"I don't want to raise any red flags unnecessarily," he said, "But growers are going to definitely need to remain vigilant starting in the 2013 season."
Bergh said the early arrival of spring last year also helped farmers and growers avoid the worst of the bugs; many early-season crops got a head start on the insects, which then emerged in smaller numbers.
"There was less opportunity for them to do damage," he said.
But Tracy Leskey, a research entomologist with the U.S. Agriculture Department, said the reduced population of bugs "essentially rebounded over the course of the growing season" last year, and homeowners saw far more bugs coming inside to overwinter than they did the year before.
"We have been trapping in the late season, and we know the populations are probably at least 60 percent greater this year compared to ," she said. "If they survive over the winter, there will be many more bugs in the spring."
At Butler's Orchard in Germantown, Md., co-owner Wade Butler said he and other employees discovered swarms of the insects recently while working in one of the farm's open barns.
"Between two boards or two pieces of wood, you'd see a couple of hundred stink bugs there," he said. "It was kind of surprising."
Still, he said, he was "cautiously optimistic" that the coming year might not be so terrible.
Fabbioli said he noticed a large number of second-generation, young bugs in the autumn, a shift from the previous year.
"We may be having some trouble [this year]," he said. "I hope they're wrong, but it definitely was more this fall — not as far as the damage to the fruit, but just visually, how many bugs you saw."