Two East Valley cities are in the top 10 nationwide, but not in a category they want.
Gilbert and Tempe are among the worst in the country for roof rats based on data compiled from more than 300 Terminix branches.
Gilbert ranked 2nd and Tempe ranked 5th on the list.
Joel Whalin, the service manager at the Tempe Terminix branch, said that the influx of rodent infestations could be because they're migrating through the Valley and looking for basic necessities.
"What it all boils down to is do have what they need to survive," Whalin said. "That's food, water and shelter."
The main signs of an infestation include droppings, the smell of urine, chew marks on the property, rat noises at night, and holes in fallen citrus fruits.
The scent of rodent urine is very sweet and difficult to describe but distinguishable, Whalin said.
Citrus plants are a primary food source for rodents, so if homeowners don't pick up fallen fruits, that can attract unwanted critters. Homeowners will often see holes in fallen, rotten fruit, which is a sign that rodents are feeding on their property, Whalin said.
If rats have breached a structure, squealing and gnawing can be heard at night due to roof rats' nocturnal nature.
"Homeowners will hear a lot of noise going on that typically you wouldn't hear in the middle of the night," Whalin said.
Even if rodents haven't entered a structure, pests around a home can still cause issues on the exterior and can lead to roof rats making their way into a house, Whalin said.
"The reality of it is that there are rats outside and they're running around everywhere," Whalin said. "Even though they may not breach a structure and get inside a home, they will still chew on things because there is food and water available."
The damage that rodents can create inside of a home can affect both the structure of a house and the health of homeowners.
Rodents are capable of chewing through electrical, plumbing and gas lines. Pregnant females are even able to chew right through a wall to find a dark and quiet place to have their babies, Whalin said.
The urine and feces of rodents can contain bacteria that can be harmful to a homeowner if they come into contact with it or ingest it.
"It's not only about where they can cause physical damage to a home but buildup of their droppings or urine can potentially become a health hazard for the homeowners," Whalin said.
The best way to prevent an infestation is to eliminate all potential food sources for the rodents. Homeowners should pick up fallen fruit so rodents won't be attracted to the area, Whalin said.
Another potential food source can be dog food and water that is left outside, Whalin said.
"I'm not saying, especially in Arizona, not to leave food and water out for animals, but just know it can potentially attract rodents," Whalin said.
Once it is evident there is a rodent infestation, the way a Terminix team handles the situation is by first identifying the kind of rat they are dealing with so they can decide the best way to eradicate it, Whalin said.
Then the team begins the process of trapping the rodents by first placing unset traps with bait around an area.
Once the roof rats take the bait, the team goes back and sets the traps with new bait, Whalin said.
"The caution that the rodent has is gone, it feels comfortable feeding in that area and then we'll get them," Whalin said.
Whalin said he strongly advises against homeowners trying to deal with an infestation on their own.
"Unless you know what you're getting yourself into you'll be chasing your tail," Whalin said.