Rattus rattus

Other Names: Alexandrian rat, black rat, fruit rat and ship rat.

Body. Body is slender, 6 ½ to 8 inches (17 to 20cm) long. Average weight is 6 to 12 ounces (170 to 340 g).

Color. Varies from black to brownish-gray. The underside varies from gray to white.

Nose.
Nose and muzzle are pointed. Roof rats have an acute sense of smell.

Habits.
Able to swing, jump and climb, roof rats usually enter and nest in upper portions of buildings. May nest outside in trees (especially palm), ivy and similar vegetation. Burrow very little. Nocturnal. Most activity and feeding takes place between a half-hour after sunset and a half-hour before sunrise. Strong social hierarchy.

Teeth.
The gnaw pattern of rats is 1/8 inch. Rats are able to gnaw through wood, lead, aluminum, copper, cinder block and uncured concrete.

Tail.
Hairless and longer than the head and body-7 ½ to 10 inches (19 to 25 cm) long. Uniform color from top to underside.

Ears.
Ears are large and cover the eyes if bent forward.

Eyes.
Eyes are large and prominent. Because rats are colorblind and have poor eyesight, they primarily see light, shadow and movement.

Other names:
brown rat, gray rat, house rat, wharf rat, sewer rat, barn rat and water rat.

Ears.
Ears are close to the body and won't cover the eyes if bent forward.

Eyes.
Eyes are small. Because rats are colorblind and have poor eyesight, they primarily see light, shadow and movement.

Nose.
Nose and muzzle are blunt. Norway rats have an acute sense of smell.

Color.
Usually grayish-brown, but color may vary from a pure gray to a blackish-or reddish-brown. The underside is gray to yellow-white. Norway rats are often completely black.

Teeth. The gnaw pattern of rats is 1/8 inch. Rats are able to gnaw through wood, lead, aluminum, copper, cinder block and uncured concrete.

Droppings. Droppings have blunt ends and are about ¾ inch (2cm) in. Fresh droppings are soft and dark in color. A Norway rat averages 30 to 180 droppings per day.

Tail. Tail is shorter than head and body-6 to 8 ½ inches (15 to 22cm) long. Tail is dark on top with a lighter underside.

Body.
Body is heavy and thick, 7 to 10 inches (18 to 25cm) long. Average weight is 10 to 17 ounces (284 to 482 g).

Habits. Norway rats burrow extensively in soil and are excellent swimmers and good climbers. They usually nest in basements and lower portions of buildings. Nocturnal. Most activity and feeding takes place between a half-hour after sunset and a half-hour before sunrise. Very strong social hierarchy-the biggest and strongest Norway rats get the best food and harborage.

Food Preferences and Consumption. Omnivores. Meats, fish, flour, cereal grains, fruits and vegetables. Eats almost any human food. Rats visit fewer food sites than mice, but eat more at each site. Consumes ¾ to 1 ounce of food each day. Requires water daily to survive-drinks ½ to 1 ounce of water daily.

Facts:
Rats explore their territory of 100 to 300 feet daily.
Rats can swim up to a mile.