How do I know if I have rats or mice?

Apart from the obvious situation where they are seen, their presence can be determined most easily by the presence of droppings. This is particularly true for mice where the droppings tend to be scattered. Rats often leave their droppings in a pile so these may not necessarily be seen. In addition the presence of mice and rats is often heard before there are any obvious visible signs or they may betray their presence due to damage to foodstuffs or other materials. A skilled pest control technician may also be able to identify smear marks, urine pillars, rodent hairs or minor rodent gnaw or scratch marks.