How to Tell a Rat From a Mouse

Upon spotting a furry little rodent running across the kitchen floor, you may not want to get close enough to inspect it to see whether it is a rat or a mouse. Since exterminating methods may differ for the two animals, it may be in your best interest to be able to tell a rat from a mouse. Learn the methods to tell the difference between the two.

Difficulty:

Moderately Easy

Instructions

1. Observe the size of the rodent. If it is medium-sized (around nine inches long) and has a thick, longish tail (around seven inches long), it is a rat. If it is the size of a small bird (about four inches long) and has a long, very thin tail (about four inches long), it is a mouse.

2. Count the rodent's nipples (assuming it allows you to do this). Rats have six pairs of nipples, but mice only have five pairs.

3. Look at the animal's head. A rat has a large, thick, stocky head, whereas a mouse has a small, pointy, triangle-shaped head. A rat's ears are also smaller in proportion to its head than a mouse's.

4. Examine the rodent's feces. Mouse droppings are very small and numerous; you may see 10-20 tiny "pellets" in a pile. The ends of a mouse's feces are pointed. Rat droppings are larger (about 1/2 to 3/4 inches) and more sparse. Rat feces may appear curved.

5. Inspect your walls for rat rubmarks. Rats tend to use the same paths when walking around your house and like to keep at least one body part touching the wall at all times. Because of this they leave greasy "rubmarks" along the walls. An absence of rubmarks may indicate a mouse infestation.

6. Check for gnaw marks around the house. Rats gnaw on wood frequently to keep their incisors in shape. Mice do not chew as much.