Where did all the bees go?
Honey bees have been dying off in the past decade at an alarming rate. Similar trends are also visible across other species of wasp, butterfly, and beetle.
Scientists have been extremely concerned about the decline in pollinators that includes the semi-domestic honey bee. Bee keepers and ordinary gardeners continuously report the lack of bees in their gardens. Species that were seen 2 years ago, are now nowhere to be found. A slow decline in the honey bee population became evident until, after only one year, there were none left, begging the question, “where have the honey bees gone?”
Bees have had to contend with a number of stressors including climate change and habitat loss, as well as a number of human-introduced chemicals. In the end, the combined result of all of these stressors have already taken a toll on the survival of these insects that are critical to the survival of our species.
Naturally, suspicions fell on insecticides used to protect crops from insects by mega-dollar industries. With huge losses at stake outcries to stop the use of insecticides fell on deaf ears as they were not feasible and seen to be unreasonable by chemical companies. There is reasonable concern regarding the undue influence that multi-national chemical companies can have in the granting of licenses and the continued supply of their products despite widespread outcries from the public.
However, if we are going to save our environment we need to know exactly what has happened to the bees and something needs to be done about it as soon as possible. Concerned with the increasing mortality rate of bee colonies the Committee of Brighton and Lewes Beekeepers supported a decision to investigate the effect of insecticides on honey bees.
Fingers were pointed to neonicotinoids, chemicals that are applied as a coating for crop seeds. The concern was that, although bees don’t frequent seeds, small quantities of sprayed chemicals settle on nearby flowers that bees and other insects visit and persist for months.
In the process of pollination bees and other insects visit hundreds of flowers that may expose them to tiny amounts of pesticides many times over. These harmful chemicals are carried to other flowers and from there to insect nests and bee hives where small amounts of toxins are deposited and accumulate.
According to the Committee of Brighton and Lewes Beekeepers many scientific papers exist that implicate chemicals, specifically neonicotinoids such as Clothianidin, Imidacloprid, Fipronil (a carcinogenic phenylpyrazole) in the death of our bees.
There is also increasing evidence that the immune systems of bees are impaired by these insecticides which weakens them and renders them more susceptible to parasites and diseases such as Nosema. The probable synergistic action between insecticides and other chemicals may also be lethal to bees and needs further investigation.
A recent large scale study from a European team of researchers compared the effects of neonicotinoid with control over two years. The study found a complicated set of results that were different for the different countries involved in the study.
In some countries there were clear losses of bees while in others no significant differences were found between conditions. In the UK such a large amount of bees died under all conditions that no statistical comparison of the effects could be made. Overall results show a definite loss of bees and that in some cases insecticides may have contributed to these losses. It is most likely that neonicotinoids weaken the immune systems of bees that make them more vulnerable to external challenges and diseases.