THE ROOF RAT Identification and Biology

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Roof Rats may be identified by the following physical features:

  • The Roof Rat's adult head and body length is about 13 to 18 inches long, including its tail.
  • The Roof Rat appears sleek and graceful. The Norway Rat is larger and more robust.
  • The Roof Rat has a pointed nuzzle, and ears that are long enough to be pulled over its eyes
  • The tail of the Roof Rat is about 4.3 inches on average, and black with fine scales
  • The easiest way to distinguish Roof from Norway Rats is to pull the tail back over the body. That tail of the Roof Rat will reach the nose, while the tail of the Norway Rat will only reach to the ears.

Other Identification Helps:

  • Droppings- Rat droppings are long and cylindrical
  • Tracks- Roof Rats and Norway Rats leave a hind foot track of about 3/4-1 inch. A mouse's tracks will be much shorter. Rats will also drag their tails, leaving a mark between their feet tracks.
  • Gnawing holes- Gnawing holes from rats are about 2 inches or more in diameter and will have rough edges. They prefer gnawing on wood but may also damage electrical wiring.


Roof Rats are less adaptable than Norway Rats, preferring warmer tropical climates. Roof Rats are also very agile climbers. For this reason they may often live in attics or trees, and frequently enter buildings from the roof or by way of utility lines (thus the name, "roof rat"). Roof Rats are also commonly found within landscaped residential and industrial areas, vegetation of streams and riverbanks, citrus or sugarcane groves, and in and around farms or poultry houses where food and shelter are abundant.

Food Sources

Roof Rats will eat almost anything including paper and plant material, but prefer fruits and nuts when they are available, as well as animal feed.


Roof Rats are primarily nocturnal, meaning that they sleep during the day and become active (seeking food and water) after dusk. They often live above ground (in attics or trees) and travel down at night to find food sources. This makes traditional baiting and trapping on the ground or floor a bit trickier. Unless traps or baits are placed at the very point of entry that Roof Rats travel from above to a food source, very few of them will be intercepted. Roof rats also have a tendency to avoid new objects in the environment and may take a few days to approach a trap or bait, which can also influence control measures. If possible, you will want to actually bait or trap for Roof Rats at a higher level, such as in the attic or atop the roof. Removing vines or low hanging branches from around your home or building will also speed control.

Life Cycle

Roof Rats give birth to about 5 to 8 young after a gestation period of 21 to 23 days and may have up to 4 litters a year. Newborn rats may reach independence and reproductive maturity at about 3 months. Peak breeding season for the Roof Rat typically occur in Spring and Fall.

Products for Control of Roof Rats:

Read More:

How To Get Rid of Roof Rats

Baiting Tips for Roof Rats

View all Rat Control products


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