| Species: Common Raven
Corvus corax
Description:
The Common Raven is
a majestic bird that prefers wild open areas but makes occasional
forays into urban settings. More often heard than seen, the image
this bird conjures to one’s mind is wilderness: open woodland in
winter and the distinctive croak call of the raven in the distance.
It is known for its
high intelligence and numerous anecdotes of its cleverness at
procuring food such as stealing an ice-fisherman’s catch.
This species has a
cosmopolitan holarctic distribution. In North America its
distribution ranges from the Arctic tundra south to Nicaragua.
Identification:
General: It
is the largest passerine in North America with a length up to 69
centimeters and a mass ranging from 689 to 1625 grams. Plumage is
all-black, throat-hackles prevalent, a robust bill and that
distinctive call “quork”. They have a tendency to soar during flight
and revealing the wedge-shaped tail.
Adult Male:
Similar to the female but may be larger.
Adult Female:
Similar to male but may be smaller.
Juvenile:
Possess similar plumage to adults but is duller. Eyes have a
blue-gray iris compared to the dark brown iris of adults.
Similar Species:
The Northwestern Crow and other crow species are smaller and more
gregarious. The wedge-shaped tail identifies the raven from its
smaller crow cousins during flight. The Chihuahuan Raven is smaller
but slightly larger than the American Crow and its distribution is
from southwestern US to northern Mexico.
Behavior:
They often travel in pairs and make frequent contact calls to each
other. Younger birds may flock and where food is concentrated ravens
may form larger groups. Their resourcefulness and observed play
behavior have endeared them to some observers.
Habitat:
Ravens prefer less spoiled habitats compared to crows. They can be
found in forests, rocky cliffs, scrubland and most other habitats in
their range except for tropical rainforests.
Information:
The Common Raven is
divided into 8 recognized subspecies across its range. Corvus corax
principalis is the subspecies encountered in northern North America
and Greenland. C c sinuatus is another North American subspecies
that occurs in south central US and Central America. It is
distinguished from its northern cousin by its smaller size.
They are generally
year round residents throughout their range but populations that
face extreme conditions like the Arctic winter may make seasonal
movements.
Ravens tend to form
life long pairs where courting starts at a young age but may not
bond for another 2 or 3 years. Infidelity has been documented from
this normally monogamous species. Most clutches are started between
March or April where 3 to 7 eggs are laid and are incubated by the
female. Nestlings fledge between 5 to 7 weeks of age but may stay
with their parents for another six months. They are long-lived birds
and have been recorded to live more than 13 years in the wild. In
captivity, they can live as long as 80 years.
Ravens and their
nests are seldom preyed upon. Ravens will be highly territorial and
will aggressively defend against predators. Potential nest predators
include marten, large owls and other raptors, coyotes and other
ravens. Their intelligence predisposes them to be cautious when
approaching novel carrion. They will wait until other scavengers
such as crows and jays have tested the carcass. Sometimes another
carnivore like the Gray Wolf would be called to help dispose of a
carcass.
Raven has been a
prominent figure in the mythology of many indigenous North American
cultures especially among the Pacific coast. In Coast Salish
creation cycles the islands off BC’s coast were formed from the mud
that fell off of Raven’s bill and feet. In Haida, Raven encouraged
the First Peoples to leave a clam shell. In Tlingit, Raven’s cunning
outsmarted a Chief who selfishly imprisoned the sun for himself.
Conservation
Status: (Least Concern)
Ravens have been
branded crop raiders and livestock predators by some and have been
persecuted. There have been regional extirpations due to habitat
loss and hunting but ravens are in no danger of extinction. In other
parts of their range they have increased thanks to human influence
ie 16 X from their original population over 25 years in the Mojave
Desert. There is a concern that the Common Raven could endanger the
recovery of certain species at risk such as the Marbled Murrelet and
Steller’s Eider.
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