Spider management is an important portion of the pest control dollar and there are numerous chemicals on the market for their control. Many of the pesticides used around homes are water-based, because they don’t have an offensive smell and don’t leave an oily residue to which dust and dirt adhere (as do oil-based pesticides). However, this leads to an interesting conundrum. The external silk layers of many spider egg sacs are hydrophobic; that is, they repel water. This makes sense because when a spider lays its eggs, it wants to protect them from environmental threats such as rainfall. But what does this mean for the PMP? If a pesticide uses water as a carrier, does its active ingredient (AI) impact the eggs within an egg sac?

In the first series of tests, we chose five commercially available, water-based pesticides commonly used by PMPs. (The product names aren’t critical, but they are listed in the publication referenced at the end of this article.) We also chose one aerosol product that contained petroleum carriers to see if it had a different effect than the water-based pesticide products.

Egg sacs were treated by spraying pesticide on one side, as would likely happen in the field, and left to emerge (usually by the 20th day). If nothing had emerged by the 30th day, the sacs were dissected to examine the contents. We also set aside egg sacs that were untreated to serve as a control group. We considered a pesticide to be effective if none of the 18 egg sacs had spiderling emergence.

TEST RESULTS. In the first tests, we found that none of the water-based pesticides prevented the spiderlings from emerging from all the sacs (Figure 1, page 106). In fact, there was no statistical difference between emergence from water-based pesticide-treated sacs and the untreated controls. In contrast, the one petroleum-based aerosol (AI: cyfluthrin) that we tested killed the contents of all 18 sacs.

To test this penetration aspect, in the second tests, we paired pesticide products that had the same active ingredient but different carriers. One pair of products contained cyfluthrin and the other contained deltamethrin. All four products were mixed with red stain that would allow us to confirm if the carrier had penetrated the silk layer and contacted the eggs inside the sac. We used sacs that were less than eight days old so that we would be testing only sacs containing eggs.

As shown in Figure 2, egg sacs were completely dipped in the water-based pesticides. Petroleum-based aerosols were sprayed into a vial to which stain was added, and 10 microliters of the stained pesticide were applied to the side of the egg sacs. The sacs were left for 30 minutes then dissected.

There was greater survival in the water-based ready-to-spray pesticide tests than in the petroleum-based product tests, but it was still statistically better than the other water-based compounds used in the first test.

There was some differential response inside the sac: some pesticides killed the contents of the one-day-old sacs while they were eggs, while some one-day-old sacs treated by other pesticides had spiderlings inside when dissected. These latter sacs showed that, although the pesticide prevented the spiderlings from emerging (i.e., it showed sufficient control), it didn’t stop them from hatching from eggs to spiderlings.

So, if a stockpile of egg sacs from a spider like the brown widow is discovered in the corner on the underside of a picnic table, the PMP may want to use a non-water-based pesticide for spot-treatment of the egg sacs.

A FINAL WORD. Although we used the brown widow spider as a model for the treatment of most spider egg sacs, this may be unnecessary for some spiders, such as cellar spiders or daddy longlegs, which are urban pests; they carry their egg sacs in their fangs and cover them with only a few strands of silk. If you are applying pesticide to control these spiders, it would seem that the water-based pesticides would work just fine because there is no silk layer to protect the eggs.

Reference: Vetter, R.S., J. Tarango, K.A. Campbell, C. Tham, C.Y. Hayashi and D.-H. Choe. 2016. Efficacy of several pesticide products on brown widow spider (Araneae: Theridiidae) egg sacs and their penetration of pesticides through the egg sac silk. J. Econ. Entomol. 109: 267-272.

Rick Vetter is a retired arachnologist from the University of California, Riverside (UCR). Dong-Hwan Choe is an UCR assistant cooperative extension specialist and assistant professor of entomology.

One of the most critical tests of a pest control company’s genuine commitment to protecting the planet — “guardians of the environment,” as the National Pest Control Association so effectively phrased it in the 1990s — is how its technicians are instructed to handle complaints about non-harmful, overwhelmingly beneficial creatures that are nevertheless viewed with alarm by much of the general public. How do we reconcile our professional imperative to educate about the natural world with a property owner’s prerogative to control whatever he or she considers a pest?

Many of these awkward situations involve species with a scary demeanor masking a benign temperament — black rat snakes and cicada killers immediately come to mind. But to my way of thinking, the pinnacle of common pseudo-pests are the smaller mining or digger bees in the families Andrenidae, Halictidae and Colletidae. Diminutive, fuzzy and industrious, they hardly seem like the type of animal that would provoke a call to the exterminator. But they tend to appear suddenly and in large numbers, coursing back and forth over their nesting grounds and, to the average layperson, closely resembling truly pestiferous yellowjacket workers (also often unfortunately referred to as “ground bees”) which become numerous much later in the season.

In an ideal world, the technician answering this type of call would be knowledgeable about the fine points of Hymenoptera biology and would point out four critical truths to the client: 1) most of the bees flying around are totally harmless males, which cannot sting; 2) stings by the non-aggressive females are extraordinarily rare and only happen by improbable accident; 3) the bees will disappear in a few weeks in any case; and 4) most important, these insects are not just inoffensive but providers of what are now fashionably referred to as “ecosystem services” to mankind because of their vital role as pollinators. In real life, on the other hand, it is a highly unusual pest control firm, no matter how enlightened the management, that will actually walk away from a request to treat an aggregation of solitary bees.

It’s a thorny issue, but there is, in fact, a compelling and relevant way that we can work towards balancing the ledger with a gesture of pollinator promotion that is a natural fit with our industry. We can, at least symbolically, give homes back to the bees.

TRAPS, BINDERS & HOTELS. Providing artificial nesting cavities for solitary bees and wasps is a venerable pursuit that has evolved three basic lineages over the years. At first, the emphasis was on basic biological study. Published accounts go back to the legendary naturalist Jean-Henri Fabre in the early 1900s, who used reeds for the purpose and throughout the first part of the century several researchers followed suit with a variety of methods. However, no person did more to popularize the concept than Karl Krombein, one of the world’s great hymenopterists, who in 1953 began systematically setting out pine blocks with borings of several different diameters to lure in solitary wasp and bees species that normally would either excavate tunnels in natural plant material or (much more often) use pre-existing cavities, such as hollow stems or the galleries of other insects, in which to nest. The blocks were then split lengthwise to inspect the contents and subsequently taped back together for re-use. His unique masterpiece, Trap-Nesting Wasps and Bees: Life Histories, Nests and Associates (Smithsonian Press, 1967) provided 11 years’ worth of data gleaned from more than 3,400 traps utilized by about a hundred species and almost as many parasites and predators that exploited them. It is still the definitive reference work on the subject.

At about the same time that Krombein was perfecting techniques that used artificial nest sites purely for observational purposes, an entirely different application was being explored by agricultural researchers in the Western U.S. and Canada. The goal was to create a system to propagate large numbers of certain bees in the family Megachilidae so that they could be efficiently deployed as pollinators of fruits, vegetables and forage crops. Starting out with bundled paper straws, the approach eventually adopted by commercial suppliers was to route out numerous adjacent channels on large boards that were then bound together to form cylindrical tunnels — thus termed binders or binder boards — to produce transportable and stackable containers for housing a concentrated bee population. (Nowadays, molded plastic boards also are used.) Two megachilid species have been the superstars for this industry. The tiny, introduced alfalfa leafcutter bee (Megachile rotundata)was the first and by far the most successful, use of a solitary bee for managed pollination in North America. Domiciles for this species that are hauled into alfalfa fields can be as large as truck trailers and accommodate many thousands of bees. The native blue orchard bee, or orchard mason bee (Osmia lignaria) is used primarily to pollinate fruit and berry crops in the spring, but is not commercially available at anywhere near the scale as M. rotundata.

The third iteration of man-made solitary bee condos arose only recently as a result of growing societal awareness and concern over the decline of many species of pollinators as a result of increasing environmental degradation. Starting at the end of the 20th century and rapidly gaining traction during the first decade of the 21st due to the sudden onset of colony collapse disorder in honey bees, the widely publicized “pollinator crisis” spawned what might be termed the “pollinator movement.” Common expressions of interest and support for these indispensable, winged components of the ecosystem include reduced mowing along highway margins and median strips, a growing interest in small-scale beekeeping and a rebranding of the original butterfly garden concept to emphasize bee-friendly plants in public landscapes and private gardens.

In addition, a new type of green consumer product made an appearance — small scale, novelty versions of the commercial bee boards, emphasizing the conservation of native bees and marketed in such venues as nurseries, home and garden centers, wild bird stores, flower shows and craft fairs. Since most are relatively simple to construct, a variety of do-it-yourself plans quickly became available as well. These objects are called by several different names, but one of the most common terms is “bee hotels.”

SENDING A MESSAGE. The earliest bee hotels were usually nothing more than wooden blocks about the size of a small bird house, with rows of drilled holes and a simple roof. They now come in all conceivable shapes and sizes and range from polished, “designer” models to much cruder, no-frills assemblages. Many hotels have an array of different cavity widths and utilize multiple construction media, including bundles of hollow stems, cardboard tubes or pieces of bamboo; drilled pieces of wood; and even ornamental masonry blocks. On the cutting edge, the trend is for increasing scale — a few of the larger creations are ornate walls on the same magnitude as commercial M. rotundata domiciles — but also for esthetic creativity.

Indeed, in its most exalted state, the discipline has emerged as a new type of outdoor art form. Artificial bee nesting sites have become the latest manifestation of what might be termed “ecosculpture,” imaginative but functional creations of natural materials that are allowed to weather and ultimately degrade. Many of them are exquisitely beautiful or striking examples of outreach to enhance public awareness of pollinators. The University of Maryland campus in College Park, for example, is home to a contoured, 24-foot “bee habitat” made of cob (a clay/sand/straw mixture) with holes of various sizes poked with chopsticks during its construction. Embedded in this wall is a “bee booth,” a wooden cabinet enclosing curved, routed tunnels covered with an acrylic panel and wired so that visitors can not only observe, but listen in with headphones as the occupants go about their business. It certainly takes the original trap nest concept to an entirely different level.

Newcomers to this exuberant subculture should be aware of a few caveats:

1. Solitary Hymenoptera that occupy bee hotels are mostly species that prefer to nest in pre-existing, above-ground cavities. Mining or digger bees usually excavate their own nesting holes in the ground. Despite a few exceptions, these are generally two different groups of organisms.
2. Bee hotels are utilized by what are often termed “wild pollinators,” as opposed to the domesticated honey bee and, as such, are all firmly in the “beneficial” column. But they are certainly not all “native” bees, as is often claimed. Studies in California and Toronto have revealed that roughly three-quarters of bee hotel occupants are actually introduced species.
3. On a functional basis, bee hotels as yard art are definitely not a miniaturized equivalent of the intensely-managed commercial operations that mass-propagate megachilids for agricultural service. The latest critique on hotel efficacy by J. Scott MacIvor and Laurence Packer, entitled “‘Bee hotels’ as tools for native pollinator conservation: a premature verdict?” (PLoS ONE, March 18, 2015) found evidence that the devices served to concentrate brood parasites, predators and diseases and should not be automatically regarded as playing any measurable, positive role for local populations of their target species.

I don’t regard this business practice as inconsistent in any way — it is an astute public relations strategy for sending a powerful message that our professional ethos consists of a far broader world view than simply exterminating things. The same goes for vigorously supporting the pollinator movement and its conspicuous emblem of the bee hotel. Don’t just be a bystander as society evolves around you. Check out these fascinating creations today!

The author is entomologist and national IPM coordinator for the Public Building Service, U.S. General Services Administration (GSA), Washington, D.C. The opinions expressed herein are the views of the author and do not necessarily reflect the official policies or positions of GSA.

Rats & City Alleyways

An attractive harborage and foraging site for rats.

There is often a mythical air about city alleyways and rats. Some people are afraid of alleyways, believing rats have become a natural inhabitant of these locations. Although this is not true, some city alleyways are prone to rat infestations, but only if humans allow it. The typical city alleyway by its specific “urban ecology” is an attractive harborage and/or foraging site for the Norway rat. Why is this the case? There are a number of reasons:

1. PROTECTIONS FROM PREDATORS. City alleyways tend to be long and narrow. Such a spatial arrangement allows rats to escape quickly to the safety of the walls on either side of the alleyway when they hear frightening sounds or detect the presence of a predator in the alleyway. In addition, alleyways are dark and quiet even during daylight hours. Rats are generally attracted to such shadowy locations to escape detection from their enemies.

Many foraging rats have a good chance of locating at least some food in a typical city alleyway. Many “back doors” of restaurants and apartments in inner-city areas open up to the alleyway, and thus these corridors are where trash cans, grease receptacles and Dumpsters are installed. Thus, food scraps and often piles of kitchen refuse in plastic bags commonly occur in alleyways. Wind-blown trash and food wrappers from the nearby streets often collect in the alleyway. If the alleyways are frequented by the homeless, they may leave trash and food scraps that are later used by rats.

3. EXCELLENT HARBORAGE. Many of the older alleyways in cities are in a state of disrepair. Deteriorating brick foundation walls and alleyway pavements provide ample opportunities for rats to hide or establish burrows. In addition, old furniture, equipment, pallets and other types of junk are often discarded into alleyways, providing daily cover or ideal long-term rat harborage. Alleyways also are often protected alcoves from cold winds and shaded against the direct hot sun during summer.

4. REDUCED CLEANING EFFORTS EXACERBATE THE PROBLEM. Because some alleyways may be or are perceived to be frequented by people involved in “shady” dealings (e.g., drug dealing, gang members, etc.), alleyways are often avoided by people. In these situations, trash may be dropped out of windows above the alleyway, creating a direct food source for the rats and/or the alleyway remains uncleaned by local residents and city employees concerned for their personal safety. Of course, not all city alleyways fit this profile. In well-managed areas, alleyways may be peaceful, clean and rat-free private “courtyards” that are thoroughly enjoyed by the residents. Again, management of the specific urban environment dictates any area’s vulnerability to pest populations.

Neophobic Rats or Departed Rats?

© Vitalii Hulai | Thinkstock.com

In well-established neighborhoods with abundant amounts of lush landscaping, palm trees and viney fence rows running along and connecting several backyards, roof rats sometimes enter and explore homes and commercial buildings in intermittent spurts. For example, rats living in the crowns of palm trees may venture down and enter beneath “closed” attached garage doors of several homes on a block to make “exploratory pass throughs” looking for food. Or roof rats from several properties away may visit a garage or an attic for an evening or two, leave behind some fecal pellets, and then not return to the residence or part of the street for several days or weeks, or they may never return.

Upon hearing the rats overhead or noticing rat scats, homeowners set out some traps or rat bait or call in a pest management professional. When the traps or baits are not interacted with, it may be wrongly concluded in these cases that a “neophobic” rat is living on the premises, but avoiding the traps and baits. Although in other cases that may be true, in these situations it is transient roof rats that came and went.

These events cause homeowners and pest professionals alike much frustration in chasing “ghost rats,” which may or may not visit the building again. Unfortunately, in neighborhoods where roof rats have abundant cover and food over several blocks, these events are common but unpredictable. The best strategy for residents in such areas is to rodent-proof their homes and buildings as thoroughly as possible and minimize leaving any attractive resources that may draw rats to the premises (e.g., spilled food, open garbage cans, etc.).

Against a backdrop of critical March 15 presidential primaries, NPMA Legislative Day attendees met with Congressional representatives to raise awareness of three issues impacting them: the Department of Labor’s (DOL) proposed overtime rules; NPDES permits; and the role the industry plays combating Zika virus.

This year’s Legislative Day, lead-sponsored by FMC, was unique because of the circumstances surrounding it. On March 15, five states held both Republican and Democratic primary elections with several hundred delegates up for grabs. Florida and Ohio were considered the two big prizes of the night, as each state awarded all of its delegates to the statewide winner. If Republican frontrunner Donald Trump had captured both Ohio and Florida, he would have secured the approximately 60 percent of delegates needed to officially be the nominee. (As it turned out, Ohio Gov. John Kasich won Ohio, while Trump took Florida, meaning that at press time Trump needs to win roughly 60 percent of the remaining delegates to clinch it.)

PROPOSED OT RULE CHANGES. Why is the presidential election important to PCOs? Take, for example, the centerpiece issue of Legislative Day: The pest control industry’s opposition to the Department of Labor’s proposed overtime rule. The proposed rule would raise the minimum threshold to approximately $50,440 annually ($970 per week) in 2016. The final rule is anticipated to be released in summer 2016. With that timing occurring just before President Obama leaves office, it is an issue that has the potential to become highly politicized.

As background, in summer 2015, DOL proposed new overtime (OT) regulations in response to a 2014 directive by Obama to update OT rules under the federal Fair Labor Standards Act (FLSA). FLSA guarantees overtime pay at a rate of one and one-half the employee’s regular rate of pay for hours worked in excess of 40 in a workweek. The current FLSA has a salary threshold of $23,660 annually ($455 per week), meaning ANY employee making less is eligible for overtime. Employees making more than the $23,660 annual threshold are eligible for overtime unless they fall under a specific industry exemption (teachers, doctors, lawyers) or the “white collar exemption,” which includes executive, administrative, professional, outside sales and computer employees.

The DOL proposed rule would raise the minimum threshold to approximately $50,440 annually ($970 per week) in 2016. This new proposed level is equal to the 40th percentile of weekly earnings for full-time salaried workers. The threshold will be indexed to maintain the salary threshold at the 40th percentile. The DOL estimated that approximately 4.6 million employees that are currently exempt based on the $23,660 threshold, will become eligible for overtime under the $50,440 threshold. The rule does not propose changes to the current exemptions, including the “white collar exemption,” and the duties test used to determine the “white collar exemptions.”

The rule does invite comment on these exemptions specifically, which raises concerns that the exemptions could be changed in the final rule. In September 2015 the public comment period for the DOL proposed rule closed, despite requests to extend the comment period.

NPMA’s position on this proposed rule is that while the pest management industry acknowledges the importance of implementing proper compensation mechanisms to protect employees, the proposed rule will result in pest management companies having to convert from a salary-based model to an hourly model out of necessity. This conversion inhibits employee job flexibility, earning opportunities, career growth and lowers morale, NPMA says.

(Update: On March 17, just two days after Legislative Day, Senators Tim Scott (R-SC) and Lamar Alexander (R-TN) and Representatives Tim Walberg (R-MI) and John Kline (R-MN) introduced the Protecting Workplace Advancement and Opportunity Act, which requires the U.S. Department of Labor to conduct a comprehensive economic analysis on the impact of mandatory overtime expansion to small businesses, nonprofits and public employers before issuing any final rule.)

NPDES PERMITS. Legislative Day attendees also encouraged members of Congress to revisit the newly finalized Clean Water Act (CWA). The original CWA, enacted in 1972, gives EPA the authority to regulate all of the waters of the U.S. (WOTUS), historically defined as “navigable” waters, including interstate waters and territorial seas. On May 27, 2015, EPA and the U.S. Army Corps of Engineers finalized the Clean Water Rule, which expanded the definition “waters of the U.S.” to include “tributaries and waters that significantly affect the chemical, physical or biological integrity of the aforementioned traditional navigable waters.”

The expanded WOTUS definition is not expected to have a significant impact on those who perform structural pest management; however, included in the final rule is language that would maintain the current status quo concerning the National Pollution Discharge Elimination System (NPDES). NPDES is a national permit program that regulates the point source discharge of pollutants and chemicals into waters of the U.S. EPA has delegated NPDES authority to the states; currently 46 of the 50 states regulate NPDES permits independent of EPA. NPMA’s position is that NPDES permits are unnecessary, redundant and a costly burden because pesticides are already reviewed and regulated under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

There are two pieces of legislation NPMA is encouraging its members to support. In the Senate, the Sensible Environmental Protection Act of 2015 (S. 1500) was accepted as an amendment to the Bipartisan Sportsman Act of 2015 (S. 659) which passed the Committee on Environmental and Public Works, and awaits a full Senate vote. In the House, the Reducing Regulatory Burdens Act of 2015 (h. 897) has been recommended by the Committee on Agriculture for a full House vote.

ZIKA VIRUS INVOLVEMENT. The pest control industry also used its Capitol Hill visits to raise awareness of the role the pest management industry plays in combating the Zika virus. Zika is an emerging mosquito-borne virus that currently has no specific medical treatment or vaccine.

NPMA is encouraging legislative and executive action to highlight the important role the pest management industry plays in preventing exposure to mosquitoes. There are 20,000 pest control companies who collectively employ more than 150,000 service technicians. Many are trained to identify and treat for mosquitoes in residential backyards, subdivisions, commercial properties and other public and private settings.

In addition to Capitol Hill visits, Legislative Day included sessions on pesticide issues (e.g., pesticide re-registration and fumigation updates) and business issues (e.g., labor issues). Attendees also were treated to presentations from Washington pundits. For the Monday luncheon, sponsored by FMC, Paul Begala paired off with former White House Press Secretary Ari Fleischer to offer perspectives on the 2016 Presidential campaign. Political analyst Nicolle Wallace reviewed why partisanship can be good, in a speech sponsored by Dow AgroSciences, and political commentator SE Cupp gave her thoughts on the presidential race, in a session sponsored by Control Solutions Inc. MGK hosted the “Headquarters on the Hill” luncheon event at the Rayburn House Office Building, a congressional office building for the U.S. House of Representatives.

The author is Internet editor and managing editor of PCT and can be contacted via email at bharbison@gie.net.