The World Health Organization (WHO) reported that 9 out of 10 of the most polluted cities in the world are now in India. Not only does this make life a challenge for local people, but also for wildlife in those areas.
New studies show that air pollution threatens not only humans but many other organisms, including the key pollinator of food, the honeybee. Whether it is from the harmful particles in the air they breathe or due to contaminated water and food sources, pollution in the wild causes behavioral, neurological and reproductive deficits in animals.
A study recently published in the journal, Proceedings of the National Academy of Sciences, evaluated what sort of effect air pollution has on Apis dorsata, the giant Asian honeybee. This is the largest honeybee, at nearly one inch long, and lives throughout Southeast Asia where it plays a vital role to the floral and faunal diversity of the region.
This pollinator is an invaluable member of the surrounding ecosystem, responsible for approximately 80% of India’s honey as well as pollinating over 600 plant species. Without these bees, India would suffer a massive decline in the production of popular vegetable and fruit exports and could face serious food chain insecurity.
This 0:57-second video about air pollution's effect on bees is by UN Environment Programme:
A team of scientists from Bangalore Life Science Cluster studied the effects of global air pollution on nature, observing over 1,800 Asian honeybees during a four-year period to find some answers. They discovered a pattern of negative side effects associated with pollution. Consistent with previous research on the topic, they found that the giant Asian honeybee pollinated far fewer flowers in the highly polluted areas of Bangalore, due to air pollutants interfering with the scent molecules released by plants to attract bees. This caused the bees to be slower at finding food and pollinating.
Bees living in the more polluted areas had health issues like heart rhythm deficits, blood cell count, and less overall resilience to illness. This was not an isolated incident, since running the same tests of fruit flies led to similar outcomes.
Dr. Hema Somanathan, expert in bee behavior and pollination ecology at the Behavioral and Evolutionary Ecology (BEE) Laboratory, Indian Institute of Science Education and Research in Thiruvananthapuram, clarified that the study was performed on wild bees that naturally visit flowers in Bangalore city, and not in lab assays on reared honeybees kept in apiaries that may already be stressed or immuno-compromised. This study provides hard evidence that all is not well with the wild bees. And given the scale of landscape alteration and urbanization in India, these effects are likely to be widespread and to worsen as time goes by.
The study authors said they were shocked to find that 80% of the bees they collected died within 24 hours of acquiring them from more polluted areas, very similar to the predictions made by the WHO.
In response to the death rate of collected bees, Arunabha Ghosh, founder and CEO of the Council on Energy, Environment and Water, believes this study covers important new ground concerning the impact of air pollution on pollinators. This has serious implications for India’s agricultural output, and highlights the need to raise India’s ambient air quality standards.
As was found in many parts of the world, research shows that India’s notorious air pollution has significantly cleared following the massive Covid-19 pandemic lockdown. According to the Centre for Science and Environment, harmful air pollution in New Delhi dropped a staggering 60%. Trains, traffic, flights and factories shut down for a substantial period of time. Research is needed to see how this may have affected wildlife. Experts say the clear skies over India now make it clear that positive change is possible.
Shloka Nath, executive director of India Climate Collaborative and head of sustainability and special projects at Tata Trusts, believes the research speaks for itself. These studies and the observations of clearer air after the Covid-19 lockdown provide concrete proof that we are not just endangering ourselves but also the wild animals and plants.
While this post concerns India, these research findings apply to any city where air pollution disturbs wild bees and other pollinators, and damages complex ecosystems. Air pollution affects us all, our quality of life, food and habitat, for all of us depend on bees and pollination.