Recognising Rats: 7 Signs of an Infestation
Rats are cautious animals that rarely reveal themselves during the day. Yet they leave behind plenty of evidence. Know the signs and act quickly — rats reproduce at a staggering rate.
The 7 signs
1. Droppings
Rat droppings are 8–12 mm long, blunt at both ends and dark brown in colour. You will find them along walls, in corners and near food storage.
2. Gnaw marks
Rats must constantly gnaw to keep their teeth worn down. Typical gnaw damage includes:
- Rounded holes in woodwork, drywall or plastic
- Chewed food packaging or cardboard
- Damaged electrical cables (fire hazard!)
3. Grease marks (run trails)
Rats always follow the same routes along walls. The oils and dirt in their fur leave dark grease smears on walls and beams.
4. Burrows and tunnels
Outdoors: holes of 6–9 cm in diameter in the ground, often under patio slabs, sheds or compost heaps.
5. Sounds
Rats are active at night. Listen for:
- Scratching and running sounds behind walls or ceilings
- Squeaking (young rats)
- Gnawing noises
6. Nests
Rats build nests from torn paper, cardboard, fabric and insulation material. Often found in dark corners of the crawl space or under floorboards.
7. Live or dead rats
Seeing a rat during the day is a serious warning sign — the colony is likely already large.
What next?
Rats pose a genuine health risk (leptospirosis, salmonella) and cause structural damage. Contact a certified pest controller immediately.
Tip: Check with your neighbours too — a rat infestation rarely stays confined to one property.