According to a study looking at trends in wild bees and hoverflies in Scotland, England and Wales from 1980 to 2013, a third of species have experienced a decline in their population. If this continues, some species could become extinct; this could have a major impact on our ability to grow food crops in the future, as the majority of pollination of food crops and plants is done by wild insects, rather than honey bees from hives.
The decline is likely caused by a number of factors, including habitat loss, climate change and the use of insecticide. In an attempt to combat this, the European Union introduced a temporary ban on the widespread use of insecticides. Recently, this ban has been made permanent for three of the main types of insecticides (neonicotinoids) and it now also covers all crops grown outdoors. While conservationists are hopeful that this will encourage a growth in the number of pollinators, scientists say that the restrictions have not been in place long enough to determine their effectiveness.
As mentioned before, this decline could have a very negative impact on food production in the UK. Dr Gary Powney of the Centre for Ecology and Hydrology (CEH) in Wallingford, Oxfordshire warned that although some species have not experienced a drop in numbers, “it would be risky to rely on this group to support the long-term food security for our country. If anything happens to them in the future, there will be fewer other species to step up and fulfil the essential role of crop pollination.” This means that if the current most common species of bees were to start declining in future (this could be due to a disease), there would not be enough bees to support crop pollination, whereas if different species of bee (currently in decline) were to become more numerous, they would be able to pollinate crops in a case such as this, and the damage wouldn’t be as severe. Therefore it is essential that the biodiversity of bees is kept in tact.
“Every square kilometre in the UK has lost an average of 11 species of bee and hoverfly, between 1980 and 2013, according to the new analysis,” said Dr Lynn Dicks of the University of East Anglia. The loss of insects not only affects food production, it also has an effect on entire ecosystems; since insects make up the food source for other animals (birds, amphibians, bats and reptiles), this could result in a drop in numbers for these creatures as well.
The species that are currently declining are rarer, specialised species, such as solitary bees living in burrows in the ground, and upland bees living on mountains and moorlands.
In order to encourage bee populations to increase, farmers and gardeners are advised to make an effort to be wildlife-friendly by allowing patches of wild plants and weeds to grow.