Ravens are members of the genus Corvus in the family Corvidae. Older sources list them as members of the genus Carrion, hence “corbies” or “crows”. Among birds they are perhaps most closely related to the rook and jackdaw of Europe (=Corvus frugilegus).
Larger than crows, ravens typically measure 40–64 cm (16–25 inches) in wingspan and weigh 540-880 grams (1.2-2 pounds). Ravens mostly live in lowland valleys at high latitudes or mountainous areas with some timber for roosting and nesting such as fields, meadows and forests beside large bodies of water.
Ravens are very social birds, and live in flocks of six to 30 or more. They eat a wide variety of food such as carrion, insects, eggs and small animals.
They are even known to eat roadkill or other dead animals that they find on highways in the winter.
A group of ravens near each other is called a “flight”. If a group is in the air and moving, it’s called a “chase.”
A “fledgling” or nestling is the young bird that has just hatched.
Since the number of people who have asked this question seems low, I’m going to answer Wylis’ follow up question: What are some quintessential behaviors of ravens? For her next New Year resolution challenge.
Ravens do many things simultaneously while engaging in what we call polysemous behavior, alternating between different means of achieving their goals depending on whether those actions provide more reward than alternative courses of action.
Ravens form large, loosely packed groups of birds. They are known to fly and roost together, though they don’t have many strong social bonds like the ones typically seen in flocks of geese.
Birds will sometimes motor from large daytime feeding areas to nighttime resting sites in ‘raven flights’. When there is migration or nomadic movement at night, such as with shorebirds or red-winged blackbirds that don’t perch during the day, these groups of migrating birds (such as corvids) leave their safe nesting site and may be vulnerable to robbers, such as other carnivorous birds; hence when ravens flock together at night this way it can make them safer. It may also enable communication and safety in numbers.
Ravens will also assemble alongside other species, such as magpies and dogs (this is why ravens and dogs don’t typically get along well).
There are reports of ravens nesting in massive aggregations, or ‘raven cities’ where thousands have been seen together. Ravens have been observed to nest in large groups when there is a high population of food sources, such as salmon runs.
A flock of ravens is group of ravens that have gathered together.
A “flock” is a bird flight formation where many birds fly in close proximity to each other, usually no more than 25 feet apart at the closest points. Flocks can come together spontaneously or they can be man-made by people like the huntsman who may create large flocks for hunting. The term “assembly”, which should not be confused with the word assembly as to propose a law, describes when smaller groups join into one large group and end up making one pile from all their joining bodies and minds. This is what my paragraph below about the two functions of a flock: One function as an assembly point away form predation risk (like under a rock overhang or in a thicket of bushes) and the other function is to roost where they sleep at night.
If a group of ravens is sitting together, or if they fly off in a compact formation, this is called a “flock.”
The raven is an intelligent and unusually large song bird found around the Northern Hemisphere. They’re omnivorous so there isn’t one type of food that makes them happy. Some people have noticed that you’ll see more than one raven at a time; when most animals live in small groups this has been called the “law of threes”. That’s why it may be easier to find raven flocks rather than finding just one – making it easy to understand how they were considered clever scouts for fallen prey and willing messengers between worlds in mythology. You may often hear their guttural call before finding their large, ebony silhouette. Ravens are said to be the smartest of all birds, with an average I.Q. in tests on par with some great apes.
A group of ravens is called a ‘murder’.
This may be because the Norse god Odin, like Zeus in Greek mythology, took on the form of a raven or because they would often eat carrion and act as scavengers. It might also have something to do with their raucous cawing.
Biologists, citing information from Jerry Lemenuik’s book Michigan’s Crow Country, claim that when traveling in search for food in an unfamiliar territory they rely on one bird for directions until it spots familiar landmark (such as an old nest) where they go to roost at night and next day birds come out one by one.
A bunch of crows.
Americans often call all types of large black bird “ravens”, but technically they should be using the word more specifically. To get technical, a true raven is found in a few species that are from the genus Corvus, and you can tell by their striking blueblack feathers and yellow bill. They’re very intelligent birds that are known to produce human-like sounds. Crows, which we usually visualize as grey or blue feathers with an infamous harsh “caw” sound, aren’t technically ravens – they belong to a different genus of corvids called Gymnorhdae).
A group of corvids is called a “murder”. It’s used to scare people. For example when somebody has managed to get away with something that was supposed to be impossible (sort of like in the Lion King!), you might say “it took a whole murder of ravens to do it.”
The word ‘raven’ also means, figuratively speaking, one who tells bad news; or one who would betray another person’s confidence.
That bad news-bringing meaning relates back to an old Anglo-Saxon superstition that if a bird other than the cuckoo crossed your path from left-to-right, the animal itself symbolized good fortune for travelers. A right-to left passage, however, meant trouble.
They are all corvids.
Often, a flock of ravens is referred to as a “murder” rather than a “flock.” This is because of old English lore, which says that one or more ravens will accompany armies into battle and either fly down from the air to feed on corpses like the vultures in Rome’s Colosseum or they would get ahead of the army by flying over what might be an ambush site like Hannibal before crossing the Alps. If there was no ambush waiting at this location, then there would be none for when they arrive at their destination. For this reason, you may see ravens accompanying armies with banners or flags, and these communities that follow Carrion often call themselves a “murder.”