Which of the following is NOT a common method to identify rodent presence in a structure?

Identifying rodent presence in a structure typically relies on several common signs. Observing food rats might be confusing in this context; it implies directly seeing the rodents, which can be rare especially at the early stages of an infestation. Instead, pest control professionals often rely on indirect evidence, such as finding urine stains, hearing noises, or tracking droppings.

Urine stains are indicative of rodent activity, as rodents often urinate as they move about their environment, which can lead to detectable marks. Strange noises, such as scratching or scurrying sounds, often help indicate that rodents are present, especially during the night when they are most active. Tracking droppings is another crucial method, as rodent droppings can reveal the species present and the severity of the infestation.

In contrast, observing food rats involves directly witnessing the animals, which may not always be feasible or reliable as a method of detection. This makes it less common as a primary means of identifying rodent presence compared to the other methods listed.