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. Male bobcats don't become sexually mature until two years old. Female can breed in their first year, but often do not. During estrus, a male may travel up to 20 miles in a single night searching for a receptive female. Radio telemetry research indicates that the male leaves the female after mating and plays no part in rearing young.