[2] Throughout this range, Ammospermophilus leucurus is omnivorous, feeding primarily on foliage (10%-60% of its diet), seeds (20%-50%), arthropods, and to a lesser extent, vertebrates (mainly lizards and rodents; predatory behavior by ground squirrels has been noted[8][9][10][11]).

[12] In conjunction with being a predator, the white-tailed antelope squirrel is also prey to many larger animals, including raptors, various canids, and snakes.

[2][13] Although these animals live in hot and arid climates, the white-tailed antelope squirrel is diurnal, meaning heat gain from metabolic activity could be a problem.

In Oregon, which is the northernmost extent of the squirrels' range, reproductive cycles are relatively short, and the average litter size is 9.3.

However, in Baja California, the southernmost extent of the squirrels' range, reproductive cycles last half of the year, and the average litter size is 5.9.