Resting for about 1 hour is followed by a long period of feeding through most of the morning. Near midday, another extended period of lying down occurs, succeeded by one or two feeding periods during the afternoon. When the heat of the day is intense in spring and summer, little activity takes place. After about 5 p.m., pronghorns feed steadily until nightfall, at which time they recline for a long period of rest. The alternation of feeding and resting is repeated at night, with longer periods of lying down than during the day.
Pronghorns feed entirely upon vegetation, chiefly shrubs and forbs.
All parts of the plants were consumed including leaves, stems, flowers, and fruits. Pronghorns have a particular fondness for flowers and fruits. The flowers of cutleaf daisy, white daisy, stickleaf, paper flower, and woolly senecio are consumed in large amounts. Although paper flower is poisonous to sheep and woolly senecio is poisonous to cattle, pronghorns apparently suffer no ill effects from either and consume large quantities of both. More browsing is done in fall than in summer.