Invasion of the stink bugs: how a tiny insect roils global communities

A hazelnut-producing region of far-western Georgia is caught up in the global fight to save crops and livelihoods from devastating stink bugs.Monday, 20 May 2019

A stinky bug eating its way through the economy of an agricultural region in Eastern Europe stands as a stark example of how climate change creates opportunities for pests and havoc for farmers.

Abkhazia, a separatist region in far-western Georgia whose main agricultural export is hazelnuts, has seen its share of dark times, including war and ethnic cleansing. The latest crisis there comes in the form of the brown marmorated stink bug, an invasive species that also has set up residence in countries with more resources to fight them—the United States included. The bug has inflicted enough damage in Abkhazia to cause a near-state of emergency.

“We have approximately 15,000 hectares [37,000 acres] of hazelnuts in Abkhazia. As a result of the bug, more than 80 percent of our crops were damaged in 2018,” says Minister of Agriculture Amiran Kakalia.

Climate connection

Climate change is compounding the stink bug problem everywhere, says Erica Kistner-Thomas, a research fellow at the USDA Midwest Climate Hub. Longer warm seasons mean the bugs can reproduce more times each year, and regions that have become steadily warmer are now more hospitable to the invaders.

“We are already seeing major trends in Europe, the U.S., all across the world of insects emerging earlier in the spring after their overwintering periods, and sometimes entering overwintering at later periods,” says Kistner-Thomas. “And we’re expecting that to continue to happen in the future.”

This is ominous news for Abkhazia, which lies on the Black Sea, an area identified by the Georgian Ministry of Environment Protection as especially vulnerable to future climate extremes. And, because Abkhazia does not have university research labs or a culture of pesticide management, the proliferation of the stink bug could be much harder to control in a region where most farmers were ill equipped to respond effectively, according to Greg Krawczyk, an entomologist at Pennsylvania State University and an ambassador for BMSB control in Georgia, the world’s fifth-largest hazelnut producer and the country from which Abkhazia seeks independence.

Where did the bugs come from?

Originating from East Asia, Halyomorpha halys, sometimes known by the acronym BMSB, has spread across international borders via cargo containers and transported vehicles. The BMSB is thought to feed on nearly 200 host plants, and it has no known natural enemies outside of Asia, which has allowed it to multiply unimpeded and demolish major cash crops.

The stink bug has wreaked havoc across Europe and has recently become established in Chile. New Zealand and Australia have strict cargo offloading measures in place for the insects. In the U.S., the invader spread across 44 states in 20 years, and the Environmental Protection Agency has been using strong insecticides to combat the bugs.

Around the world, wealthy countries have managed to minimise populations of the bug and its economic impacts through such a highly orchestrated effort of pest control. But the bug’s recent arrival is still ravaging Abkhazia, where such resources don’t exist. While U.S.-allied Georgia received $3.5 million in stink bug aid in 2018 from the U.S., Abkhazia has received only 7 million rubles—roughly $109,000—from Russia, one of the few countries in the world that recognizes the contested republic.

Dreams dashed

Sveta Tabagua, a 66-year-old owner of a hazelnut farm, says, “This is the third year I’ve had no crops. I have no money left to pay my workers.”

It’s clear from her distress, the condition of her large, stately home, and the rambling hazelnut orchard that Tabagua has fallen on hard times.

“If the situation continues like this, maybe I will have to leave as the others. We moved back here thinking life would be better after the war, but now…” Her voice fades as she throws up her hands in a helpless gesture.

Tabagua’s feeling of desperation is echoed by other farmers in the Gali district of Abkhazia, where most hazelnut trees in the region are grown.

“We used to see the bug here and there,” says Murman Chaniya, a 40-year-old hazelnut farmer with 5,500 trees in the village of Otobaya-Hoshta. “But it was never a problem like it is now.”

Bug by bug

Abkhazia has adopted a homespun approach: In 2018 the government mobilized the public to collect stink bugs by hand and burn them, paying 1,000 rubles (about $16) per kilogram of bugs. The program continues this year and began as soon as the bugs emerged from their overwintering period.

But those efforts have not been enough. Many Abkhaz farmers are taking matters into their own hands, creating hand-made traps for the insects, devising light attractants, and building machines to spray pesticides.

“I’ve had to help myself. That’s why I invented this machine,” says Chaniya at his farm, one of the largest in the region. Chaniya uses a hand-welded metallic trailer with three sprinkler nozzles attached to spray pesticide through the spring and summer, an undertaking many other farmers cannot afford.

Chaniya is one of the luckier farmers. But still, his average harvest has been cut in half and sells for less.

“I know some farmers who have left the region and gone to Georgia,” he says. “With no harvests, there is no reason to remain here.”

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