Rats are various medium-sized, long-tailed rodents. “True rats” are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus. Many members of other rodent genera and families are also referred to as rats, and share many characteristics with true rats.
How To Identify Signs of Rats
As nocturnal creatures, rats are most active between dusk and dawn and usually hide from humans during the day. It is often easier to spot signs of a problem, rather than the actual pest.
- Rat Droppings – usually found in concentrated areas as rats produce up to 40 droppings per night. Brown rat droppings are dark brown in a tapered, spindle shape about 9–14mm long. They can resemble a large grain of rice.
- Scratching Noises – Think you might have rats in your roof? Black rats (also known as the roof rat) are agile climbers and can easily gain access into loft spaces and upper floors of buildings. Hearing scratching noises at night from above may suggest their presence. Brown rats on the other hand, are less adept climbers. You may hear them scurrying under decking, sheds and floorboards. They are more likely to be identified by a grinding noise they make with their teeth known as bruxing.
- Footprints (running tracks) – Rats leave foot and tail marks in dusty, less-used areas of buildings. Shining a strong flashlight at a low angle should reveal tracks clearly. To establish if an infestation is active, sprinkle fine flour or talc along a small stretch of floor near the footprints and check for fresh tracks the next day.
- Rub Marks – Rats use established routes along skirting boards and walls due to their poor eyesight. Grease and dirt on their bodies leave smudges and dark marks on both objects and surfaces they repeatedly brush against. These marks may indicate rodent activity, but as smears may remain for a long period of time, they are not a good gauge of an active infestation.
- Damage – Rats have teeth that grow continuously. They need to gnaw on wood and plastic to keep them trim. They have the potential to cause fires by chewing through electrical cables. You may also notice ripped food packaging, as rats tear open food, leaving visible teeth marks.
- Nests – Rats build nests in warm, hidden places using shredded material such as newspaper and fabrics. Nests will often contain young rats and are usually located close to a food source. Check behind and under appliances, such as fridges and freezers in or near your kitchen.
- Burrows – Brown rats are well known for digging and excavating extensive burrow systems for shelter, food storage and nesting. Look for burrows in compost heaps, under decking or garden sheds, or in garages.