Brown Rat

Where it lives in Maltese properties

Burrows in soil banks, under sheds and rubble walls, along wied (valley) beds, in sewers and beneath ground-floor slabs. Rarely far from food waste and water.

Signs of an infestation

You will usually notice the evidence long before you see the pest itself. Look for:

• Dark tapered droppings 15–20 mm long, often in runs
• Smooth greasy smear marks along walls, pipes and beam edges
• Gnaw damage to cables, packaging, doors and plastic pipework
• Burrow entrances 7–12 cm across near walls, drains and rubble
• Scratching and running sounds in ceilings, walls and roof voids at night

Why it matters

The risks associated with brown rat in Malta:

• Transmits Leptospirosis (Weil’s disease), Salmonella, Hantavirus and Toxoplasma
• Gnawed electrical cabling is a documented cause of building fires
• Contaminates food stock and packaging, forcing costly disposal
• Undermines paving, drainage and foundations through burrowing
• Automatic failure point in any food safety audit

How to prevent it

Prevention is always cheaper than treatment, and for this species it is genuinely effective:

• Seal every gap larger than 20 mm. Rats get through far less than people expect
• Keep refuse in rodent-proof bins with closed lids, away from the building
• Repair defective drains, gullies and manhole covers
• Cut back vegetation and clear rubble against external walls
• Never leave pet food, bird feed or compost accessible overnight
• Check the drain runs. A defective interceptor under the yard is the most common way rats get into an otherwise sound building

How we treat brown rat

We survey to find the harbourage and entry routes, then combine tamper-resistant bait stations, break-back trapping and, most importantly, physical proofing so the population cannot return. Rodenticide use follows the CRRU stewardship rules: never placed in the open, always recorded, and removed once activity ceases. A typical programme is three to four visits over six weeks.