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Roof Rats

Roof Rats

Roof rats in the desert? Yes! Also known as a black rat or ship rat, this species (Rattus rattus) became a common sight, and a nuisance, in Phoenix area neighborhoods in the early 2000s. The Roof Rats have likely migrated down from Phoenix by rail cars. I have heard of sightings of Roof Rats around the railroad tracks and now the Sam Hughes neighborhood in Tucson.

Roof Rat Facts

They are usually dark in color, slender, and 7-8 inches long. It also has a dark, scaly tail that measures longer than its entire head and body. Most active in the evening hours, they spend 80% of their time 4 feet or more off the ground in shrubs, trees, power lines, or roofs. They are agile jumpers and can find their way into attics, basements, garages, patios, a house’s walls, or cabinets.

Here are some frequently asked questions regarding these critters:

  1. What Are Common Signs of Roof Rat Activity?
    Hollowed out citrus (their favorite food), rat droppings, noises in the attic or walls, gnaw marks on roof eaves, damage to electrical wire coverings, or dark ‘trail’ marks on block walls.
  2. How do Roof Rats Get into a House?
    They can enter through any opening larger than a nickel in size. They follow pipes from the attic or basement, gnaw through drywall or siding, and have been known to enter through the sewer system from a roof vent pipe or on occasion, through the toilet plumbing.
  3. Roof Rats in the Sewer?
    The City Water Department and Wastewater Collection Division should monitor these as the sewer system can help spread them into other areas. If found an aggressive program to trap and remove roof rats that may find their way into the sewer. If found in the sewer system a trapping program should be quickly set up and monitored.
  4. Do Roof Rats Carry Diseases?
    Roof rats throughout Maricopa County reportedly have tested negative for tularemia (rabbit fever), hantavirus, and the plague.
  5. How do I Keep Roof Rats Away from My House?
    Keep citrus trees pruned, pick up dropped fruit from the ground, and remove unwanted fruit at the end of the harvest season. Remove fruits and nuts that drop into your yard. Store all dog food in sealed containers and do not leave it out overnight. Seal all holes and vents leading into your house with a wire mesh or screen material and caulk cracks. Eliminate vines that grow on buildings and keep overhanging tree limbs pruned. Exterminators can play a big part in helping with a prevention or removal program.