollinate broad beans.
So called because "carder" comes from the world of spinning wool - these bees use their legs to comb moss to make a nest. Found in gardens across the country.