Study: neonicotinoids can impact bees’ social behaviors

For a many years, scientists and individuals alike, have become more and more concerned for the world’s bee population. Now a new study conducted by Harvard University biologist, James Crall, concludes the effect of neonicotinoid insecticide or “neonics” for short, causes bees to provide substandard care to their young.

In this study Crall observed the effects of Imidacloprid, a chemical similar to nicotine which belongs to the neonic class, on 12 colonies of Bombus impatiens, a species of bumblebee.

Crall discovered very unusual behavior by the bumblebees, especially at night. Bees who were exposed to Imidacloprid rarely nurtured or fed their larvae and spent most of their time on the outer edges of the nest.  Other findings showed bumblebees usually build a canopy- like structure made from wax, to regulate their young’s body temperature. However, findings show the exposed bees are less likely to build these canopies. Thus, reducing the survival rate of the larvae and overtime the population of bumblebees.

Although this study was conducted on bumblebees, Dr Andrew Barron of Macquarie University says it is not “unreasonable” to assume there are effects on other bee species too.

The effects of insecticides can vary, depending on species and location. Scientists believe these chemicals will have the greatest impact on native bees, as they only forge an estimated 300m from their nest and cannot dilute chemicals if consumed, as opposed to honey bees, who forge a much further distance and could have exposure to both treated and untreated plants and will therefore be able to dilute the insecticide.

Studies by Europe and the US show their population of native bees has declined by fifty percent. The European Union has banned the use of neonicotinoid insecticides because of their effects on pollinators.

 Although this has been the case for some, other countries such as, Australia, have not had a decline in their bee species and as such have no intention to review the laws behind insecticides. However, certain Australian retailers have made a voluntary decision to not stock their shelves with neonicotinoid for home use.

Australian Pesticides and Veterinary Medicines Authority website states neonics-based products are “safe when used according to the label directions”.