The Middletown Press (Middletown, CT)
Citizen scientists track invasive species
LITCHFIELD — Seven people scurried around the baseball field under the midday sun, swooping neon butterfly nets to catch wasps hovering above their nests on the diamond.
A wasp easily flew out of the net leaving behind the beetle she was carrying. This time, the bug was emerald with a bright green belly, a telltale sign it was the dreaded emerald ash borer — an invasive insect that arrived in Prospect in 2012 and has been ravaging the state’s ash trees since.
“It’s worth trying to slow down,” said Claire Rutledge, an entomologist with the Connecticut Agricultural Experiment Station leading the Wasp Watchers program.
Under Wasp Watchers, citizen scientists, entomologists and environmentalists track colonies of cerceris fumipennis, which is commonly known as the smokey winged beetle bandit. This native wasp eats beetles in the same family as the emerald ash borer and so collect it along with the native prey. Researches use the wasps to collect the samples of these insects, gathering them from the wasp on her way back to the nest or picking dropped ones off the ground.
Rutledge said the wasps are great because they are able to get the insects from the tops of trees, where humans are unable to get the beetles, providing a true sense of how prevalent the emerald ash borer is. Also, the wasp only stings the beetles, not humans.
By surveying the insects collected at specific sites, Rutledge and her team at the experiment station can determine where that locality is in the infestation cycle. Based on the amount observed last week, Rutledge suspects there will be another two years before it hits peak and the ash trees die out, leading to the population crash then of the emerald ash borer.
This month, emerald ash borer was collected for the first time in Ridgefield, North Stonington, New Canaan and Salisbury. Rutledge said she wasn’t surprised to see the pest in Ridgefield because all of the surrounding towns had sitings and it was already believed to be there.
“North Stonington was a surprising one, Ridgefield was more of filling in the holes,” Rutledge said. “North Stonington is the furthest east it’s been so Rhode Island better look out.”
The emerald ash borers have traveled from the center of the state out toward the corners of the state in a patchwork style. They spread largely due to human activity, such as transporting fire wood, which is why firewood isn’t allowed over state lines. The insects themselves only travel a mile a year.
There are 80 to 100 colonies monitored across the state, including several in the Danbury area. Though they are called colonies, Rutledge said they’re really more aggregates of single wasps who work independently.
Rutledge has about 20 to 30 returning watchers and held a few trainings this month and last to add another 20 or so to the ranks.
Rutledge began the Wasp Watcher program in 2008, a few years after the idea started in Canada.
James Fischer, research director at the White Memorial Conservation Center in Litchfield, became involved in 2012 after hearing emerald ash borers were colonizing in Connecticut. The organization oversees 4,000 acres of forest, about 6 to 7 percent of which are ash trees, and needed to prepare for the inevitable emerald ash borer invasion.
“We knew it was coming, but we didn’t know when,” Fischer said.
This allowed them to plan for how to manage the forest and which trees to remove once the insect was discovered in 2014. He said the emerald ash borers are so overwhelming that they can really only document and plan so they can afford the tree removal in the aftermath.
“The best we can ask is to slow it down and be as proactive as possible,” he said. “Prevention is something not in our means right now.”
Rutledge said that’s generally the case across the state. Most towns and electric companies have to remove the ash trees, which is costly and why it’s such an expensive pest. Knowing the point of the infestation is crucial in determining a management approach.
“It’s always better to know where the problems are,” she said.
The project has other benefits too.
Through the group’s efforts, the experiment station has a better idea of not only what the the emerald ash borer numbers are, but the overall state’s beetle population, which tend to be under collected because they live in treetops.
“With this project, we’ve been getting 26 new state records in finding beetles we didn’t know were here,” she said.
Rutledge said the project is also a great outreach tool, which gets people more invested in invasive insects.
“They’re such charismatic guys and it’s so much fun to do that it’s been a really successful citizen science program,” she said.
Linda Rumsey-Dolega, of Trumbull, is one of the newest volunteers. She’s a master gardener intern and wanted to be a trained wasp watcher as well because she thought it sounded fun and different.
“It’s a positive use of your time,” she said.