Moths and other pollinators have trouble finding food amid vehicle exhaust

For years, regulators have tried to curb car and truck exhaust to promote healthier lungs and a cleaner environment. But new research suggests vehicle fumes do more than warm the planet and encourage asthma. They also mask the smells of crops and flowers, disorienting pollinators, like moths, in search of food.
Moths, butterflies, bees, and other pollinators are attracted to the floral sweet smells of all kids of flowers. But their olfactory sensors of moths are activated by all kinds of intense smells, say researchers from the University of Washington and University of Arizona. And background scents, like those from exhaust pipes of cars idling in rush hour traffic, make the flowers harder to find.
In lab studies, scientist were able to show how car exhaust influenced the way the Manduca sexta moth -- also called the tobacco hornworn moth -- detected flower scents, confusing them and leading them astray.
The lab studies, as well as field observations, were detailed in the latest issue of the journal Science.
"We'd assumed that the moth's ability to smell the flowers would be more specific," explained one the study's authors, Jeffrey Riffell, UW assistant professor of biology. "Instead, other volatiles also activated those same olfactory pathways."
The researchers would next like to study how other pollinators are affected by foreign smells.
"Beyond our work with moths, we'd also like to see if these volatiles affect other pollinators, like honeybees," Riffell said. "Such work could provide insight into whether urban emissions affect pollinators in farms neighboring urban centers."