Black (roof) rats live near the human settlements. They are excellent tree climbers. They may easily get into buildings via the open windows, roof and upper levels of buildings. If you start hearing strange scratching and gnawing sound in the attic or inside the walls at night, observing black rat droppings pointed on both ends, small tracks and tail trails along baseboards, and smelling a “rodent musky scent” at home, you are definitely to have an indoor infestation. The best option in this case is to kill roof rats with or without professional rat control help.
Common ways of keeping black rats away from homes
The rule number one for the black (roof) rat control is to store food in tightly closed containers and to keep home clean. No shelter and meal means no problems with rodent infestations.
In fact, the roof rats are critters that can be easily repelled by unpleasant sounds and scaring scents. They avoid areas with intense smells of ammonia, essential oils (cinnamon,citric acid, cedar, lemongrass, peppermint, rosemary, mint, tansy), walnut leaves, urinal cakes, toilet bowl cakes, cat litter and urine, burnt wool and liquid smoke.
Thus, you may place cotton balls or clothes soaked in liquid smoke, essential oil or ammonia in the infested areas including attics, false ceilings, wall cavities and voids. Moreover, sprinkle a bit of liquid along their run-paths.
Simply burn a woolen cloth or heer. Then, place the pieces of burnt wool in the attic. The roof rats won’t nest as the smell of burning is a scaring signal of alert.
Sound emitted via using ultrasonic repelling aids or playing rock music are able to deter roof rats at least in the first instance.
Find more information how to protect your home and keep the black (roof) rats away from your attic and belongings here.
How to exterminate severe infestations of black rats
If you have a really bad rat infestation inside the walls and in the attic, livestock farms, store houses, barns and trees in your backyard, the best way to kill roof rats is to seek professional pest control help. The balck rats breed fast and cause a significant damage to human belongings, structural materials and provision.
Professional rat exterminators use leading rodenticides against the critters. They apply chemical fumigation and spraying for the fast and effective killing of roof rats in the less accessible areas. At first, they will determine the rat control strategy for your property and give advice how to make your home unattractive to rodents. Beside, they will treat your home without risk to people and non-target animals.
How to kill roof rats without professional help
There are special rat control strategies how to get rid of a visiting black rat or small indoor infestation. First, start from tidying the attic, pluging holes and cracks, repairing screens, pipes, and air vents to stop the roof rats from entering your home.
Second, you can use various traps to kill roof rats. It is necessary to allure rodents to the trapping mechanisms. Simply leave some meal on the traps in resting position a couple of days. Then, set cage traps, snap traps, steel traps or humane glue traps and place them in the highly infested areas, in the attic. Be cautious to prevent kids and pets from getting into the traps.
Tiles with rodent glue commonly catch little rats. The worst of the sticky traps is that you will have to deal with a half dead rodent! Spring-loaded and steel traps left in the attic are highly effective against a few mature black rats. A high voltage electronic rat killer is a clean, reliable, fast-acting, non-chemical way of black rat extermination.
Third, you can purchase toxic baits and natural corn gluten rodenticides as well. Diphacinone, bromadiolone, brodifacoum, bromethalin, difethialone and corn gluten will kill roof rats in several days after ingestion. Anticoagulants will make the poor critters crawl out from their nests and shelters in order to breathe.
However, they will simply die in outdoor conditions. Moreover, the toxic baits will dehydrate rats, so they mummify fast after the death. Thus, there will be no disgusting smell from the corpses left in inaccessible areas. The drawbacks of this method are that the roof rats may become anticoagulant resistant and that the baits may be fed by non-target animals or children.
Bio baits with Salmonella
The most effective strategy to kill roof rats is to apply biological baits. Typically the rat-specific pathogen in bio rodenticides is bacteria Salmonella enteritidis. 98% population of rat colonies simply dies out from epizootic. In fact, this strategy is eco friendly, harmless to pets, animals, plants and people.
Medication and diy baits
Instead, some homeowners use homemade baits with stab, cutting and settable substances including steel wool, crashed glass, metal wool, stucco, cement and asbestos. You may cook scrambled eggs (or omelette) with sausages and crashed glass or metal chips, or fry bottle corks in butter.
Vitamin D3 oil to kill roof rats
Some homeowners in the USA use the Vitamin D3 5000IU capsules to kill roof rats and their close relatives Norway rats as well. Do not apply Vitamin D2, as it is too weak for this purpose. They drop the Vitamine D3 oil into a dog kibble using a syringe. Put one drop per each kibble and wait 5-10 minutes until absorbed. Then, add another drop. At last, place this toxic kibble on pieces of cardboard or plastic plates/ tops in the most rat infested areas (in attics, garages, cellars and basements).
The Vit D3 is able to kill roof rats and other mammals via causing hypercalcemia. Excess calcium in kidneys and blood damages heart and vital systems. Rodents typically die in 2-5 days after feeding on the baits. The great disadvantage of the Vit D3 homemade baits is that they can be consumed by other non-target animals including cats, dogs, birds, weasels, squirrels. If they eat more than 2-6 of this toxic kibble or 2 poisoned rats, they will die as well. Thus, do not apply this method outdoors, and keep the bait out of the reach of children and pets. Moreover, wash your hands thoroughly after work with Vit D3.