Raccoons are found throughout most of North and Central America (Procyon lotor) except for the arctic regions, and most of north and central of South America (Procyon cancrivorus) except for the high Andes and the Pacific Coast. They have been introduced to Europe, the Caucasus, and Japan. They are common in forests, marshes, and mountains, always near water, and have adapted to living in cities. Raccoons rely on climbable trees or other vertical structures for refuge, and are only found where these are available. When possible, they nest in trees. Mass is highly variable, between 2 and 12 kg, although the males of a given population are about 20% heavier than the females.
Raccoons are mostly nocturnal, although they may be active during the day to exploit day-available food resources. They are omnivores with a broad diet - assorted invertebrates (such as insects, crayfish, and worms - the latter of which are often detected by sound underground), small vertebrates (such as fish, frogs, and bird eggs), fruit, nuts (such as acorns and walnuts), grains, and vegetables. In inhabited areas they will raid croplands and garbage containers.
Raccoons have extraordinarily sensitive hands, which they use to explore the world and forage for food in the water, among vegetation, and under rocks. The long fingers have a great many nerve endings, as well as vibrissae around the tips of the fingers. These hands can also grasp and manipulate, although they lack an opposable thumb and a precision grip. Food is usually investigated with the hands, and often processed by removing inedible parts. In captivity they often dunk their food underwater before eating it, but this is not seen in the wild.
Raccoons are solitary most of the time, but they do form social arrangements. Related females may share a home range and gather together from time to time, while males may form loose alliances to drive off rivals during the mating season.