Implementing a DIY program for Rodent Control

There’s no question that rodent control is a critical aspect of food safety in a food or beverage processing plant.

But what exactly constitutes a good rodent control program?

Can rodent control be effectively—and legally—handled in-house by plant personnel?

To answer these questions, QA spoke with rodent control product manufacturers on implementing a DIY program.

The general answer is: Yes, rodent control can be handled in-house if those responsible have a thorough understanding of rodents, a preventive program is established and maintained, and no current infestation exists.

Additionally, some methods of rodent control do require licensing and/or certification.

Understanding Rodents.

“Rodent control can be particularly challenging because mice and rats are thinking animals, and will change their behavior depending on the situation they encounter, said Syngenta Professional Pest Management Senior Technical Representative ElRay Roper.

Thus, personnel involved in rodent control need to have working knowledge of rodent biology and behavior.

“It’s important that they know what the signs of rodent activity are along with how, when, and where to look for rodent harborage and activity.”

(As a resource, Roper recommended PCT’s Rodent Control; A Practical Guide for Pest Management Professionals by Robert M. Corrigan available at http://store.pctonline.com.)

“Mice and rats are opportunists and will scavenge nearly any kind of food,” said Bell Laboratories Technical Director Troy Ryba.

And with the size of openings that mice or rats can pass through being astoundingly small—less than a dime-sized hole for mice and nickel-sized for rats, those opportunities can be incredibly high. 

Rodent control is not only about eliminating rodents, it also is important to address conditions conducive to an infestation quickly and safely, added J.T. Eaton National Marketing Manager and Associate Certified Entomologist James Rodriguez.

“This requires knowing the rodents common to the geographic region, their abilities and biology, and some practical knowledge of construction to seal rodents out of the building.”

A few of the capabilities rodents have for entering buildings were cited by GMT Director of Marketing Drew McFadden: Rodents can chew through door sweeps and seals, dock levelers, and any foam or caulk sealants; they can run along electrical wires, ropes, cables, vines, shrubs, and trees to gain entry to a building; they can climb rough vertical surfaces or crawl along pipes, augers, conveyors, and conduits.

“Even a facility with sound exclusion practices can still be vulnerable to invasion by mice or rats stowing away on inbound shipments,” McFadden said.

Because of this, “the best offense is a good defense,” said VM Products Independent Sales Representative Vicki Holst.

And, in rodent control, as in all aspects of food safety, prevention is the key. This is also apparent in the upcoming regulations of the Food Safety Modernization Act (FSMA), in which there will be a much higher scrutiny of pest control programs, she said.

A Preventive Program.

“When considering whether or not it makes sense to handle rodent control in-house, it is important to consider whether you are just performing regular maintenance for rodent prevention or trying to handle an active rodent infestation,” Roper said.

And rodent control is not simply refilling bait stations or setting out some traps.

“To be effective, a rodent control program must look at the environment of the plant, including outside sources of rodents,” he said.

“Prevention is the key and requires support of plant management and personnel.”

For virtually all pests, access, food, water and harborage are the main attractions, said Pest Barrier by Bird Barrier Technical Specialist Jeff McGovern.

“Dealing with these four items will pressure the pest population into nonexistence in any facility. In simple terms, the pest must be denied a way in, water, food, and a place to live.”

This is achieved through cleaning, sanitation, maintenance, and product rotation.

“The plant must be a place where pest resources are simply nonexistent or kept to a bare minimum,”
McGovern said.

This is not always easy, so regular assessment and evaluation of the plant are necessary to ensure pest resources are not developing. If they are found, immediate action and follow-up will ensure that the facility is rodent-free.

Additionally, he said, “To prevent a new generation, employ rodent-repellent products to make the structure so unattractive that penetration will be held to almost zero.”

Good housekeeping of the interior and exterior to remove food sources is one of the best, most cost-effective long-term rodent controls, Ryba said.

“If there is nothing to eat, there will be little reason to stay for long. Even simple, but frequent cleanups will go a long way toward mitigating a rodent infestation.”

Rodent Elimination.
It is generally recommended that a professional be contacted if the plant’s program reveals a rodent infestation.

“Once an infestation is identified, the real work begins. The best choice is to employ the services of a pest management professional who is experienced in rodent control,” Roper said.

“The knowledge and tools needed to eliminate an active infestation are much more extensive than those needed to maintain a facility that is rodent-free.”

But whether or not the program is outsourced, if an infestation is detected, a first step is identifying how the rodents are getting in to your facility, McFadden said.

Is your building structurally sound?

Is there concrete shifting or gaps around garage doors?

Are the dumpsters unprotected?

Implementing exclusion techniques, consistently inspecting exclusion work, and being religious about sanitation should all be aspects of your rodent program.

Employee practices also are critical in both rodent prevention and elimination. Employees need to ensure that doors are closed, break-room areas are clean, and all food sources are kept off floors, Ryba said.

Liphatech Technical Support Manager Ted Bruesch cites six key elements of effective rodent infestation elimination as including:

1. Know the rodent. Acquire a good knowledge of rodents, their behaviors, and control options, including the strengths and weaknesses of sanitation, exclusion, traps, and rodenticides. 
2. Perform a thorough inspection. Use a ladder and flashlight—rats and mice will travel much farther than what “the book says” if they need to. 
3. Choose the control method. You may be able to stress a colony enough through sanitation and exclusion to cause it to relocate. Professional application of rodenticides may be the most cost effective, but traps provide carcass containment. 
4. Put control materials in the proper place. Do not expect rodents to deviate from established runways they know to be safe. Use materials such as Velcro, tie wraps, double-sided tape, nails, screws, and putty to get control materials in their path. 
5. Use enough material. Full traps or empty bait stations can indicate an infestation which can out-breed the control program. If needed, use larger devices, install more devices, or service them more often. 
6. Manage the risks. Doing nothing carries risks of damage and disease. Traps carry risks of not eliminating the rodents fast enough to crash the population. Rodenticides carry risks related to their active ingredient and the potential for dead rodent odors.

“All food plants should have an active monitoring program that enables them to continuously collect and record information on pest activity,” Holst said.

It is very important that a person is responsible for managing rodent control, and that a backup is assigned.

Pest management requires a large investment of time and money in education, tools, and time. Thus, she said, “In situations where the majority of the work is inspection, some facilities do the inspections on their own and contract with a pest management company when activity is found in an effort to reduce costs.”

Trap Placement.

Traps are one of the most basic and essential of rodent control tools, and the inspection and maintenance of traps is a common practice of in-house rodent management.

“It doesn’t require a license or special skills to use monitoring blocks (rodent blocks with no poison) or some type of solid food that’s somewhat weather resistant in rodent bait stations around the border of the property and inspecting at regular intervals,” Rodriguez said.

This will give you your fist indication when rodents are present. Every plant is different, but monitoring trap activity can help determine the spacing needed for traps and enable plant personnel to analyze where other prevention methods should be placed, said Gremar Vice President Claudia Hoskins.

Roper provided the following tips for trapping:

1. Exterior. Always trap in bait stations. For mice, consider baiting with nesting materials such as string, cotton balls and cloth. 
2. Interior. Trap in a place where rodents are most likely to be active. Use more traps than you think you will need. It may be necessary to set several traps together. Pre-baiting on unset traps is important if you actually have an infestation.
3. Placement. Trap spacing is not as important as location. Putting traps where rodents never go is a waste of time and money. Put more traps in shadowy, quiet, undisturbed areas where rodents are likely to travel.

“It will be time well spent to locate ‘hot spots’ of activity—areas that have evidence of rodent activity (gnawing, fecal matter, etc),” Ryba said.

From this analysis, best placement sites can be determined.

“Equipment should be installed where inspections have determined rodent susceptibility and/or activity to exist,” Holst said.

Then ongoing inspection is important to determine if equipment needs to be added or moved. To maintain consistent protection against rodents, it is important to leave the pest control devices in place, Ryba said, adding that company employees need to be mindful of rodent control equipment during daily business.

For example, if the floor is being hosed down, ensure this does not disturb the rodent equipment. Site logs help ensure that rodent control devices are placed—and remain—in the proper location

Plant personnel need to be aware of local laws and regulations in regard to rodent control, McGovern said.

“For example, what are the approved toxicants or trapping methods to deal with rodent issues?

In some cases, there may be additional internal corporate requirements that need to be followed.” 

Licensing and Certification.

“Most rodent control does not involve applying pesticides, so there are few, if any, restrictions on who can perform this work,” Roper said.

However, if an employee is applying rodent bait, he or she should be licensed by the state as a pesticide applicator.

There are also other issues to consider such as insurance, storage, transportation, and regulatory compliance.

Regardless of whether the program is in-house or outsourced, rodent baits should not be used by an untrained, unlicensed individual, Rodriguez said.

Not only are there very specific regulations for pesticides of any type in and around food facilities, but a rodent that consumes a rodenticide may die in a wall void—creating an odor and attracting secondary pests, or outdoors—posing the risk of residual poisoning to non-target animals.

Continual Surveillance.

“Rodents have survived for millennia because they are smart and react to changes in their surrounding environment,” Roper said.

Effective rodent control requires use of all the skills you have, starting with thorough inspections, sanitation, and exclusion.

In addition, changes may have to be made to plant practices in order to minimize conducive conditions that would encourage rodent activity around the plant.

The author is Editor of QA magazine. She can be reached at llupo@gie.net.