What physical feature helps differentiate roof rats from Norway rats?

The distinctive nose shape is a key feature that helps differentiate roof rats from Norway rats. Roof rats (Rattus rattus), often referred to as black rats, have elongated, pointed snouts which give them a more streamlined appearance. In contrast, Norway rats (Rattus norvegicus) have broader, blunter snouts. This difference in nose shape is just one aspect of their overall physical characteristics, which can assist pest control technicians in accurately identifying the species when addressing rodent infestations.

While eye size, weight, and tail length may have some differences between the two species, they are less reliable for identification purposes in practical scenarios. Eye size can vary widely within a species and is not a definitive distinguishing feature. Similarly, weight varies significantly based on age and health, and although roof rats typically have longer tails than Norway rats, tail length can sometimes overlap, making it a less effective identifier in certain situations. Understanding the subtle differences, like nose shape, is crucial for pest control professionals when developing targeted management strategies.