Northwestern Crow
(Corvus caurinus)

Summary

Picture of bird
© Jukka Jantunen (flickr.com/photos/jukka_jantunen)
For additional photos and vocalizations, visit Dendroica. (Link opens in a new window.)

In Canada, the Northwestern Crow is restricted to the coast of British Columbia. It is very similar to, and often considered a subspecies of, the American Crow, from which it differs in its smaller size and lower pitched call (Verbeek and Butler 1999). The Northwestern Crow adapts well to urban and rural habitats, and results from the Breeding Bird Survey and the Christmas Bird Count suggest little overall change in numbers since the early 1970s. This species has been identified as a priority for conservation and/or stewardship in one or more Bird Conservation Region Strategies in Canada.

Designations

Main designations for the species
DesignationStatusDateSubspecies, population
IUCN (Global)Least concern2018 
Wild Species (Canada)Secure2015 
Bird Conservation Region StrategyPriority Species2013 

Population status

Geographic area or populationPopulation change relative to ~1970ReliabilityStatus in relation to goal
CanadaLittle ChangeHighAt an Acceptable Level
 

Population estimate

Geographic area or populationPopulation estimate
Canada50,000 - 500,000 adults
 

Distribution maps

 

Migration strategy, occurrence

Resident

Responsibility for conservation

Geographic areaResponsibility based on % of global population
CanadaHigh

General nesting period in Canada

Nesting period starts between mid-April and early May and ends between mid-July and late July, depending on the region. Before or after this period, the probability of an active nest is lower.
 

Conservation and management

The Northwestern Crow formerly foraged primarily on shoreline environments such as tidal flats and rocky shores. Forest clearing along the coast and rivers has allowed an expansion of its historic range (Verbeek and Butler 1999). An adaptable species, the Northwestern Crow now feeds extensively in human-altered environments as well, including landfills and suburban gardens (Verbeek and Butler 1999). Large urban roost sites, at least one of which numbers about 16,000 birds, are often considered nuisances by local residents (Verbeek and Butler 1999). Recent studies have identified high concentrations of beak deformities in Northwestern Crow's from Alaska to British Columbia and into Washington though the cause and potential effects on populations are not known (Van Hemert and Handel 2010).

 

Bird conservation region strategies

Environment and Climate Change Canada and partners have developed Bird Conservation Region Strategies in each of Canada’s Bird Conservation Regions (BCRs). In these strategies, selected species are identified as priorities for one or more of the following reasons:

  • conservation concerns (i.e., species vulnerable due to population size, distribution, population trend, abundance, or threats)
  • stewardship responsibilities (i.e., species that typify the regional avifauna or have a large proportion of their range or population in the sub-region)
  • management concerns (i.e., species that require ongoing management because of their socio-economic importance as game species, or because of their impacts on other species or habitats)
  • other concerns (i.e., species deemed a priority by regional experts for other reasons than those listed above or because they are listed as species at risk or concern at the provincial level)

Select any of the sub-regions below to view the BCR strategy for additional details.

BCRs, marine biogeographic units, and sub-regions in which the species is listed as a priority
RegionSub-region and priority type
Northern Pacific RainforestNorthern Pacific Rainforest, sub-region and priority type: Pacific and Yukon -- Stewardship
 

References