Other food items included deer mice, sagebrush voles, meadow voles, mountain cottontails, and white-tailed jackrabbits. Desert cottontails, jackrabbits, and Merriam's kangaroo rats come out at night. The desert cottontail, like all cottontails, eats on all fours. Louisiana has two species of rabbits&colon; eastern cottontails and swamp rabbits. For example, hares have a greater resistant to fatigue than cottontails. Marsh rabbits have a number of features that distinguish them from cottontails and swamp rabbits. Desert cottontails, kangaroo rats and mule deer are commonly seen by visitors. Eastern cottontails eat vegetation almost exclusively; arthropods have occasionally been found in pellets. Juvenile eastern cottontails are rare in the diet of short-eared owls ("Asio flammeus"). In Pennsylvania, the chief predator of eastern cottontails is the great horned owl. In New England female eastern cottontails have three or four litters per year. In summer, eastern cottontails consume tender green herbaceous vegetation when it is available. Eastern cottontails also consume many domestic crops. The tail is also much reduced from the bushy tail seen in cottontails. Generally, the testes of the male New England cottontails begin to enlarge in late December.