|Species: Northwestern Crow
are among the most ubiquitous birds in the urban environment
particularly along the western coast of North America from Alaska to
They are readily
identified from their entirely black plumage, gregarious habit and
their high-pitched “caw” with which they sometimes call with
seems to form part of a species complex with the very similar
American Crow, but it concentrates more in intertidal habitats.
Urbanization from the early twentieth century onwards has been good
for this species.
Like most other Corvids, Northwestern Crows tend to be larger than
other passerines with glossy black plumage. It possesses long legs
and a sturdy bill. Adults weigh between 340 g to 440 g and measure
between 33 cm to 41 cm in length.
Similar in plumage to the female but slightly larger in body size.
Older individuals in breeding condition can be sexed in-hand for
Similar in plumage to the male but slightly smaller in size. Older
individuals in breeding condition will have a brood patch.
Birds less than 3 months would have looser and fluffier feathers of
a dull black color and their eyes are blue instead of the brown-gray
of adults. Those aged 3 to 15 months share with adults the black
plumage but with less iridescence.
Very similar to the more inland American Crow (Corvus
brachyrhynchus) but can be distinguished by its smaller feet and
more slender bill. Its call is also more resonant. It is also
smaller than the less social Raven (Corvus corax).
Often seen in groups poetically termed a “murder of crows”. Flocks
can be observed flying to their roosts as evening approaches. While
foraging on the ground they will either hop or walk. Sometimes they
follow people in the hopes of scoring on a tidbit.
common visitor to residential lawns and other urban habitats it is
also at home in more naturalized areas. Its original habitat is
along the shorelines and beaches.
BC is considered to
support most of the global population of this species. Northwestern
Crows like many Corvids demonstrate intelligent and opportunistic
behavior. These traits have earned them both derision and
Its reputation as a
nest predator and habit of bullying and preying on smaller birds and
other vertebrates has given it the label of varmint among historical
records. It has also been accused of tearing up the sod of lawns in
its foraging for earthworms and grubs and raiding crops.
All social species
like the Corvids develop a kind of intelligence that humans tend to
identify. A demonstration of its social intelligence is the
observation of mobbing behavior towards predators such as raptors.
It is not
considered migratory but it will leave from exposed to more
sheltered areas near human habitation during winter. It is a
year-round resident in British Columbia.
They breed from
March to July and typically nest in trees or shrubs along forest
edges close to the ocean. The female incubates the eggs for about 18
days. At this stage the pair becomes protective and territorial and
they can be bold enough to attack human passersby. A pair might even
retain a helper from a previous brood that will assist in feeding
and protection of its younger siblings. Not normally considered a
colonial nester, groups of 2 – 19 pairs have been recorded in BC.
Past research has
indicated a 57% success rate for nests to fledge at least one young
which is usually about 31 days after hatching. Parents will still
feed their young until they are at least 77 days old. A fledged bird
can expect to live as long as 12 years in the wild.
Status: (Least Concern)
It has a fairly
stable population in recent years, but it has shown a substantial
increase compared to records from the early twentieth century. Where
its range is sympatric with the American Crow, hybrids have been
reported but not confirmed. Unique features of this crow could be
lost through genetic swamping if the American Crow expands its
range. Nevertheless, the Northwestern Crow’s catholic diet and
cleverness has enabled it to be among the few species able to cope
with anthropogenic disturbances to its natural habitat.