Skip to main content

Waterloo chemist putting a dent in next years gypsy moth infestation through sex and science

Waterloo -

A Waterloo chemist has come up with a way to help slow next year’s gypsy moth caterpillar outbreak.

Rosemary Chong has a PhD in chemistry, specializing in making insect pheromones, which is a sex attractant.

She is now using her skills to help put a dent in the gypsy moth’s reproductive cycle.

The invasive species are beginning to pupate and will soon become moths.

Once they do, male gypsy moths immediately begin their search to find female moths.

“The female secretes the sex attractant and the male flies upwind to the female, they find the females and they fertilize the female, and the female lays eggs,” Chong said.

Chong is hoping to intercept that exchange.

Rosemary Chong sorts lures she created to trap male gypsy moths. (Stephanie Villella/CTV Kitchener)

“So [male moths] don’t find the females, we’ll have a lot less eggs that get hatched next year,” she said.

She created lures, a rubber band soaked with an artificial version of the female gypsy moth pheromone.

The saturated rubber bands can then be used to make a homemade trap.

Chong recommends putting the rubber band in a plastic bottle filled with soap and water. The male moths will fly into the trap, and will eventually drown.

She said it’s best to set up the lure traps now before the caterpillars become moths.

“It’s not a magic bullet, it won’t get rid of everything,” Chong said. “All we are hoping for is that they will be reduced in numbers for next year.”

Chong has made more than 10,000 lures, she is now giving them away for free to anyone who wants them.

“If I can provide them so people can save their own precious trees, I’m all for that.”

The lures can be picked up at 345 Pommelgate Cres, Waterloo. The last day to pick up the lures is July 15, since after that day the moths will be mature and will have already mated.

For information on picking up lures, email

Chong is requesting if anyone wants to make a donation to donate to the local United Way or to the Canadian Wildlife Federation.


  • Trap caterpillars on trees under burlap and dispose of the insects
  • Use an insecticide to reduce numbers
  • Make sure trees are as healthy as possible by keeping them well watered so they can tolerate any defoliation from the caterpillars
  • Keep an eye out for egg masses later in the summer and remove them Top Stories

ICC war crimes tribunal hobbles on despite hacking

The Netherlands-based International Criminal Court was operating on Thursday with disruptions to email, streaming and document-sharing after a hacking incident earlier in the week, sources and lawyers at the tribunal said.

Stay Connected