The war on foreign-invader bugs

Steve Switzer is like a kid with toy. He closes his lips over a straw-sized tube, sucks in, and poof! A tiny insect on the table vanishes from sight, then reappears inside a small plastic vial.

"That's how you catch a bug, hands-free," he says with obvious delight, like he had just performed a magic trick. "You don't squish it, you don't damage it."

Switzer is an agricultural specialist with U.S. Customs and Border Protection in Charleston under the Department of Homeland Security. It's his job, along with a dozen other people in his office, to hunt down the bad bugs of the world and stop them from entering the United States. No, it's not the same as thwarting terrorists. But both are forces of destruction, only with different targets.

The interception of insects is serious business, and it takes place daily in Charleston, mostly because of the ships from across the globe that call on the port. Flying and crawling creatures are but one category of pests that Border Protection is on the lookout for, along with plant and animal diseases, weed seeds and snails. They check out shipping containers, inspect military aircraft, airport baggage, cruise ships and other pathways for the unwanted travelers.

The objectives are both economical and environmental: The yearly impact

of invasive species and weeds in the U.S., including control and prevention, is $134 billion. Both can destroy foodstuffs, crops, forests and animal habitats.

Most of the bad foreign bugs never become household names, but a few are infamous: the Japanese beetle, which arrived in 1916, or the imported fire ant, in 1919.

Working together

In a large, nondescript warehouse off Clements Ferry Road and a quiet office suite in North Charleston, two federal agencies join forces to collect and identify bugs or larvae that may have burrowed into wood or a bag of rice or hitchhiked on a piece of Italian tile.

Border Protection specialists are like arresting officers, but all of them have science backgrounds. They seek and capture insects in the field, both dead and alive. The suspect bugs (most having been dropped in a vial of alcohol) then go to the Animal Plant Health Inspection Service, which is under the U.S. Department of Agriculture.

There, entomologist John Weaver puts the bugs under a microscope to determine exactly what they are and whether they pose a risk. He identifies insects that come from the Charleston and Savannah ports, sometimes with the help of the Smithsonian.

"Our big thing right now is the Khapra beetle," which is coming mainly from Mideast and African countries, Switzer said. "It is considered to be one of the top 10 serious pests in the world."

Switzer said the Khapra beetle is the only pest in the world that the government would take action on even if only the cast, or skin, was found. Otherwise, a live specimen is required.

The tiny brown beetle can do great damage quickly. It likes to hide in rice, lentils and Indian and Pakistani foodstuffs and spices. If the Khapra beetle gets established in a stored grain, it feeds and multiplies so rapidly that the grain is soon ruined.

Because facilitating trade is a big part of the USDA's mission, Weaver said, the focus on the beetle is well-deserved.

"The United States is one of the few countries in the world that does not have Khapra beetle. That's a real plus for exportation of our agricultural products."

Close inspection

Only a certain percentage -- the government won't say exactly -- of shipping containers get opened up and personally inspected. But the process isn't random. Agriculture specialists screen documents, looking for red flags before a ship ever sails from a port.

Those include countries or regions that are insect hot spots and importers or shippers with a history of customs violations. Intelligence information can come into play. "We're very risk-based," Switzer said.

A container tagged for inspection is taken from the port to the Clements Ferry warehouse. At the loading dock, Customs specialists start sleuthing for insects, both outside and inside the container. Once the door is opened, any flying insect would be an immediate target.

But specialists also carefully examine the cargo. They will open boxes or bags of rice or corn to extract samples. They may vacuum dirt from the floor for a closer inspection as well. They look for telltale signs of bug-feeding, like sawdust.

The old needle-in-a-haystack analogy applies here, with some bugs no bigger than a flea or a gnat, like the Khapra beetle. "You have to have good eyesight," Switzer said. "We don't get a gun but we get a very nice flashlight."

Most of their tools are relatively low-tech. Officers use giant butterfly nets, tweezers, pocket knives, pry bars and chisels. The most useful, said Switzer, is the aforementioned "bug sucker," a $7 device officially called an "aspirator." In any case, the idea is not to damage the insect to impede identification.

Wooden packing materials such as crates, pallets and bracing are notorious hideouts for wood-boring insects. "It's a big pathway for the introduction of invasive species," Switzer said. Such pests include the Asian long-horned beetle, considered one of the most destructive non-native insects in the United States.

The large, black beetle with white spots and long antennae -- about the size of a Lowcountry palmetto bug -- hitched a ride on shipping pallets from China in 1997. Eating the bark, heartwood, twigs and leaves at different life stages, it has killed thousands of maples and other hardwood trees species in the country, mostly in the Northeast.

It could potentially be a threat to the Southeast, said Mary Douglass, supervisor of the USDA inspection office. "There would be plenty of host material for them," she said.

Sometimes 'blindsided'

While as many as 40 containers a day may undergo physical inspection in Charleston, insects are not found in or on all of them or their cargo. Most of the bugs intercepted are not determined to be a threat -- a pest that is not already established in the United States.

Of the 800 to 1,000 specimens taken to the USDA's lab here for identification per year, less than 4 percent turn out to be pests that are deemed "actionable," according to Switzer.

Most often, that means the USDA will oversee fumigating the shipment. But in some cases, the shipment is rejected and returned to the sender. Cargo can be, but rarely is, destroyed. An entire ship can be refused entry to a port.

In 2009, Switzer's team, using binoculars, spotted a quarter-sized egg mass on the underside of a ship's mast. They found nine more masses on the vessel, all laid by the dreaded Asian gypsy moth. It was one of their biggest finds, the first interception of the moth on a vessel on the East Coast.

Global trade has increased so much, "that is why we are seeing more of these problem pests come in," Douglass said. "We do focus on certain insects, but very often, the ones that become a problem are the ones we've never heard of."

She said the USDA has been blindsided by insects like the Emerald ash borer that pose no real danger in their native country but thrive and do harm in the United States because they have no natural enemies here.

"It's sort of like 'Jurassic Park.' Dinosaurs are alright as long as they stay on that island," Weaver said. "But no one can predict what it will do in a new environment."

Switzer said one of the highest-risk cargoes that surprises a lot of people is Italian ceramic tile. "We find weed seed, snails and hitchhiking insects," he said. It's not exactly clear why the tile is a magnet for trouble, Switzer said, and there may be multiple reasons. For example, it could be that the tile is loaded at night under bright lights that attract insects.

Within the past decade, global shipping regulations were implemented requiring that wooden pallets be treated for insects. The USDA used to see a lot more wood-borers, "but they are still a pretty big part of it," Douglass said.

In his lab, Weaver has stacks of drawers filled with boxes of bugs that he has meticulously pinned and identified, about 10,000 specimens total, all shapes and sizes. Some of the insects are iridescent blue, some a pretty shade of green, and many have striking patterns. The five-drawer bark beetle collection, "I'm kind of proud of," Weaver said.

"He has a great reference collection," Douglass said.

"I think what we do is very important," Weaver said. "It's in my head every day."

Teresa Taylor is the food editor. Reach her at 937-4886.