[Annual Rodent Control Issue] Dealing With Elusive Rodents

Quite often people I meet ask me, “What’s a good product to kill rats or mice”?

I enjoy answering this question because I use it as an opportunity to educate customers about effective rodent control. Normally when these sorts of questions are raised, it’s not just small talk — chances are they are experiencing some pest problems. Most of the time at the end of our discussion they will acknowledge that effective rodent control is not only about the product but the expertise and skill of the applicator as well.

The skill of the applicator is especially important when dealing with rodent pests like Norway rats. Norway rats are known for being incredibly cautious and secretive. When dealing with any rat infestation, the rats’ behavioral characteristics must be considered if you want to be successful. Here are some things to keep in mind when approaching a difficult rat job:

Customer cooperation. With a rat infestation, the PMP needs to have an honest and realistic discussion with the decision maker (i.e., the property manager or owner). Certain rodent problems cannot be resolved overnight. In fact, in some cases, it can take weeks or months to get results. This is particularly true when there is an elusive rat. Most experienced applicators have dealt with such a rat at least once in their careers. This situation has the potential to frustrate any veteran within the industry, although at times, the situation can be rewarding.

To increase your chances of being successful and controlling most rodent infestations, you need to find out as much information as possible about the account. For commercial accounts, logbooks provide valuable information on current and previous rodent complaints. They also should mention what corrective action was taken and list conditions conducive to the pest infestations. Get feedback from the employees to determine the possible source of the problem. There may be conflicting opinions but if you ask enough people, a pattern will soon develop that will lead to one or more sources.

The New York City Department of Health has a pest control database that documents the locations of rodent activity complaints. Perhaps your city or state has something similar. If so, you can use this to find out if there are any surrounding areas that may be affecting the account.

Armed with whatever information that can be acquired, a wise applicator will analyze the situation to determine what may have contributed to the problem. Also, you may have a clearer picture of what part of the structure has the most rodent pressure (e.g., east, west).

When these steps are ignored or overlooked, the control program may not be successful. According to rodent expert Dr. Bobby Corrigan, this can lead to:

1. Underestimating the size and scope of infestations;
2. Under baiting rat burrow systems;
3. Installing bait boxes in a “yardstick” measurement instead of installing equipment based on inspecting to pinpoint the high- activity areas.

Addressing a Norway rat issue effectively will require time and this should be emphasized to the customer. On many occasions the client may force the technician with a “get it done now or you’ll lose the account” attitude. This puts technicians in a touchy situation where they will have to sympathize with the customer and patiently explain that when dealing with a rat, the time factor is crucial.

Snap Trap Tips. In line with this thought, one of our company’s former entomologist used to say that PMPs may get pressured to rush control measures and by doing this they may prolong the time it takes to trap the rodent.

In attending rodent control seminars and reading books over the years, one statement is often repeated: Leave snap traps unset for a couple of days before setting them. This is done because rats are cautious of new objects and the rodent will need time to get accustomed to these devices. If this process is not followed and a cautious rat stumbles upon a newly set trap and experiences a “near miss,” that rat now becomes conditioned to stay away from similar traps. Such a rodent becomes difficult to catch. That gives rise to a “rogue” or “elusive” rat. When this happens you may have to be creative in your trapping technique. So in addition to prebaiting the snap traps, you may have to disguise the device.

Challenging rodent jobs may require the use of non-traditional equipment to assist in the trapping process. Infrared cameras and borescopes have proven to be helpful. For example, a few months ago at a commercial kitchen, the client had a “phantom” rat that was seen only by the customer. Personnel from the pest control firm would inspect but find no droppings, rub marks or damage, which was puzzling. Eventually with a team effort and some consultation from two entomologists, the pest control team was able to use a borescope with video capabilities to pinpoint where the rat was hiding. Shortly after this they were able to effectively trap the rat. This job took at least two weeks to complete. But all who were involved with this challenging assignment learned a valuable lesson. Since the Norway rat is cautious and skilled at avoiding traps, it is only logical that the trapper should possess similar qualities. They saw that perhaps prematurely setting traps may have contributed to the rat’s behavior and that one cannot rush this sort of job.

I’ve learned from that situation that you should not be hesitant to ask for help on tough jobs. During the inspection process a second or third individual can pick up on something that you may have overlooked.

When it comes to dealing with a difficult rodent, you need to understand the history of the account by gathering as much information as possible. Customer cooperation is needed.

The author is an Associate Certified Entomologist with Assured Environments in New York City. E-mail him at carcher@giemedia.com.