How can you tell the difference between possums and rats?

Possums are nocturnal and therefore active at night. They often make loud thumping noises in the roof, and screeching, disturbing calls. Rats are also common in rooves, and you will hear them scampering about. You may also hear rats gnawing on wood surfaces or timber frames and other materials. Without a proper inspection it can be very hard to tell by just the noises. You may have both rats and possums.