HOW can anything a few millimetres long possibly be significant in the great scheme of things? We hardly notice these minute bugs and readily swipe and squash them without a second thought. After all, in a swarm of midges, there are hundreds if not thousands of individuals, so who is going to miss a few that are bothering us?

The problem is that, as mankind has found when he has introduced a non-native species such as the cane toad into Australia, nature should be balanced. "Big fleas have little fleas upon their backs to bit 'em. Little fleas have lesser fleas, and so ad infinitum" as the poet Anon penned.

We often talk about "top predators" and "head of the food chain". This brings to mind lions stalking prey in Africa or whales catching seals in the oceans. However, it also applies to small things. Wasps, for instance, collect sweet things such as nectar from flowers or jam from your sandwich picnic, but they also need meat to feed their developing larvae. That is why they are an extremely effective organic control for aphids in the garden. It is not only aphids. Wasps will also catch larger prey including flies and honey bees.

The balance in nature applies from the largest sperm whale to the smallest microbe. Somewhere along the line come the bugs, that enormous group of invertebrates.

Certain insects are well known, even if not everyone gets it right. I can't count the times someone has come up to an observation hive and said "Oh, look at the wasps!" However, that gives another opportunity to explain that, in fact, they are honey bees which live in a continuing colony rather than wasps which have an annual life cycle. The difference between honey bees and bumblebees can be described and people assured that bumblebees nesting under their garden shed or in the compost heap won't swarm and attack the baby but will, in fact, die out in autumn.

It is very gratifying that the majority of enquirers decide to leave the nest alone. Why is this important? Because with changing land use, suitable nesting sites and forage for bumblebees are declining. If humans were faced with the same problem, the result would be exactly the same. Numbers would decline. Many have already noticed fewer queen bumblebees noisily buzzing around in spring looking for nest sites. Most do not try to identify different species of bumblebee. Granted, some of them look almost identical and only a specialist can distinguish between them, but different they are. Surveys by Buglife, the Bumblebee Conservation Trust and others have shown that some of the seventeen bumblebee and six cuckoo bumblebee species found in Britain and Ireland are extremely scarce. Indeed, five are now included on the UK Biodiversity Action Plan List of Priority Species and two more are scheduled for inclusion. Three species have already become nationally extinct.

Why does it matter? What if the brown-banded carder bee (Bombus humilis), the red-shanked bumblebee (Bombus ruderarius), the distinguished jumper (Sitticus distinguendus) spider or the hump-backed red ant (Myrmica bessarabica) disappear? Who is going to notice? Who is going to care? What different will it make to my life?

In personal, everyday terms, the answer must be "not a lot". However, we are becoming increasingly aware of our natural environment and learning the importance of conservation and biodiversity.

Did you realise that 65 per cent of all species on the planet are invertebrates? In the UK alone, there are 32,000 terrestrial and freshwater species and 7,000 marine ones. Again, does it matter if a few become extinct? Yes, it does. These invertebrates have critically important roles in the balance of nature. If one is lost, like the dodo and the passenger pigeon it can never be replaced.

Two particular campaigns supporting bugs are worth mentioning here. One is for a rich diversity of very rare wildlife and the other is more specifically for honey bees.

Man has collected honey from bees for a very long time. He robbed wild nests until he developed methods for keeping bees in hives where they can be managed more easily. However, a beekeeper not only has to look after his bees, make sure they have sufficient space, try to stop them swarming and ensure they have enough food for winter, but he also has to take care of their health.

Bees are subject to diseases which affect both adults and brood and can weaken or even kill the colony. Until the varroa mite (Varroa destructor) arrived, again because of man's habit of moving species into unsuitable foreign situations, most diseases were well known and could be controlled. Treatments developed for varroa to keep mite levels down became ineffective when the mites became resistant. Beekeepers now have to employ different management techniques to keep honey bees alive. Wild colonies cannot survive on their own. Again the balance of nature is in jeopardy.

Things don't stop there. New pests and diseases await in the wings. The microsporidian, Nosema ceranae, infects the bee's gut, impairs pollen digestion and shortens the bee's life. Severe cases weaken or kill the colony. The western honey bee has lived with Nosema apis for a very long time and some colonies are apparently little affected. However, the Asian version, ceranae, is more virulent and affects colonies more quickly with greater colony mortality. Small hive beetle, Aethina tumida, is native to South Africa where the local bee can effectively keep it under control. Now it has arrived in the USA and is causing extreme problems as local bees there are unable to deal with it.

Colony Collapse Disorder (CCD) is devastating the honey bee population in the USA. Beekeepers are finding most of the bees have disappeared from their hives, leaving behind the queen and a small group of workers. A large research programme has received significant funding but no answer has yet been found. In fact, the more research done, the more complex the problem appears.

Nosema ceranae has been found in the UK. Small hive beetle is expected to arrive at some stage. The National Bee Unit has already drawn up a contingency plan to deal with this eventuality. CCD does not appear to be in the UK yet although some beekeepers are reporting significant colony losses. Beekeepers are very concerned. They want to get ahead of the game. This means research into bee health and research requires money. In the House of Lords on November 27, Lord Rooker, Minister for Sustainable Food and Farming and Animal Health, stated that the honey bee is at risk and if nothing is done, it could be wiped out in ten years. He also stated that these insects contribute around £165 million in extra agricultural yield through pollination.

These are strong words with which beekeepers agree, but soon afterwards Lord Rooker was telling the BBKA there was no money available on top of the £200,000 already allocated. BBKA has launched a campaign asking for an £8 million investment in bee health research over the next five years. Everyone is asked to support its petition (www.britishbee.org.uk).

This campaign is for one particular insect but down on the West Thurrock Marshes, strenuous efforts are being made by Buglife, the Invertebrate Conservation Trust, to protect an area rich in wildflowers and wildlife. Described as the third most important wildlife site in the UK, the marshes are home to more than 1,300 species of invertebrates, birds and plants. There are more rare and endangered animals there than on many of our finest nature reserves. Yet, this site has been chosen by Royal Mail for a new distribution warehouse and car parks covering an area equivalent to 15 football pitches. The project could have been built elsewhere, but Thurrock is what is known as a "brownfield" site and therefore considered ripe for development. Buglife took its challenge to the High Court in February but the judge ruled that the development was more important than the incredible wildlife. Buglife considers that loss of the site will result in extinction for at least two species.

On April 15, Royal Mail launched an attractive set of stamps featuring endangered invertebrates. With impeccable timing, on the same day Buglife announced it would continue to challenge the proposed development. They are asking for help to "Stop them stamping out our wildlife". Almost unbelievably, Royal Mail says "as our businesses grow, it's our responsibility to take into account the environmental effects of what we do and by minimising our impact on the environment we can help create a world in which our company can continue to flourish". Please support Buglife's campaign. You can donate to the charity at www.buglife.org.uk. Letters to Royal Mail's chief executive, Adam Crozier, should be sent to Royal Mail Group, 148 Old Street, London EC1V 9HQ.

Invertebrates have an essential role in the food supply chain. Insects are vital for pollination of many species. Without pollination, lots of our food crops simply won't set seed and food will become scarce. We are already seeing the price of vegetables and other foodstuffs rising because of short supply.

Bugs are essential for wildflowers. Without fertile seeds, these will not propagate from year to year. There is a vicious circle. Without pollination, wild flowers decline. With fewer flowers, the nectar supply is reduced with reduced food supplies for invertebrates. Fewer invertebrates means less efficient pollination, and so on. But it is not only this circle. Other circles of life overlap. Bugs are essential food for many birds and mammals. Blue tits time their nesting so that chicks hatch when there is an abundance of green caterpillars on which they can feed. Fewer bugs equals fewer birds and mammals. Birds and bats are also essential pollinators, compounding the problem.

Birds eat bugs for their survival but this can also benefit man. By eating some of the creepy crawlies, such as aphids, they rid man of pests. Medical research has also identified useful substances originating from bugs, again for the benefit of mankind.

Sir David Attenborough summarises the situation. "If we and the rest of the back-boned animals were to disappear overnight, the rest of the world would go on pretty well. But if the invertebrates were to disappear, the world's ecosystems would collapse."

Think about that next time you see a queen bumblebee searching for a nest or jump when a spider runs across the carpet. Bugs are not only important, they are an essential part of the ecosystem of our world. We need to take care of our environment, down to the last fruit fly. n