Invasive species are serious trouble, causing an estimated $120 billion in damage each year, according to the U.S. Department of Agriculture.
Keeping alien insects, animals, plants, seeds and pathogens from entering through the country’s 300-plus ports is the job of U.S. Customs and Border Protection (CBP). Every day, more than 2,300 specialists inspect shipping containers, bulk produce, wood packing material and passenger baggage delivered by airplanes, ships, trains, trucks and international mail.
Last year, CBP officers conducted 22,638,509 passenger inspections and 705,510 cargo inspections. They intercepted 155,247 pests — 66,857 of these were reportable or of high concern.
A CONSTANT BATTLE. CBP officers do an impossible job, said Bob Vander Meer, research leader at the USDA’s Agricultural Research Service in Gainesville, Fla. “It’s amazing we don’t have more invasive pest species in the U.S. already,” he said. The “downward pressure” is incredible given the high level of international trade and travel, said University of Georgia Entomologist Dan Suiter. Nearly 25 million shipping containers arrive at U.S. maritime ports and land borders each year, reports CBP.
High on the agency’s most-wanted list are forest pests like the Asian gypsy moth, emerald ash borer and Asian long-horned beetle, as well as the spotted lantern fly and Khapra beetle, a grain pest. The Khapra beetle is “impervious to fumigation and pesticides” and can remain dormant for a long time, said CBP Public Affairs Officer Stephen Sapp. If it were to “gain some sort of a foothold here in the U.S., you’re talking about a massive economic impact,” as it essentially would shut down U.S. grain exports, he explained.
Officers of CBP’s Atlanta Field Office, which covers Georgia, the Carolinas and parts of Virginia, have intercepted Khapra beetles 106 times in the past three years, said Raina Dodson, agriculture operations manager. “Most of those were in passenger baggage,” but they’re also found in bulk cargo, she said.
From January 2012 to 2015, the Atlanta Field Office intercepted 30,633 pests and diseases, Dodson said. These included Africanized bees, subterranean and drywood termites, 95 cases involving ants of “highest concern,” and other animals, noxious weed seeds, plants and fungi/diseases, said Dodson.
THE SCIENCE OF INSPECTION. Knowing what to inspect is “a science in and of itself” and is based on “a risk assessment of what’s coming in,” said Dodson. The “data-driven” analysis considers CBP’s history of interceptions, shippers’ logbooks and manifests, time of year, pest biology and high-risk commodities, she explained. CBP tracks national holidays so it knows when to expect spikes in passengers trying to bring in food products. It also monitors outbreaks in other countries, which can “literally force overnight changes in what can come in (to the U.S.) and what cannot,” said Dodson.
CBP officers can’t inspect everything, but “they are smart about it; they know who the troublemakers are in the world,” said Suiter. The agency knows, for instance, where the Khapra beetle is most common, and who puts fraudulent stamps on wood pallets, which must be treated for wood borers, he explained. CBP canines help inspect handbags and backpacks of low-risk passengers at airports.
When pests of concern are found by CBP officers and confirmed by USDA entomologists as requiring action, cargo is isolated and quarantined, fumigated or shipped back. Ships found to have Asian gypsy moths or egg clusters are sent miles offshore to be cleaned and then are re-inspected.
CBP works with shipping companies and airlines to develop best practices and trains partners to ensure compliance. “At the end of the day, it has got to be a collaborative effort between all of us,” said Dodson. People ordering shipments should demand a clean supply chain; if shippers cleaned up containers many problems would be eliminated, she said. Her officers once vacuumed 34 pounds of seeds adhered to the outside of a shipping container. Khapra beetles are found in dirt on the floor of containers because shippers don’t bother to sweep them out in their home country, she said.
YOUR ROLE. Every port has a pest risk committee of state, federal, university and business stakeholders. Dodson encouraged pest management professionals to take part in these meetings. “We’re all better if we leverage our skills and our abilities and our resources,” she said.
Because PMPs are “on the front lines,” it’s “extremely important” to keep your eyes open to pests that act or look differently, said Vander Meer. PMPs “see things before we would even know about them. That’s part of the major way in which we make discoveries about new ant species,” he said.
The first reports of kudzu bugs came from three pest control companies in northeast Atlanta, Suiter said. “If you see something that’s out of the ordinary, let your state entomology department know about it,” he said.
Mike Rust, entomologist at the University of California-Riverside, suggested PMPs carry a vial of alcohol, forceps and a paintbrush to collect samples for identification. Do this the first time instinct tells you a pest is different, not the sixth. Proper identification will help you control a pest faster; it also could prevent an invasive species from taking hold.
Don’t Let Competitors Get the First Shot at Your Profits!
Environmental Delivery Systems is a world leader in the design and production of mechanical aerosol generators and custom application equipment. The products and services we offer continue to provide pest management professionals with unmatched quality and dependability essential to their success.
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With its discreet design, the VECTOTHOR SPARROWHAWK is ideal for smaller offices, cafés, restaurants, and shops where your patrons sit and you want to discreetly eliminate troublesome flies.
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The Gilbert® 2000GT Flying Venus™ flytrap from Gilbert Industries combines beautiful design with industry-leading effectiveness, creating a powerful tool for pest management professionals. The thin 2¾-inch design hugs the wall beautifully, creating an elegant ambiance, while secretly providing 24-hour, non-stop, silent capture of filthy, disease-carrying flies. It goes unrecognized in elegant dining rooms, luxurious hotels and hospital hallways. The 2000GT Flying Venus flytrap comes in four beautiful finishes. It is EPA registered, UL listed, CSA approved and meets FDA and USDA standards.
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Get lightning fast control of cockroaches with InVict™ Gold Cockroach Gel. Formulated with a unique bait matrix and 2.15% imidacloprid, this bait achieves outstanding palatability, value and results, giving you an unfair advantage. Roaches begin dying in as little as 20 minutes after eating the bait with proven secondary kill when roaches are exposed only to carcasses and droppings of roaches that ate the bait. InVict Gold has unique food-grade attractants that are intentionally different from other popular baits, making it the ideal choice for bait rotation to prevent bait aversion. It’s also formulated without the eight most common food allergens for sensitive applications such as food plants, schools, child-care and health-care facilities. InVict Gold is available in 35-gram syringes boxed individually or in four packs and a 300-gram “Big Gun” syringe that fits in a standard caulking gun.
The Thermal Remediation® model EBB-120NB bed bug heat treatment box truck package has arrived! This box truck stores 12 EBB-460B heaters, allowing your company to heat treat up to 3,600 square feet of space. The truck is sold separately.
EBB-120NB Box Truck Package Includes:
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For further product details and pricing, call (800) 836-7432 and ask for the Thermal Remediation® team or visit ThermalRemediation.com.
Professional series traps from Tomahawk Live Trap are built to withstand daily abuse from both animals and operators alike. These traps feature ½” x 1” wire mesh throughout the entire trap. This tight mesh pattern not only gives the trap unbeatable strength but also minimizes property damage from trapped animals and prevents animals from reaching in and stealing bait from outside of the trap. All Professional trap models that are 7Wx7H” or larger also feature a pan protector bar to eliminate trip pan damage from trapped animals.
Tomahawk manufactures many different sizes and styles of professional grade traps for different animals and situations. Sizes range from 5Wx5H” traps for chipmunks and squirrels up to 12Wx14H” traps for very large raccoons and woodchucks. Styles include the following: standard traps with one trap door, traps with one trap door and a rear release/bait door, flush mount traps, multipurpose traps that feature built-on nose cones, traps with two trap doors and a new specialty trap designed by the NWCOA for roof mounting and attic work.
After 90 years in business, Tomahawk Live Trap is still dedicated to continuous improvement and customer satisfaction. Tomahawk manufactures all of its traps and cages in the USA at their facility in Wisconsin. Every single trap is inspected for quality and all come with a manufacturer’s guarantee against defects. Tomahawk Live Traps are recognized as the highest-quality live traps by wildlife control professionals, animal control officers, researchers and government organizations around the world.
PCT is proud to offer the pest control industry FREE online label training through the PCT Distance Learning Center.
Created by Board Certified Entomologist and consultant Stoy Hedges, the courses use photographs, video clips and reference materials to challenge users’ knowledge, experience and problem-solving skills for a wide range of products and pest problems. Accessible by PC, tablet or smartphone, Distance Learning Center training is presented in modules designed to take a half-hour to an hour to complete. This brevity gives individuals the opportunity to fit this education in whenever their schedules allow — even during breaks or lunchtime. And if a user needs to stop while taking a course, no problem: He or she can close the program and pick up at the point left off later. Each label course is designed around reading and interpreting a specific pesticide product label, covering all aspects of the label — from trade name, target pests, hazards and first aid to areas for treatment and directions for use.
Visit https://training.pctonline.com to get started, and return frequently as new label training modules are being added monthly.
PMP Discovers Hex-Pro® is a Win-Win
Is your company interested in increasing retention, reducing labor and making customers happier? Triangle Pest Control in Raleigh, North Carolina, accomplished all three of these goals with the Hex-Pro® System. When their termite monitoring product was discontinued, Hex-Pro seemed like the way to go. And that decision has made a great impact on their business, says Jesse Rehm, chief operating officer.
Because Hex-Pro is both a monitoring and baiting system, the advantages outweigh termite monitoring alone. Since Triangle Pest Control bundles termite monitoring with general pest control, that used to mean sending out a termite technician to do a liquid termite treatment if mud tubes or other termite activity were found by the general pest control technician. Now, the technician who discovers feeding in the stations is the one who baits the station with Hex-Pro that same day, allowing for a quick solution to a potentially big problem.
“The benefit with Hex-Pro was that now we didn’t have to send the termite technician out to do a liquid spot treatment if there was evidence of termites in a station,” says Rehm. “With Hex-Pro, the technician can take care of the problem right there. It has completely eliminated having to make a second service call. So it’s really saving us money.”
According to Rehm, Triangle Pest decided to use the Hex-Pro® System over competing brands.
“When we put our Triangle Pest seal of protection on a home, we want to be 100 percent confident,” he explains. “Hex-Pro helps us do that. Many of our customers show hesitation when we mention the installation of a termite monitor. But once we show them how well the stations blend into their landscaping, it’s no problem at all. We also make a point to provide services that are reduced risk and protect our customers’ homes.”
While customers aren’t noticing much difference between the two products, Hex-Pro has definitely made a difference in his business, Rehm says.
“We have a higher retention rate with this service,” he says. “Hex-Pro gives us an extra line of defense so we can address the termite problem before it becomes a structural problem. We’re seeing the benefit of reducing the trips to the house for servicing and the customers are still getting the termite protection they want. It’s a win-win.”
To learn more, contact your Hex-Pro distributor. Distributors include: Ehrlich, Forshaw, Helena Chemical, Oldham, Residex, Rhodes, Target, Univar, Veatch and Winfield.
®Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow
Inside the Back River sand filtration facility, home of the largest communal web of orb-weaving spiders ever recorded.
In late October 2009, the managers of Baltimore’s primary wastewater treatment plant sent out an urgent appeal to the Department of Entomology at the University of Maryland for assistance with what they described as an “extreme spider situation” in their sand filtration facility. The building is enormous, occupying a space of about four acres under a single roof — equivalent to three football fields — but with no side walls. Its purpose is to serve as an advanced, “polishing” step in the purification process, as partially treated water slowly percolates through 48 sand-filled beds prior to being discharged into the Back River, a tributary of the Chesapeake Bay.
I was part of a five-member, interagency team of arachnologists, urban entomologists and pest managers that visited the facility the following month and witnessed a spectacle that none of us had ever seen before, nor could even immediately comprehend. Peering into the dim, cavernous interior, we saw a vast world literally swallowed up by webbing. Great masses of it engulfed the equipment, blotting out much of the machinery from view. Endless sheets of it blanketed the ceiling, and in one spot had actually pulled a massive 8-foot fluorescent light fixture out of alignment (Figure 1). In places where the intrepid crew had taken brooms, poles and other tools to sweep the web away to create some access, the material lay piled on the floor in dirty coils as thick as a firehose.
Figure 1. Several of the facility’s suspended light fixtures had been pulled out of alignment by expanses of webbing anchored to the upper walls. This was the most conspicuous example.
And throughout it all, there were spiders beyond imagination, embedded in their communal silk by the millions, dangling down on drop lines everywhere in response to any disturbance. What was happening here?
THE STUDY. Scientists are no more immune from astonishment than anybody else, but their greatest distinguishing characteristic is the urge to measure anything that interests them. For what would seem to be an impossible mathematical task, our team used a process that is often termed “Fermi estimation,” named for the Nobel Prize-winning nuclear physicist who tackled such problems by systematically breaking them down into a series of more manageable pieces. We were fortunate that the sand filtration facility is a modular structure, consisting of various repeating architectural units. By first calculating the extent of webbing throughout representative units, then collecting standardized samples of the silk masses and counting the number of spiders they contained (Figure 2), approximations could be made of both the extent of the webbing and the spider population it contained. After weeks of painstaking analysis of the collected data, we arrived at the following totals:
The unbroken expanses of sheet-like webbing attached to the ceiling covered about 10,443 square yards, i.e., a little more than 2 acres.
The three-dimensional clouds of webbing totaled about 5,444 cubic yards, or roughly equivalent to the capacity of 23 standard railroad boxcars.
The number of spiders living in the facility on the day we took the samples was more than 107 million individuals.
How reliable are these numbers? We’re confident that the amount of silk is firmly in the ballpark. Using blueprints, onsite measurements and more than 300 photos taken throughout the facility, calculating the extent of webbing was fairly straightforward. But the quantity of spiders, particularly because so many were tiny hatchlings, should be regarded in light of the cardinal rule of Fermi estimates — it is the order of magnitude (power of 10) that is far more critical than the specific integers. In other words, based on the data we collected, the most conservative way to state the size of the spider population occupying the building is that it was somewhere in the hundreds of millions.
Figure 2. Ben Pagac and Jon Coddington examine a detached section of what was virtually a continuous sheet of webbing over much of the facility’s ceiling. A pole pruner with a saw blade was used to obtain standard samples of this laminar silk for analysis.
After writing up the results, our study was published in the fall 2010 issue of American Entomologist, a quarterly magazine devoted to subjects of general interest to the entomological community. As with the overwhelming majority of scientific reports in the world, it promptly lapsed into obscurity. But in 2014, out of the blue, a startling and somewhat bizarre event occurred. In celebration of the Halloween season, writer Gwen Pearson of Wired magazine (a publication commanding a considerably greater audience than American Entomologist) resurrected a short, humorous story on the Baltimore megaweb that she had originally posted on her pseudonymous “Bug Girl” blog back in 2010. Quoting one of our introductory statements about how unprepared we had been for the sheer scale of what we saw, Gwen reminded her readers that it had been “written by five mid-career professional entomologists and arachnologists. If they were a bit startled by the size of the web…it was a big freakin’ web.”
In a flash, the Wired piece was picked up by social media around the globe, trending on hundreds of sites ranging from YouTube to the New York Daily News. What initially was amusing quickly turned unsettling as my inbox and voicemail filled up overnight with urgent requests for interviews from reporters, TV producers and filmmakers from as far away as Amsterdam. Everyone suddenly seemed to have an extreme obsession with extreme spider situations.
Predictably, the flare of attention burned out in less than a week, a vivid demonstration of Andy Warhol’s “15 minutes of fame” quip that I never want to experience again. Other than an enduring presence in one of the Internet’s more obscure corners (check out “giant Baltimore spider web” on Google), all that remains of the curious episode is a collection of colorful comments on the story that I gleaned while surfing through the blogosphere. A few of my favorites:
“I, for one, welcome our new arachnid overlords…”
“The agreement with the union promised a fly-free work environment. What’d you expect?”
“The worst part was when they lost count at 105,226,717 and had to start over.”
And, of course, dozens of suggestions for control along the lines of “I say we take off and nuke the entire site from orbit.”
THE SPIDERS. At the center of the Baltimore megaweb saga, of course, are the extraordinary creatures that created it. A total of 31,194 individual spiders (real specimens, not estimates) were extracted from the web samples, preserved and identified. Although nine genera in six families were represented, the webbing was almost entirely the product of only two species, Larinioides sericatus (which was known by the name of sclopetarius at the time) and Tetragnatha guatemalensis. Composing nearly 5 percent of the total specimens, the burly L. sericatus is a well-studied, markedly synanthropic spider that is strongly associated with man-made structures along rivers and lakes and thus would be expected to turn up at a wastewater treatment plant. Commonly named the “bridge orb-weaver,” it has been experimentally shown to actively choose locations illuminated by artificial light.
Nevertheless, L. sericatus was still a relatively minor player in the facility. The overwhelmingly hyperabundant webmaster was T. guatemalensis, a species with no common name and whose life history is still virtually unknown to biologists. Typical members of its genus are slender, very long-legged spiders that are fittingly referred to as “long-jawed orb-weavers,” due to their swollen, conspicuously protruding chelicerae (apparently an adaptation for mating). However, calling this particular species the “Guatemalan long-jawed orb-weaver,” as some writers do, makes about as much sense as “German cockroach” or “Norway rat.”
Ranging as far north as Nova Scotia (but far more likely to be encountered in Florida and south Texas), its name signifies only that it happened to be originally described from a specimen collected in Guatemala. Now having dramatically revealed itself in Baltimore as well, its domination of the sand filtration ecosystem was nothing less than spectacular, accounting for about 92 percent of the collected specimens. Of the total 28,623 individuals in our T. guatemalensis sample, 84 percent were hatchlings. In fact, since these tiny spiderlings began actively dispersing on air currents throughout the laboratory as soon as the web sections were removed from the collecting bags, it is obvious that a substantial number eluded our census.
What is it about these two species? When observed under typical circumstances, in which the solitary spiders are spaced apart throughout a given habitat, their web architecture is well within the normal bounds for orb-weavers. Those of L. sericatus are large, vertical orbs with relatively few spokes and support strands, while T. guatemalensis constructs quite fragile snares that are usually diagonal or even horizontal — nothing at all to suggest any particular aptitude for erecting colossal “arachnotopias.”
And yet, as it turns out, both species share a highly distinctive and critical behavioral characteristic. When circumstances are favorable and the spiders find themselves in increasingly close quarters, they display an unusual tolerance not only for others of their kind, but other types of orb weavers as well. As densities build up and individual webs begin to spatially overlap, a growing number of non-orb silk lines are produced, linking webs together and blurring their original boundaries. Bit by bit, spiders begin venturing away from their original spots (laying down more silk as they go) and wander further into what increasingly becomes a truly communal structure. Over time, the scale of the phenomenon is limited mainly by three factors: availability of food, availability of a framework (manmade or vegetative) on which to anchor the webbing, and the absence of severe weather that would destroy an expanding silken city.
Perhaps most surprising is how often this type of megaweb occurs both in nature and in or on human structures. Although the example in the sand filtration facility was far greater in magnitude than any previously recorded aggregation of orb-weavers, it was by no means unique. Still the most celebrated instance was a huge expanse of webbing enveloping trees in 2007 along a woodland trail at Lake Tawakoni State Park in Texas. Dubbed by the media as the “giant Texas web,” and publicized by exceptionally haunting photographs of the spectacle, the primary spider involved was also T. guatemalensis, as well as another Larinioides species. The online response to the story was a good example of inadvertent crowdsourcing in the interests of science, as photos and descriptions of other large masses of tetragnathid-dominated webbing on vegetation began to proliferate on the Web (alright, I finally said it). Lesser known examples of Larinioides-dominated megawebs (all three U.S. species display the same knack for diminished aggression toward neighbors in times of plenty) can be found in the arachnological literature. The two most extreme involved the interior of a power plant wheelhouse on a lake in Alberta and the exterior of an arena on the Ohio River. And so, what appears to be the universal causal agent of these events comes into focus.
Figure 3. A cloud of midges dances over the roof of the facility in mid-December 2009. Although air temperature was about 50°F, the water temperature in the sand beds from which the midges were emerging was 10 degrees warmer.
THE SYSTEM. Obviously, spider populations, gigantic and otherwise, are driven by prey abundance. Less apparent as the keystone factor for pushing the envelope of gregarious behavior among normally solitary species is the proximity of significant bodies of water. So far, no orb-weaver megaweb has ever been recorded that was not close to a lake or a river. Indeed, several lakes in the arid Southwest, the only water around for miles, are famous for extraordinarily dense spider aggregations along their shores. Perhaps the most well-known of these is Walker Lake in Nevada, which hosts massive billows of interconnected webbing packed with Western spotted orb-weavers (Neoscona oaxacensis) every summer. However, since the tallest vegetation over most of the area is sagebrush, the necessary framework to support a towering, integrated megaweb is not available.
Of course, what water brings to the system is an incomparable bounty of spider food. Only large aquatic habitats are ecologically capable of reliably producing the mighty “blooms” of flying insects necessary to continuously satiate the appetite of an epic assemblage of orb-weaving spiders, thus triggering the pronounced complacency towards neighbors that allows communal behavior. And of all of the many different types of insects that live in freshwater as immatures and mate in the air by the billions as winged adults, non-biting midges in the family Chironomidae — sometimes called “fuzzy bills” in the mid-Atlantic, due to the conspicuous, plumose antennae of the males — reign supreme as the dominant prey for orb-weavers over much of the globe. Our story is thus fundamentally a tale of flies.
For some reason, the hordes of midges that routinely swarm over the Back River and along its banks, driving residents, boaters and marina operators crazy with their sheer numbers, started to get unusually dense a few years prior to the sand filtration facility’s extreme spider situation. The river has long been degraded by sewage, storm-water runoff and other pollutants from urban development throughout its watershed and is considered to have some of the poorest water quality in the Chesapeake Bay region. Some midge species thrive in such conditions since they are highly adapted to living in muck that is virtually anoxic. In an effort to understand why the midge population had exploded, sampling of their tiny, bright red larvae (often called “bloodworms”) from the river bottom by Baltimore County natural resources personnel coincidentally began in the autumn of 2009, just as the megaweb was being documented. Densities of up to 6,000 larvae per square meter were recorded. Normally, this type of staggering productivity would be a boon for fish and other predatory aquatic organisms. In their absence, due to the exceptionally noxious water quality, the greatest beneficiaries were the spiders.
As it turned out, the sand filtration facility’s infestation had an additional, ironic twist. The fact that its overarching roof provided the arachnid community with shelter from the elements, allowing the greatest possible expression of web construction, has been noted. But the building’s second critical asset was that it reliably and continually generated a significant portion of the spiders’ food supply. As we eventually discovered, and which has been extensively documented in other sewage treatment plants as well, the warm, nutrient-rich sediments of the huge sand beds were teaming with blood worms. The facility was truly a self-contained, gigantic spider-rearing biosphere, producing an inexhaustible food supply that exceeded the ability of any predator to deplete (Figure 3). It wasn’t just located in optimal spider habitat — it WAS the habitat. Year after year, the arachnotopia is renewed mainly from egg sacs deposited onsite (Figure 4) and fed mainly on midges grown onsite.
Figure 4. Spider egg sacs packed together on the underside of a light fixture in the plant, February 2010. Most of these are from L. sericatus — the smaller but far more numerous egg sacs of T. guatemalensis were concentrated on the upper walls and ceiling of the facility. Although difficult, removal of egg sacs during the winter is theoretically one of the most effective tactics to control spider numbers for the following year.
The inability to control a pest population’s food supply significantly limits the available management options. Furthermore, the use of pesticides is clearly not an activity that is appropriate for a plant that discharges treated water into an already troubled river. The strategy that has so far prevented a return of the astounding conditions of 2009 is simply treating web and spider removal in the facility as a recurring custodial function that is accomplished by basic mechanical means.
Besides, the building has become something of a unique scientific resource. Four years after the megaweb study, the Smithsonian Institution members of our original team requested a return visit for an unusual purpose. One of the National Museum of Natural History’s newest and most exciting megaprojects is termed the Global Genome Initiative, whereby genetic samples of as many of the Earth’s life forms as possible are flash frozen in liquid nitrogen for future DNA sequencing — essentially taking the museum’s preservation and study mission to the next level. The desired sample size to experimentally determine the best protocol for doing this is 280 specimens of the same species. And when it comes to spiders, where could this be carried out in the most efficient manner? On Aug. 6, 2013, despite radically reduced webbing in the sand filtration facility, four researchers easily collected 437 T. guatemalensis in little more than an hour. As the flagship arachnid in the Smithsonian’s genome study, it’s safe to say that this remarkable species’ relative anonymity is rapidly coming to an end.
Just when I thought they were through with me they reappeared, sliding silently through walls that appear solid (but the quantum physicists know better). Suddenly they are everywhere. Staring at me from the rim of a glass when I open the cupboard. Calmly observing me as I sleep from my sweetheart’s framed photo on the bedside table. Waiting undiscovered in the tub until I fling back the shower curtain. Peering at me from behind the mini-blinds.
As you no doubt suspect, these are not your standard Hollywood issue sci-fi ETs. No large vacant eyes gazing out from an oversized cranium balanced precariously on a spindly neck and a child-sized humanoid form. Quite the opposite—they have the build of a bouncer, with a broad, flat trunk and wide sloping shoulders. The head is insignificant, practically an afterthought. Small, dark eyes scan from behind two banded antennae waving like the arms of a 1960s television robot warning Will Robinson of danger.
These aliens aren’t otherworldly galactic hitchhikers, though. They’re Earthlings. Opportunistic vagabonds who likely stowed away in packing crates shipped from the other side of our planet.
There are some native North American members of the Pentatomoidea clan, known more commonly as shield bugs (because of their triangular shape). Some species are quite beautiful but this particular variety is a real stinker.
Brown marmorated stink bugs (BMSBs, Halyomorpha halys) are about 1.7 cm (0.7 in) long, with alternating dark and light markings along the sides of the body. Despite the name they also come in shades of taupe, gray and black. Glands on the underside of the thorax and the top of the abdomen release an acrid scent described by some as similar to coriander. Used as a defense mechanism, the odor response can be triggered by injury and nearly any kind of movement. As a result, some homeowners resort to using a dedicated vacuum to beam the beasties up into a sealed chamber where they and their stink can be contained until dispatched.
BMSBs were first noted on this continent in 1998 near Allentown, Pa. In less than 20 years they have fanned out to more than 40 states. Their population continues to grow dramatically, aided by prolific fecundity. In some parts of the Northern hemisphere, stink bugs typically produce four generations per growing season but an early spring and extended summer can increase that number to six. The female deposits a cluster of about 25 eggs at weekly intervals. Red or orange tick-like nymphs emerge, experiencing five molts (instars) as they metamorphose into adults, at which point they follow in their parents’ footsteps and begin propagating too.
While not classified as social insects, when temperatures drop stink bugs leave established encampments in orchards and agricultural fields. They march and fly by the thousands, Borg-like, toward hospitable interior environments where they will overwinter and get ready for the next wave of colonization. This migration is largely undetected by the human population until it’s too late and our homes have become hostels for a six-legged horde.
Because they are an introduced species, BMSBs have no natural predators in the U.S., although a 2012 study suggested some of our native wasps and birds are adapting to this new food source. That might sound like good news to the agricultural crowd but — speaking only for myself here — I’ll choose stink bugs over wasps as roommates any day.
Sure, sharing one’s home with a couple hundred uninvited guests isn’t anyone’s idea of fun but BMSBs aren’t a threat to my canine companion or me. Truth is, they aren’t the slightest bit interested in mammals and have never asked to be taken to my human leader. It’s my houseplants they want. The bird nest fern, philodendron and pepperomium have become their helpless research subjects, probed with piercing proboscises for the fluid samples upon which the aliens feed.
Hundreds of hours playing video games in preparation for space invaders and all I can do to protect the leafy green inhabitants of my red brick realm is fire up my Dustbuster.
And I know more are on the way. Resistance is futile.
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