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• Roof Rat

Rattus rattus

The roof rat is native to forested areas in Southeast Asia, and is now commonly found in the United States. Less widespread than the Norway rat, it is most prevalent within 100 miles of coast lines on both the east and west coasts. It is also referred to as the black rat, ship rat, or tree rat.

Roof rats are smaller and slimmer than Norway rats. Adults are 6-8 inches in length (combined head and body), with a tail 7-8 inches long. They usually weigh 5-9 ounces, but have been known to reach up to 12 ounces. Coloring is usually brown with some black or a dark gray with black, with a lighter gray to brown abdomen. Other distinguishing differences include a pointed nose, large eyes, and large ears (with very little hair) and a tail that is longer than its head and body combined. The tail appears scaly and consistently dark in color. They are excellent climbers, jumpers (vertically up to 3 feet) and can swim well when necessary. They have very poor vision, are colored blind, and are considered nocturnal.

Less prolific breeders than the Norway rat, the roof rat is reproductively mature by 2-5 months of age. Females usually have 4-6 litters per year, with 6-8 young per litter. Gestation is about 22 days. The average life span of a roof rat is 5 to 18 months.

Favorite foods include: fruits, vegetables, nuts, garden snails and cereals but they will eat nearly anything. They do tend to become food/bait shy if foods are disagreeable to them and will search out a new source. Once they find an acceptable food they will eat their fill and then continue to return time after time. They require ½ to 1 ounce of food each day and about an ounce of water. Often that water comes from a food source rather than a separate source.

Outdoors, the roof rat prefers to live above ground level in trees but cam occasionally be found in burrows or vegetation around a structure. As temperatures drop, they may search shelter and/or food sources and find their way inside of a home. They can travel back and forth by means of wires and cables that are attached or enter into the home. Once established indoors, they prefer to nest in upper parts of the structure such an attic space.

Signs of infestation can include: gnaw marks, droppings (adults - about ½ inch in size), tracks/footprints, rub marks, and burrows or runways.

Important preventative measures include:

1. Removal of food sources.
2. Removal of debris or anything which could be considered a "harborage site".
3. Removal of shrubbery or branches overhanging structure rooflines.
4. Securely seal cracks, gaps, and openings around doors, window frames, foundations and siding - keeping in mind that any such area 1/2" or larger is considered a point of access.

While there are many "self-treat" methods available such as traps and rodent bait or poisons, we strongly recommend no baits or poisons are used unless any interior infestation has been eliminated and access points repaired. Because baits and poisons are very fast acting, rodents may not be able to find an exit point before expiring which can leave to sever odor problems. We recommend these products be used only on the exterior of the home.

If populations remain in excess then a call to Long Pest Control can develop an Integrated Pest Control program to eliminate the sightings and provide control of unwanted rodents year round.