E2M2C: To Assay, or Not To Assay… A Difficult Question of Great Importance

This article by Jerry Cates, first published on 11 June 2021, was last revised on 29 December 2022. © Bugsinthenews Vol. 23:06(01).:

Click Here for: Important Notice about the E2M2C™ trademark , the Ownership, Placement & Servicing of E2M2C™ Devices, and Program Participation/Termination

In the original posting of this article, I explained why, back in June of 2021, we temporarily halted our assays of the E2M2C™ devices involved with rodent control, during servicing of those devices in our lab. The reasoning behind that hiatus was and is unassailable. However, we know all too well that those assays provided essential information needed for our on-going research, as well as for informing our clients about the nature of the rodent activity at their sites. Without that information, our research and development programs suffered, and our participating clients were left in the dark.

The E2M2C™ program works wonders, but the costs are not trivial. Participating clients need to know if the E2M2C™ program, as originally configured, is still needed for their sites. Once those previous rodent issues get resolved and all those earlier rodents are history, why keep the program going? If new rodent arrivals don’t appear to be showing up, continued participation in the program could be a waste. Even with fresh evidence of new rodents, that doesn’t mean the program can’t still be adjusted downward.  An analysis of the amount of rodent activity at the client’s site — over time, in each device — that shows where the device was when that activity took place, would answer those questions. Although our clients understood why we paused the assays, they still needed to know if the program was still needed, and if so, if it required the same number of devices. Here are some of the questions we’ve been asked since that day in June of 2021:

“Do we still need the E2M2C™ program, or have the rodent issues that prompted us to enroll in the E2M2C™ program already been solved for good?

“If the program is still needed because fresh rodents keep arriving from surrounding areas, do we really need all those devices, or — assuming the number of rodents now visiting our site had diminished — could we now get by with less?”

“What about the service interval? Can it be extended beyond the standard once-every-four-months service schedule, to reduce our servicing fees?”

Good questions, all deserving of good answers. Let’s look at each of these questions separately.

It is possible that once existing rodent issues have been resolved, the E2M2C™ program can be safely discontinued. In locales where rodents are epidemic (no rats or mice nearby) rather than endemic (some or a lot of rats/mice nearby) the program may not need to be in force until a wandering rat or mouse shows up. Our assays alert us to this kind of situation when, during a given service interval, zero rodenticide consumption occurs in the devices placed at that site.  

But what are the odds that a home or business, once infested with rats or mice, can ever be considered “cured” of them?Answering that question is one of the most important functions of the E2M2C™ assay. As long as rodents keep consuming the rodenticide stores in the E2M2C™ devices placed at the site, the “cure” has not happened. But zero consumption over two or more service intervals is strong evidence of a remission, at the very least, and perhaps even of an outright cure.  We’ve continued to study all the scientific papers we can get our hands on that deal with commensal rodent biology. We’ve also kept up-to-date on technological advances in rodent monitoring and control within the pest management industry. What we’re learning is three-fold.

First, almost none of the conclusions offered by the extant literature — including those gleaned from the most recent papers published here and abroad — correlate well with our observations in the field. Wondering why, we examined the investigative methods used to reach those conclusions. In practically every case the investigators failed to collect truly objective data based on the real-world conditions. Although praised for the reams of data those studies collected, little of that data was empirical. Instead, most emanated from face-to-face interviews with home and business owners, and cursory inspections for evidence of nests and fecal pellets. In our experience, while interviews and inspections are a necessary first step in any rodent control program, they paint an amazingly incomplete — and often inaccurate — picture of rodent-related activity. In fact, we have learned that only by carefully monitoring nutrient pilferage, by the rodents that visit a given locale over time, can an accurate picture of rodent prevalence and abundance emerge.

Second, few of the objective investigations into rodent behavior, conducted by trained observers, utilized wild rats and mice in their native habitats. Instead, laboratory rats and mice, in laboratory settings, served as models. The behavior of those rodents, living within simulated environments under laboratory conditions, cannot be correlated with the behavior of their wild rat and mouse cousins. Any attempt to do so will produce untrustworthy results. 

Third, although new technologies are being added to the latest rodent management stations being placed on the market, and hawked as advances in rodent monitoring and control, the underlying technologies involved suffer from a myriad of defects. Some of the deficiencies we’ve found will likely be corrected as the technologies mature, but others — a few of which are of crucial importance to the data collection paradigm — appear fatally flawed.

Adding specialized sensor technology to existing rodenticide dispensing and/or euthanizing stations is so costly that basic design defects in the station itself are ignored or overlooked. We’ve identified a number of significant design defects affecting not only the rodenticide dispensers & euthanizing stations presently on the market, but affecting the way those stations are serviced as well. The defects we’ve uncovered keep many rodents from going into them, and for those that do, the same defects prevent many that go in from taking the baits or triggering the euthanizing devices the stations contain. 

Not only that, but non-target animals, including humans and their companion pets, frequent the spaces where these technologically advanced stations are positioned and manipulate them in ways that trigger the stations’ sensors.  Such triggers are indistinguishable from the ones produced by rodents. This nullifies any virtue the technology might otherwise bring to the table.

E2M2C™ solves that challenge, not only by using specially designed, defect-free devices that all rodents find inviting, inside and out, but with a unique servicing protocol that takes the monitoring task to the laboratory, where — instead of relying on crude electronic triggers — specially trained analysts record trustworthy, objective, irrefutable observations.

While incidental to their primary purpose (rodent control) our E2M2C™  devices are designed and serviced in a way that allows them to  perform as excellent monitors of wild rodent activity. By assaying those devices every time they are serviced, we are able to collect data on everything a scientific study needs to to keep track of rodent activity. The E2M2C™ program is now in place all over Texas. Done right, assays of its devices should provide excellent insight into rodent prevalence and abundance wherever the E2M2C™ program is in operation.

We’ve constantly improved the sanitization protocols at our lab since the Covid 19 pandemic hit. Today we feel confident our resumption of assaying our E2M2C™ devices can be done without exposing our laboratory personnel to untoward risks. We’re conducting a limited amount of assays now, and perfecting the assay protocols to ensure the right information is collected and properly interpreted. 


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