Rat field guide
Identification of small mammals from photos is uncertain. It helps to have multiple photos, preferably with a scale in all images, showing: the ratio of tail-length to body-length; the nature of the ears, including how far the ear lobe will reach, in relation to the eye, when the ear lobe is folded forward; the pads under the hind feet; the fur above and below the body, any markings on the head or face; and the scales and fur on the tail.
