Here in Georgia, there are two species of rats that get into buildings.
The Norway rat (Rattus norvegicus) is more common in urban areas, but is occasionally found in the country. Norway rats are stocky rats who are burrowers by nature. They're sometimes called "wharf rats," "brown rats," or "sewer rats," and are the most common rats found in cities. They're excellent swimmers and are, in fact, able to swim through sewer pipes and emerge through the toilet, as this video shows.
Norway rats are more commonly found in basements, crawl spaces, and in burrows outside buildings. Although they can easily climb to higher floors and sometimes do so when population pressures force them to, they're more commonly found on the lower levels of buildings.
Roof rats (Rattus rattus), also called "black rats," are lighter and sleeker than Norway rats, being tree-dwellers by nature. They're slightly more common in rural areas than in urban ones. Unlike Norway rats, roof rats are aerialists and prefer high places. They're usually found in attics, bell towers of churches, drop ceilings, roof soffits, and other elevated spaces.
Roof rats are also very common in barns, grain elevators, and other areas where seeds or grain are stored or processed. They have excellent balance and are able to run along power lines to get into buildings. Their habits are actually closer to those of gray squirrels than they are to those of Norway rats.
Both Norway rats and roof rats are gnawers by nature, and both species get into buildings by gnawing and scratching their way in. They can gnaw through most building materials, but usually choose the easiest path into a building. They are especially likely to seize upon a small, existing gap or hole and gnaw at it until it's big enough for them to fit through comfortably.
On occasion, a building can be infested by both species of rats, but they do not get along well. Norway rats are the stronger and more territorial of the two species, and they will kill roof rats that invade their territory and refuse to leave. When the two species do coexist, it's usually in a large building where the roof rats infest the upper spaces and the Norway rats the lower ones. The two species cannot interbreed.
Rats have a special place in the history of pest control because as far as we know, they were the first animals that were so despised that people were willing to pay other people to kill them. The profession of pest control began with men who called themselves "rat catchers," and who made their livings catching and killing rats.
Many people also consider the rat catchers to be the first public health professionals. Doctors fought diseases afflicting individuals, but rat catchers were the first professionals who worked full-time to prevent the spread of disease throughout entire communities.
The public hatred of rats that was so intense as to inspire people to pay rat catchers to kill them was not without good cause. Rats have been associated with disease since at least biblical times, and possibly even earlier. People back then didn't have the scientific knowledge to understand the mechanisms by which rats spread disease, but they did notice that high rat populations were associated with more people getting sick.
Today, with the benefit of science, we know that rats are involved in the transmission of serious diseases like bubonic plague, hantavirus, hemorrhagic fever, rat-bite fever, salmonella, and many others; and today's "rat catchers" are just as much public health professionals as were the founders of the pest control profession. We're proud to follow in their footsteps.
Rid-A-Critter is also proud to be one of the few companies that completes most structural rat control jobs completely non-chemically. Some consider this a revolutionary approach, but it's really the old-school way of doing things. Early rat catchers used mainly non-chemical methods. Poisons did exist back then, but because the science was crude, someone using poisons to kill rats stood a chance of killing himself in the process. So early rat catchers controlled rats pretty much the same way Rid-A-Critter does today: They trapped them, removed them, and sealed them out of the building.
There are many reasons why we don't usually use poisons to kill rats. For example:
Rodenticides are poisons. The problem is that they're not rat-specific. Most of them work by modes of action that can also kill non-target animals. Worse yet, some of them are toxic enough that animals that eat the poisoned rats may also be poisoned and die. This is known as "secondary toxicity."
Rats that die in your home stink. Animals are a lot like people in some ways, and one of them is that when they feel sick, they stay home from work. Because most rodenticides are slow-acting, poisoned rats start to feel sick before they die. When this happens, they don't go out to feed like they usually would. They call in sick and stay home. And most of the time, that's where they die. When that happens, finding and removing the dead rat can be very difficult. But until you do, your house will stink so badly that it will be virtually unhabitable.
In fact, we have a pretty good side gig going just removing dead rats (and other animals) that were killed by the poisons that other less-enlightened rat exterminators tossed around in people's houses. That's another reason we don't like using rat poisons.
Poisoning rats is a band-aid approach to the problem. It really makes no sense at all to kill the rats inside a building if you're not going to seal up the building so new rats can't get in to replace the old ones. Conversely, if you do seal up the home or building against rats, then there's no need to use poisons. Trapping works better and eliminates the possibility of a rat dying inside a wall somewhere and stinking up the place.
In a word, rarely. Sometimes they're useful in area-wide, community rat control programs, such as when a sewer system is badly infested with rats. Dead rat odors in a sewer aren't that big a deal, comparatively speaking. Rodenticides in tamper-resistant bait stations may also be required by local codes or industry standards around the exteriors of some buildings, such as food-processing or food-storage facilities. Also, municipal health departments sometimes require buildings that are being demolished to be treated with rodenticides to assure that any rats in the buildings are not displaced. This is commonly called obtaining a "rat clearance letter."
But there is almost never any reason to use rat poisons inside a building, unless it's being demolished. It's simply not necessary. If the building is properly rat-proofed, there's no need, no justification, and no up side to using rat poisons. They serve no purpose. A non-chemical, exclusion-based IPM approach is better in every way.
At Rid-A-Critter, we specialize in safe, long-lasting, non-chemical rat removal and rat-proofing. We also clean up after the rats, sanitize as necessary, and even remove and replace contaminated insulation if needed. Please contact us for more information about our rat-extermination services.
Rat Control Gallery
Here are some pictures we've taken at some of the rat-removal jobs we've done in the Augusta area.
Rat damage to interior trim of an Augusta home
Rat droppings and acorn shells in a crawl space
Technician using fiber-optic scope to find rats
Rat hole in a house in Augusta
Rat entry through the soffit at a house in Augusta
Rat droppings in a kitchen drawer in Augusta
Roof rat droppings at an Augusta rat control job
Rat hole on exterior wall of a house in Augusta
Roof rat entry hole in an Augusta, Georgia home
Rat entry hole through A/C in Evans, Georgia
Rat entry into the foundation of an Augusta home
Rat hole in a crawl space door in Augusta
Rat entry hole into a house in Augusta
Rat rub marks found at an attic rat control job
Roof rat entry hole in a house in Augusta
Rat damage to wires in an attic in Augusta
Duct-tape rat-proofing attempt in Hephzibah
Do-it-yourself rat control didn't quite work out
Rat hole in a roof exhaust fan screen in Augusta
Missing brick allowed rats into an Augusta home
Roof rat hole under the shingles in Augusta
How NOT to seal rats out of your home
Rat control in a basement in Augusta
Rat droppings in snack bar of an athletic field