Common ravens belong to the largest order of birds in the world, the Passeriformes, commonly known as perching birds. Ravens have a wide distribution throughout the Northern Hemisphere, and can thrive in many habitats from tundra to desert. They are found in North America, Europe, Asia, and North Africa. The global population of common ravens is estimated to be about 16 million.
Ravens are very intelligent and can solve problems, recognize different individuals (including humans), and learn new behaviors by observing others. They are playful and have been seen in flight carrying objects such as sticks which they may trade back and forth with others. In addition, they play their own games by dropping and retrieving objects while in flight. They even appear to interact with other animals, including wolves, in a playful way.
Though not technically songbirds, ravens have a wide repertoire of sounds and calls, the most common of which is a croak that may rise in pitch. Other sounds include whistles, mews, shrill high-pitched alarm cries, and knocking sounds. Ravens can also imitate sounds such as dripping water, mimic other birds, and even learn to speak words in human languages.
Outstanding flyers, ravens are acrobatic and often move quickly and dive repeatedly, and are sometimes seen doing rolls and somersaults.
Ravens are excellent scavengers that will feed on almost anything including plants and animals, carcasses, and garbage. As predators, ravens will kill and eat small animals such as rodents, frogs, lizards, fish, scorpions, and insects. They will also raid bird nests, eating the eggs as well as the chicks. While their food habits can annoy or upset some people, their scavenging helps keep the environment cleaner.
Ravens will often hide (cache) food for later meals. They may even watch other ravens hide food, then raid that cache when the other bird is absent.