Gypsy moth population increases in Wisconsin, according to new 2020 data

WISCONSIN (CBS 58) -- Wisconsin agriculture officials announced Tuesday, Dec. 15, the gypsy moth population has increased within the state. 

According to a news release from the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) caught 83,720 gypsy moths in 10,139 traps in the state this summer as part of the federal "Slow the Spread of Gypsy Moth Program." 

Below is a graph showing the number of moths trapped in the past four years: 

“Weather conditions were relatively mild across Wisconsin compared to the previous two years,” said Michael Falk, DATCP’s gypsy moth trapping coordinator. “Winter temperatures were not low enough to kill gypsy moth eggs, and spring conditions did not support the fungal and viral diseases known to kill gypsy moth caterpillars. As a result, gypsy moth populations rebounded after two consecutive years of population decrease.”

The DATCP says trapping gypsy moths is a tracking tool that measures the quantity and location of moth populations. Trapping data helps determine potential sites for next year’s aerial spray treatments. For 2020, DATCP treated about 145,625 acres in 18 counties.