Norway rats originated from Asia and arrived in North America in the mid-1700s via Europe ships. They are also known as wharf rats, sewer rats, street rats or brown rats. They are larger compared to roof rats weighing a pound and 12-18 inch long when fully grown. They are omnivorous, feeding on a range of food sources. A female Norway rat can wean 20 or more offspring annually. They are generally the largest rats in most parts of the world. Although they can climb, they prefer basements and the ground floor. Knowing the difference will make controlling them much easier and simpler.
Risks of Norway Rats
Norway rats can be carriers of different diseases that can be transferred to humans via faeces and urine. Apart from that, they can cause some damages to a building: this may include damaging the foundation with dug burrows, chewing on belongings or wiring, contamination of food, among others.
Signs of Infestation
- Gnaw marks
- Grease stain from their movement
- Visually seeing them or hearing sounds.
- Droppings
- Burrows
Prevention and Control
First, you have to make sure that there is no holes or open entries the rats can get through; this includes electrical and plumbing units. The size of the hole or entrance does not matter as the rats can gnaw and enlarge the hole. Norway rats and other rats, in general, can flatten their bodies to squeeze through tiny holes: once the head is in, they can manage to pass.
Many places handling food like warehouses or restaurant use outdoor rat poisoning. Outdoor poisoning is placing baits outside the building or premises. This keeps the rats from finding a way to get inside to the food source they are sniffing. The rats first find the baits and feed on there, keeping them happy and outdoor.
Indoor trapping is another control method. Since using rodenticide baits indoor is not encouraged, trapping is encouraged instead. Rodenticides are discouraged because of the increased chances of the mice or rat dying within the premises, which may result in the carcass smelling till it is dehydrated.
For indoor trapping, a Snap Trap is highly suitable and efficient for getting rid of Norway rats within premises. Once the rat is caught, it cannot escape. You can also use a live trap to capture Norway rats.
Apart from the control mentioned above ways, the other methods that could be applied include; Container sealing; all garbage cans should be emptied regularly and be properly sealed. Also, entryways blockage is an applicable method; open doors and windows should be closed, especially at night since rodents are most active then. Gaps should be filled up, ensuring no passage is left open. Further ore, food sources should be reduced, all fallen pet food should be cleaned up, and the rest kept out of reach since Norway rats feed on them.
Finally, reducing water sources is an easily applicable method to keep Norway rats out of your home. Sprinklers and spigots should not be dripping. A plumber should fix any leaks within the homestead.