A ruff of fur extends out and downward from the ears. The bobcat's rangy, muscular back legs are longer than its front legs. This gives the animal a high-tailed, bobbing gait when it runs. Bobcats are mainly nocturnal, but they sometimes venture out in the daytime. Two other eye adaptations that help night vision are abundant light-sensitive rods and a reflecting layer that makes an object stand out sharply from its background.
Bobcats are colorblind and see only in shades of gray.
But like most other predators, cats are opportunists, and porcupine, mink, muskrat, skunk, fish, frog, insect and fox remains have also been found in their stomachs. Occasionally bobcats take sick, weak or crippled deer, but predation by 'cats has little or no effect on the size of Pennsylvania's deer herd. After feeding on a deer, a bobcat may cover the rest of the carcass with leaves. Bobcats also feed on whitetails which have starved during winter or died of other causes. Breeding takes place from late February to early March.