Roof Rat Identification

Some characteristics that can be used to identify rat species:

 Wood Rat (Pack Rat)    Cotton Rat Roof Rat (Black Rat-Ship Rat)    Norway Rat

Wood Rat
(Pack Rat)

Cotton Rat

Roof Rat
(Black Rat, Ship Rat)

Norway Rat
Size
Head and body 6-8 inches Head and body 5-7 inches Head and body 7-8 inches Head and body 8-10 inches
Tail
Hairy. Bicolored, lighter below. About as long as head and body combined, 5-8 inches. Scaly, sparsely haired. Bicolored, lighter below. Shorter than head and body combined, 4-5 inches. Scaly. Dark color. Longer than head and body combined, 8-10 inches. Scaly, nearly hairless. Darker above, lighter below. Shorter than head and body combined, 4-8 inches.
Color
Gray to grayish-brown with lighter feet and underbelly. Coarse, blackish to grayish fur. Black guard hairs cause a grizzled appearance. Several color phases. Tends to be blackish with a lighter underbelly. Brownish-gray above, grayish below.
Ears
Large, hairy. Large, but nearly concealed by fur. Large, nearly naked. Small, covered with short hairs.
Snout
Blunt Blunt with high "Roman" nose. Pointed Blunt
Droppings
Blunt, 1/2 - 3/4 inch long, 3/16 - 1/4 inch diameter. Pale greenish or yellow, 3/8 inch long, 3/16 inch diameter. Pointed, banana shaped, 1/4 - 1/2 inch long, 3/16 inch diameter. Blunt ends, 3/4 - 1 inch long, 1/4 - 3/8 inch diameter.
Mammary Glands
2 pair 2 pair 5 pair 6 pair