Spotted lanternfly sightings are up 500% in PA compared to last year

Summertime brings the “nymph” phase of the invasive insect, a prelude to mature bugs this fall.

Billy Penn illustration
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If you’ve spent time outside this summer — which you probably have, since it’s one of the only safe things to do during the pandemic — you’ve almost definitely seen them.

The spotted creepy crawlies with vibrant red coloring or high-contrast black and white dots and spindly, spider-like legs are everywhere right now. They’re spotted lanternfly nymphs, and, yes, they jump around like popcorn, complicating efforts to squash or brush them away.

There might also be more of them than ever before.

The Pennsylvania Department of Agriculture has logged almost six times as many reports of spotted lanternflies this year compared to last, spokesperson Shannon Powers told Billy Penn.

From the start of January to the middle of July, Pa. residents had called in 33,015 sightings of the invasive buggers, compared to 5,603 over the same time period in 2019, an increase of nearly 500%. Philadelphia accounts for the largest share of reports with more than 7,800, followed by nearby Delaware and Montgomery counties. Powers said 80% to 90% of Philly reports have been substantiated.

It’s not yet clear whether the sharp uptick is evidence of a more severe season — or the result of higher awareness and more outdoor leisure time.

“It’s a tremendous challenge to figure out whether it’s an increase in population or just an increase in awareness of the insect,” Powers said. “We know for a fact that awareness has increased.”

The department probably won’t know whether spotted lanternflies are more severe until next year, because researchers rely on data collected in prime adult season, which doesn’t happen until fall.

Regardless, it certainly feels like the harmful-to-plantflife species is taking over the Philly region for yet another summer. Last year’s invasion sparked literal horror movies, creative bug-killing methods and even jewelry made from the colorful arthropod bodies.

“Once the insects hit urban areas like Philly last year, the media had fun with it and people became aware of them,” said Powers.

Summertime adolescence

Before they turn into the fully mature winged tree terrorists people got good at stomping on last year, spotted lanternflies go through several life cycles.

Those pervading the region right now are in the insect’s fourth instar phase, according to Jon Gelhouse, entomology curator at Drexel’s Academy of Natural Sciences, which held a recent Facebook Live discussion on the critters.

Fourth instar nymphs are bright red with white spots and black lines, and they’re the lanternflies’ last phase before adulthood.

If you’re unfortunate or interested enough to look closely, you could see some wings developing. The insects will likely reach final form in the next couple of weeks, according to Karen Verderame, invertebrate keeper at the Academy.

When did the invasion start?

The first official Pennsylvania spotted lanternfly sightings were in Berks County in 2014. The creatures likely arrived as eggs on shipments of rocks and cement from Asia, according to Verderame at the Academy of Natural Sciences.

It didn’t take long for the little creatures to cause a big problem.

Spotted lanternflies eat the sap of more than five dozen different kinds of trees and flora, and their poop attracts a mold that eventually kills plants. They’re particularly attracted to the Tree of Heaven, a weed native to China called that has proliferated all over Philly, but will take over nearly kind of plantlife they find.

The insects have now colonized several mid-Atlantic states, including New Jersey, Maryland, Delaware, Virginia and West Virginia.

How do we stop them?

This winter and early spring, insect experts instructed people to hunt and destroy spotted lanternfly egg cases. Clearly, more than a few slipped through the cracks.

Spotted lanternflies cross county and state lines by traveling on vehicles, materials and people. Southeast Pa. is especially vulnerable, because it’s so accessible, Powers said.

To help stop the spread, the Pa. Department of Agriculture in 2015 enacted what they called a quarantine (triggering, we know). The measure puts restrictions on certain vehicle travel and transportation of wood, rocks and plants. Philly has been on the list of quarantined counties since 2017.

lanternfly-quarantinemap-pa

Map of Pennsylvania's lanternfly quarantine zones

Pa. Dept. of Agriculture

Methods used to fight the invasion include removing trees that have been infected and installing nets around nearby remaining trees. (An earlier model of the trap relied on sticky paper, but was inadvertently catching other insects, birds and small mammals.) These traps are set up in various high-traffic areas like rail yards, bus stations and state parks.

Powers said the Port of Philadelphia has been an important partner because treating shipments from overseas has been crucial in controlling national lanternfly spread.

The Department of Agriculture is calling on people in quarantined areas to inspect themselves and their vehicles before moving around, since spotted lanterflies are hitchhikers.

Residents with backyard infestations can purchase or make their own tree traps, remove plants that attract the insects, and use insecticides. You also can report spotted lanternfly sightings online or by calling 1-888-4BADFLY (1-888-422-3359).

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