Zeroing In On Rodents

Pest management professionals experimenting with non-toxic bait blocks have crossed a new threshold in rodent integrated pest management (IPM) strategies. Better monitoring of rodent populations with the non-toxic baits helps professionals identify rodent infestations and estimate their severity, allowing PCOs to choose and target the most effective control measures.

By using rodenticides only where monitoring indicates they are needed, PCOs can reduce waste, disposal hassles and the potential liabilities that might be incurred as a result of unnecessary rodenticide baiting. And by using traps and glueboards only where needed, they can reduce labor expense, theft and disturbance.

When non-toxic bait blocks are used in conjunction with rodenticides or traps, they can serve as a check on the effectiveness of those control methods.

IPM has kicked up controversy in the pest control industry, particularly in the household insect control market (see "IPM: A House Of Cards?" in PCT's June 1995 issue). But rodent control especially in public or industrial settings lends itself well to integrated pest management.

Pest management professionals can use signs of feeding on non-toxic bait blocks along with familiar clues like droppings, tracks, and other gnawing damage to ascertain whether there is an infestation, what species is involved, and where the population feeds and travels. Based on those conclusions, PCOs can develop a targeted program of sanitation, exclusion and control designed specifically for the situation at hand. After initial knockdown and control of the infestation, PCOs can return to the use of non-toxic bait blocks to ensure that the job was done correctly and to serve as an early warning if another problem develops.

Purdue University rodent control specialist Robert M. Corrigan notes that monitoring programs are especially important in the many places where pest management professionals would rather not place rodenticides until they are sure there is a need for them. For instance, he predicts that monitoring with non-toxic baits "will be an excellent IPM tool in programs at schools, zoos, and in the food industry."

BAITED IN BOSTON. Non-toxic bait block monitoring tactics have been put up against the major rodent control needs spurred by Boston's enormous 10-year Central Artery/Tunnel Project. Demolition, digging and building in the city have created significant pest control challenges as PCOs and project biologists have successfully worked to prevent rats and mice from relocating from work zones into adjacent buildings and public spaces.

Todd Bullen, head pest control technician for Envirsan of Somerville, Mass., a pest control company working on the Central Artery/Tunnel Project, used non-toxic bait blocks to monitor rodent activity in a park used daily by a local day care center. The non-toxic blocks replaced stations baited with rodenticide, which had to be checked for feeding and maintained daily. The switch to non-toxic baits helped Bullen and the day care providers breathe easier, and reduced time and expense for Envirsan.

"For some rodent placements in the park, we had to remove the bait every day and put it back at night," he explains. "With the non-toxic bait, we can leave it out and just monitor it every few days."

According to Dr. Bruce Colvin, senior scientist for Boston's Bechtel/Parsons Brinckerhoff, non-toxic baits allow PCOs to efficiently monitor a huge area affected by the Boston project without managing large numbers of bait stations.

"In the Central Artery Project, the use of non-toxic baits has enabled us to conduct large-scale and highly effective rodent surveillance," Colvin says.

"An advantage of non-toxic bait blocks is that they don't have to be placed in bait stations," he explains. "They can be wired to bushes or fences. Non-toxic baits can be easily used to establish a greater number of monitoring points compared to rodenticide baits. And because they do not have to be monitored as closely as rodenticide baits, they also allow PCOs to check them when time allows."

Like Corrigan at Purdue, Bullen and Colvin used Census Bait Blocks from Zeneca Professional Products in their IPM programs. The blocks are the same size and shape as Zeneca's Talon Weatherbloks. However, the non-toxic Census blocks do not contain the bittering agent Bitrex, which is added to Weatherbloks to discourage accidental human ingestion; nor do they feature a skull-and-crossbones warning symbol. As a result, PCOs and medical professionals can determine immediately whether a question about accidental exposure involves a non-toxic bait or a rodenticide formulation.

In addition, the Census blocks are brown instead of the blue of Talon Weatherbloks, which makes them easy for PCOs to differentiate in the field, and makes blocks wired to fences or bushes less noticeable to children and pets.

MANAGING CUSTOMER RELATIONS. An IPM program using non-toxic bait blocks can be a valuable customer relations tool, according to the pest management professionals who have used them.

Many customers now demand IPM-style programs and reductions in the amount of rodenticides and insecticides used on their properties. Even many homeowners are abandoning the shoot-first-ask-questions-later approach of yesterday's pest control strategies, especially for outdoor pest management.

Austin Frishman, president of AMF Pest Management Services in Farmingdale, N.Y., is recommending that a local PCO client use Census blocks for rodent monitoring around some estates along Long Island's posh North Shore.

"Residents often object to a rodenticide being put out unless they are sure there is a problem," he points out. By monitoring rodent activity around the property with non-toxic bait blocks, Frishman's client can first provide homeowners with evidence of a problem, then target specific areas for rodenticide baiting. In the process, he can meet his customers' wishes of reducing overall rodenticide use.

Richard Berman, technical manager for Waltham Chemical Company, Waltham, Mass., sees promise for non-toxic bait monitoring in public areas and highly controlled industrial environments.

"We have used Census blocks, and find the concept very appealing," Berman says. "In one instance, we were able to monitor a rodent burrow that appeared at the edge of a public walkway, where we didn't want to use a rodenticide bait because of safety concerns. I also see a market for non-toxic baits in high-tech fields that demand a sterile environment."

Nothing is more important to customer satisfaction than a job done correctly. PCOs can use the non-toxic baits as part of their own quality control and ongoing monitoring efforts. Because the rodenticide-free blocks do not require a license for handling, PCOs who enjoy strong working relationships with their customers can also get building superintendents more involved in the pest control process by having them place and check the non-toxic blocks. So in addition to teaming up on sanitation and exclusion procedures, pest management professionals and their key clients can now collaborate on infestation monitoring and IPM implementation.

As always, the success of IPM as a customer relations tool requires a customer who knows enough to appreciate the process and its benefits.

"A PCO will first have to educate their customers on the value of using a non-toxic bait to detect and monitor rodent activity," notes Dr. Mark Wisniewski, training and safety director for Presto-X-Company of Omaha, Neb.

NOT APPROPRIATE EVERYWHERE. Although non-toxic bait blocks have a wide variety of uses, they are not suited for every rodent control situation, notes Zeneca Professional Products technical lead Dale Kaukeinen. Where adequate signs and previous experience indicate rodents are already present, and quick and complete cleanout is required, applicators should move directly to the use of control materials.

Situations where rodents present an imminent public health hazard, such as the spread of disease, also may demand more intensive initial application of control materials. Less time may be available to detect and monitor.

But for many rodent control situations, non-toxic bait blocks will give pest management professionals a great deal of valuable information that will lead to more effective control.

PCOs need to be willing to commit the time to place and monitor the blocks rather than simply put rodenticides in the most likely feeding sites and hope for the best. And customers need to understand that they are participating in a scientific IPM process that may lead to a delay in treatment in order to more precisely locate and more effectively control the population later.

Kaukeinen says he is confident that the industry and its customers will embrace this new tool in integrated pest management. And as pest management professionals adopt tools like Census blocks to help improve and promote IPM practices, the pest control industry will continue to show its scientific and environmental commitment to a more vigilant public.

As Austin Frishman notes, "Census blocks are a little ahead of their time but that is where you have to be."

Dale Kaukeinen serves as technical lead for Zeneca Professional Products, Wilmington, Del.

Census Blocks: A Quiet Revolution

It is ironic that one of the most exciting rodent IPM tools of the year contains no rodenticide at all. It also speaks highly for the structural pest control industry that integrated pest management techniques are becoming increasingly adopted. Progressive pest management professionals are fostering a strong movement toward IPM and monitor-before-treating pest management systems. Pest control focus groups sponsored by Zeneca Professional Products have verified the trends in rodent control that are underway. Shifts toward increased monitoring and increased use of bait blocks appear especially pronounced. Zeneca is proud to introduce and promote Census Bait Blocks as a tool for integrated pest management programs. The product will allow PCOs to make better, more well-informed pest control decisions, use rodenticides and traps with greater precision and effectiveness, and continue to demonstrate the environmental consciousness and responsibility of the structural pest control industry. Census Bait Blocks can also serve to improve bait acceptance by rodents that grow accustomed to feeding on the non-toxic bait before Talon Weatherbloks are introduced. In addition, Census blocks make excellent bait for glueboards, traps and rodenticide bait stations. As pest management professionals develop and modify their IPM programs, they will undoubtedly find new and exciting ways to use Census Bait Blocks and other tools of the trade. We hope Census will serve as a tool for the forward-thinking PCO to broaden his or her IPM programs, build better customer relations, and improve the image of the pest control industry. Zeneca does not expect Census Bait Blocks to take the pest control business by storm as Talon did when we introduced it in 1978. Instead, Census represents a more subtle revolution in rodent control: a significant step toward better, more effective, more environmentally friendly IPM systems. Dale Kaukeinen