Bicknell's Thrush
(Catharus bicknelli)

Summary

Picture of bird
© Dan Busby
For additional photos and vocalizations, visit Dendroica. (Link opens in a new window.)

Bicknell's Thrush is one of the rarest songbirds in North America, with a highly fragmented breeding range that is restricted to northeastern North America. It was recognised as a distinct species in 1995, when it was taxonomically separated from the Gray-cheeked Thrush. Results from various surveys suggest a large decrease in the population of Bicknell's Thrush in Canada since 1970. Current threats to the population are high, and include habitat loss, climate change, predation and environmental contaminants (COSEWIC 2009b, Rimmer et al. 2001). It was assessed by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as Special Concern in 1999 but was revised to Threatened in 2009 (COSEWIC 2009b). This species has been identified as a priority for conservation and/or stewardship in one or more Bird Conservation Region Strategies in Canada.

Designations

Listing of the main designations for the species
DesignationStatusDateSubspecies, population
COSEWIC (Canada)Threatened2009 
SARA (Canada)Threatened2012 
IUCN (Global)Vulnerable 2012 
Partners in Flight (North America)Stewardship List, Watch List Species2012 
Wild Species (Canada)At Risk2010 
Partners in Flight (Tri-National Vision)High Tri-National Concern2012 
Bird Conservation Region StrategyPriority Species2013 

Population status

Geographic areaStatusReliability
CanadaLarge DecreaseMedium
 

Population estimate

Canada5,000 to 50,000 adults
 

Distribution maps

 

Migration strategy, occurrence

Long-distance migrant

Responsibility for conservation of world population

CanadaModerate

Conservation and management

Bicknell's Thrush presents a significant challenge to wildlife managers, researchers and conservation organizations. It is secretive and occupies remote and inhospitable habitats which make field surveys difficult. It winters exclusively in the Greater Antilles, primarily in the Dominican Republic, where habitat loss has been substantial and is thought to be a significant limiting factor (McFarland et al. 2008). Further threats come from habitat modification due to climate change (McFarland et al. 2008) and high moose populations in parts of its range, red squirrel predation (COSEWIC 2009b), habitat loss and fragmentation (McFarland et al. 2008), and contaminants in high elevation habitats (McFarland et al. 2008). Forestry practices have mixed effects on the species. Dense new coniferous growth following logging can benefit Bicknell's Thrush, but later pre-commercial thinning reduces the quality of the breeding habitat. A Conservation Action Plan has been published by the Bicknell's Thrush International Conservation Group. For information on the legal status of this species under the Species at Risk Act (SARA) and to view available Recovery documents, see the SARA Registry.

 

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
Atlantic Northern ForestsAtlantic Northern Forests, sub-region and priority type: Atlantic Region - New Brunswick
Atlantic Northern ForestsAtlantic Northern Forests, sub-region and priority type: Atlantic Region - Nova Scotia
Atlantic Northern ForestsAtlantic Northern Forests, sub-region and priority type: Quebec Region
Boreal Hardwood TransitionBoreal Hardwood Transition, sub-region and priority type: Quebec Region
Boreal Softwood ShieldBoreal Softwood Shield, sub-region and priority type: Quebec Region
 

References