Rats and mice - telling the difference
To many people and cultures rats and mice are seen as the same animal; mice are thought to be young rats. However, they are distinctly different animals, with their own life cycles, habitats, health issues etc. This is intended to help you identify which of the two you have seen or have in your home.
Although there are a number of rat and mouse species the two most likely to be seen in and around the home are the common rat also known as the Norway rat, the Brown rat or Sewer rat. Mice are usually the House mouse, but sometimes field mice are seen as well.
It is important to identify which you have in your home or garden as the treatments differ and the advice and help we give will also differ. For example we do not treat mice outside, but we will for rats. Rats can often be a symptom of another problem ie a drainage defect and we can advise accordingly. Proofing advice to stop the rodents getting in may also vary greatly.
| Rats | Mice | |
| Adult weight | 300 grams (11 ounces) | 15 grams (half an ounce) |
| Length (head & body) | 200-250 mm (8-10 inches) | 60-90 mm (2-4 inches) |
| Length (tail) | 150-200 mm (6-8 inches) | 80-100 mm (3-5 inches) |
| Total length | 350-450 mm (14-18 inches) | 140-190 mm (5-9 inches) |
| Fur colour | Brown to black on upper head and body, lighter undersides | Brownish grey, but lighter shades do occur |
| Ears | Thick, opaque, small relative to the overall head size and covered in fine hairs | Large relative to the head |
| Head and snout | Heavy blunt and chunky | Small and sharply triangular with pointed muzzles |
| Tail | Shorter than body, thick and heavy | Longer than the body, thin |
| Eyes | Small | Large and prominent |
| Droppings | Usually found in groups, spindle shaped, about 20mm (3 quarters of an inch) | Scattered, rod shaped, 3-6 mm(eighth to 2 eighths of an inch) |