Rodent IPM and Fertility Control as a Preventive Measure

Some rodent control professionals have found that fertility control can enhance preventive measures by helping keep rodent populations to a controllable level.

Two rats can produce hundreds, if not thousands, of offspring in a single year. So, when rats are sighted in or around a business, the first thought is to get rid of them. However, an all-out war on rodents can be counterproductive. A rodent’s immediate response to any threat to its colony is to breed which can lead to a steep population increase, said Missouri Pest Consultants Owner Terry Hoselton. “So, you need to get them to stop breeding.”
Hoselton uses fertility control as a preventive measure in his standard IPM programs. Fertility control is a non-lethal contraceptive that restricts reproductive abilities in male and female rats. When consumed, rat fertility is reduced, thus minimizing the number of juveniles within the rat population. 
“We integrate it into our standard program to get populations under control and prevent population growth,” Hoselton said. It is particularly ideal where rodent populations are high, especially in agriculture settings, packing plants, etc., he said. “Anywhere there is an ongoing problem, fertility control is great,” Hoselton added.
In conjunction with other tools, including sanitation enforcement, education and rodenticides, D.C. Health’s Rodent and Vector Control Division sees fertility control is an important preventive measure. “IPM and preventive control measures, including fertility control, are very important tools in our toolbox to help reduce the rat population in Washington, D.C.,” said Program Manager Gerard Brown. “We use an integrated approach that includes public outreach and education, surveys and inspections, abatement, enforcement, and cooperation with public and private partners.” 
Agrecom Owner Mike Altomare goes even further, seeing fertility control as “a missing link we’ve been needing in rodent control.” Although he just starting integrity fertility control in his program, he has found the results to be very promising, he said. He has used it primarily in poultry facilities.
Using fertility control enhances preventive measures by helping keep populations to a controllable level, he said. “The biggest problem is they reproduce so quickly,” he said. So, like Hoselton, who introduces baits after 30 to 60 days of fertility control, Altomare still uses rodenticides, but that use can be reduced by keeping the populations down. 
The DC Health division initially worked with restaurants and retailers in a pilot in which fertility control was deployed in commercial alleys in restaurant districts, Brown said. And during the COVID-19 pandemic, the division deployed fertility control in more residential areas, “as more people are staying home increasing the amount of residential trash,” he said.
Rats generally come in from the outside, so it is difficult to completely eradicate them. But you can reduce the potential for entry by getting them to consume the fertility bait outside the facility. “It’s a numbers game,” Altomare said. “If you can reduce the reproduction, the pressure will be dramatically less.” Then, if the rodents are not reproducing, its colony will eventually die out.
IPM is critical to rodent control, Altomare said, “And baiting is part of it. So, fertility control is another tool in the IPM program.” He sees fertility control as a real opportunity for the industry “Rodents have the ability to reproduce at an alarming rate,” he said. “You have to get ahead of it, or you’ll be behind the eight ball.”