A new study lead by the National Centre for Biological Sciences (NCBS) researchers have revealed how air pollution may be depleting the health of honey bees in the wild.
Apis dorsata or the Giant Asian Honey Bee produces over 80 per cent of the country's honey and pollinates over 687 plants in Karnataka alone. An important pollinator, without the honey bees, India's yearly mango export would lose over ₹65,000 Lacs.
The four-year study of over 1800 wild bees was led by Prof Shannon Olsson and published this week in the Proceedings of the National Academy of Sciences, USA.
For the study, Geetha G Thimmegowda, a Postdoctoral scholar in Olsson's lab at the institute, collected honey bees in and around Bengaluru. Geetha found that while a bee collected from the BLiSC campus on the northern and relatively low-polluted edge of the city carried a large amount of pollen on her body, a bee from Peenya, an industrial area, was covered in small particles containing lead, tungsten, arsenic, and a host of other toxic metals.
The researchers found that over 80 per cent of the bees that were collected from areas that are moderately or highly polluted died within 24 hours.
"I couldn't believe what I was seeing. I remember turning to Geetha with tears in my eyes and saying - We have to work on this and find out what this pollution is doing to our wild animals. People need to hear about this, and more importantly, people have to care," said Olsson.
"There are extreme gaps in our knowledge on the status of our wild pollinators in India. This study by Dr Olsson and colleagues is a very important step in addressing this pressing concern. Bees are important pollinators in our landscapes, and this study clearly shows how pollution adversely affects the health of bees," said Dr Hema Somanathan, who studies bee behaviour and pollination ecology at the Behavioural and Evolutionary Ecology (BEE) Laboratory, Indian Institute of Science Education and Research, Thiruvananthapuram.
"The study was done with wild bees naturally visiting flowers in Bangalore city and not in lab assays on reared honey bees kept in hive boxes that may already be stressed or immuno-compromised. Thus, in my opinion, this study provides us with hard evidence that all is not well with our wild bees. Given the scale of landscape alteration and urbanisation in India, it is expected that these effects are widespread and likely to worsen with time," she added.