DESCRIPTION: Wt=21-28 oz (600-800g); L=17-21" (430-540 mm) with the tail another 7-10" (172-252 mm). Largest ground squirrel in its range (southwest). Grayish-brown and mottled above, lighter below. Long, bushy tail and large ears make it look like a tree squirrel, but it spends most of its time on the ground.
NATURAL HISTORY: Omnivore, feeding on plant material, insects, birds and their eggs, small rodents (I saw one carrying a Packrat in its jaws), and carrion. Diurnal. Solitary or colonial. Look for them scampering over the "rocky" exhibits at the Arizona-Sonora Desert Museum.
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