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Glebe Report September 2023
Corvids such as ravens and crows are among the smartest animals in the world.
Corvids – the smartest birds around
By Jeanette Rive
I was alerted to our local raven family by the sounds from the top of the Lord Lansdowne building – “kraaah” “brronk” “croak” “cling” as they called to each other. Then the whole family flew down to nearby trees, creating an unmistakable ruckus.
At about the same time, a rubber crow was also making a ruckus in Ottawa. The new art installation along the bicycle parkway near the Pimisi LRT station at Lebreton Flats provoked a discussion about the relevance of street art. It’s a five-metre-long sculpture of a crow made from recycled tires by PEI artist Gerald Beaulieu, and it makes a strong statement about our environment and our relationship to the natural world.
The American crow and the Common raven, both part of the corvid family, are among the smartest animals in the world. Crows are widespread over North America. The Common raven, despite its name, is not that common and is usually seen in more northerly areas. As more areas are rewilded in conservation efforts, more ravens are being observed. Other birds in the corvid family include rooks, magpies, jays and jackdaws. Their brain to body mass is equal to that of non-human animals such as great apes and cetaceans, and it is said they have the intelligence of a chimp. Crows can recognize faces, have been known to leave little gifts for those who fed them and can even communicate information about their interactions with humans to others.
Crows and ravens (like parrots and mynah birds) can mimic human words and animal sounds due to the design of their syrinx (the avian equivalent to human vocal folds) which allows air to pass through it, making it vibrate to
produce sounds. Some have learned to mimic up to 100 words! Ravens are considered good at problem solving, such as making tools to extract food and advance planning. Some crows’ nests in Rotterdam in the Netherlands were recently discovered to be constructed almost entirely from long strips of metal spikes found on buildings to deter pigeons and other birds from roosting there. It is surmised that these nests would deter predators from eating their eggs or hatchlings.
How do you tell the difference between a crow and a raven?
Size: Ravens are considerably larger than crows, measuring about 65 cm from head to tail feathers versus 40 to 50 cm for crows. The raven also weighs about twice as much, up to two kilos.
Appearance: Ravens are glossier. Their feathers show iridescent colours and are fluffier and more dishevelled around their heads. The head shape and bill shapes are different: the crow’s bill is more pointed; the raven’s is thicker and more curved. The raven’s tail is fan-shaped when open; the crow’s is wedge-shaped. In flight, ravens soar while crows flap
their wings. Ravens can even fly upside down and do aerial somersaults! On the ground, crows walk while ravens hop.
Social life: In Ottawa, large flocks of crows have been seen flying at dusk heading to a common destination. Crows congregate in large numbers, from a few hundred to up to a million, to sleep in communal roosts. This may be for safety reasons or to keep warm in winter. Crows travel and forage in small groups, often one family comprising several generations. One-yearold juveniles remain with the family to help raise the next generation. Young corvids can be quite playful, passing sticks to each other or playing a bird form of “follow the leader.” They have also been filmed sliding down a snowy roof on a plastic lid! Ravens are usually seen in pairs outside breeding season. Neither species migrates although some crows do try to escape our winters.
As with many mammals, research has shown that crows mourn their dead, holding a form of funeral and wake. When a crow finds a dead spe cies mate, it calls out to others in the area and they gather around nois ily, possibly transferring information
about potential threats or predators. Many years ago in Asia, our house cat caught a crow and was triumphantly carrying it into the house, followed by a flock of crows loudly bombarding it. The corpse was quietly disposed of, but the crows stayed around uttering threats to the cat!
Crows are often hated or just tolerated because they are considered a nuisance. However, they do help farmers by eating pest insects. For many people, both ravens and crows have important religious or spiritual meaning. Legends and stories are found in cultures from Norse mythology to the legends of Indigenous peoples. In Haida stories, the raven often plays the role of the Trickster, symbolizing intelligence, cleverness and creation, combining characteristics of good and evil. Even though many associate the crow with a bad omen, Native Americans see the crow in a positive light as a symbol of good luck and wisdom.
Crows and ravens are extraordinary creatures to be admired for their unique qualities and intelligence.
Jeanette Rive is a Glebe bird enthusiast and frequent Glebe Report contributor.
