| Some characteristics that can be used to identify rat species: |
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| 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. Longr 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 |