Family: Muridae, Mice and Rats view all from this family
Description A stocky mouse. Grayish or pinkish cinnamon above; white below. Thick, short, bicolored tail with white tip, between a third and a half the total length of the animal. Juvenile gray. L 4 5/8 –6 3/8" (119–163 mm); T 1 1/4–2 5/8" (32–68 mm); HF 3/4–7/8" (18–23 mm); Wt 3/4–1 oz (22–30 g).
Similar Species Northern Grasshopper Mouse is larger, with shorter tail. Deer mice have longer, thinner tails lacking white tip. Mearns’ Grasshopper Mouse is more reddish brown, with shorter tail.
Breeding Most reproductive activity May–July; litters of 1–5 young; gestation 27–30 days.
Habitat Low desert with creosote bush, mesquite, and yucca.
Range Southern California, w and s Nevada, and extreme sw Utah, southeast through w and s Arizona, s New Mexico, and w Texas.
Discussion The Southern Grasshopper Mouse, like its relatives, is primarily nocturnal and is active throughout the year. The home range of the male extends up to 8 acres (3.2 ha), an unusually large area for a small rodent. Although this species eats small amounts of seeds, its diet consists almost entirely of animal material: scorpions, beetles, grasshoppers, and other small mammals, especially harvest and pocket mice. Like the large carnivores, grasshopper mice have developed efficient strategies for dispatching prey. When capturing certain beetles that produce a defensive secretion from the back of the abdomen, grasshopper mice hold the beetles in their forepaws and jam the abdomen into the sand to avoid the secretion. They kill small mammals with a bite through the back of the neck. Before killing scorpions, they immobilize the deadly tail. The Southern Grasshopper Mouse either digs its own burrow or appropriates the burrow of another small mammal. The social unit includes one pair and its offspring per burrow system. The male and female both actively care for the young, although the male is excluded from the nest by the female for the first three days after birth. The highly territorial male employs a high-pitched, wolf-like call to ward off other males.

