Brain Food: Where Do Japanese Beetles Come From?
Voracious Japanese beetles are becoming frequent fliers on airlines traveling from the East Coast to the West Coast. And that’s wreaking havoc on hundreds of species of plants. Ecosystem scientist Bruce Hungate is trying to find out how the beetles are getting their boarding passes.
“When you see a Japanese beetle in an area where they haven’t been before, you might wonder, ‘Is this a sign of an establish, or worry about the same way?’” he says.
In his lab at Northern Arizona University, Hungate studies the chemical composition of Japanese Beetles to determine where they came from and how long they’ve been in their new location. He grinds up dried beetles in a machine called an elemental analyzer looking for location specific hydrogen isotopes.
“In order to know how to manage an invasion, you need to know what the status of the invasion is,” Hungate says. “You need to know if it’s the source populations that are the biggest problem. Or you need to know if you’ve got an established new population in a new location, and that’s really where the hydrogen isotopes help. Because when you look at a beetle, you can’t ask it, they can’t talk, ‘When did you get here? Do you have any brothers and sisters who are living here with you?’ Right?”
Through this process, Hungate has been able to determine how long the Japanese beetles have been at their latest destination as their hydrogen isotopes begin to reflect their new environment. He believes this method will help pest control efforts aimed at protecting plants from the destructive insects.