White-tailed jackrabbit

It is a solitary individual except where several males court a female in the breeding season. Litters of four to five young are born in a form, a shallow depression in the ground, hidden among vegetation. This jackrabbit has two described subspecies: L. townsendii townsendii occurring west of the Rocky Mountains and L. townsendii campanius occurring east of the Rocky Mountains. The white-tailed jackrabbit is a large species of hare and is the largest species called "jackrabbit". This jackrabbit has an adult length of 22 to 26 inches (56 to 65 centimeters), including a tail measuring 2.6 to 4.0 in (6.6 to 10.2 cm), and a weight between 5.5 and 9.5 pounds (2.5 and 4.3 kilograms). From winter to spring, weight tends to increase in females due to pregnancy, but decrease in males due to the stresses of reproductive competition. Thus, females in Iowa went from averaging 7.9 lb (3,600 g) in winter to 8.4 lb (3,800 g) in spring and males from averaging 7.5 lb (3,400 g) in winter to 6.8 lb (3,100 g) in spring. At the northernmost extremity of its range, it can be almost twice as large as in the middle of its range.