Tree Swallow
(Tachycineta bicolor)


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

Widely distributed in Canada, the Tree Swallow is a familiar swallow of open fields, meadows, marshes, and other wetlands. The Breeding Bird Survey indicates a moderate decrease in its Canadian population since about 1970. Causes for this decrease are unclear. This species has been identified as a priority for conservation and/or stewardship in one or more Bird Conservation Region Strategies in Canada.


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
CanadaModerate DecreaseHighBelow Acceptable Level

Population estimate

Geographic area or populationPopulation estimate
Canada5,000,000 - 50,000,000 adults

Distribution maps


Migration strategy, occurrence

Short-distance migrant

Responsibility for conservation

Geographic areaResponsibility based on % of global population

General nesting period in Canada

Nesting period starts between early May and late 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 Tree Swallow is one of several species of aerial-foraging insectivores showing widespread declines in Canada. Causes of these declines remain unclear, but changes in aerial insect abundances have been suggested as one possible common factor, as well as changes in the ladnscape, insecticides, and climate change (Blancher et al. 2009, Nebel et al. 2010). However, a recent study in the Maritime Provinces suggests that the breeding success of Tree Swallows was not linked to insect abundance (Imlay et al. 2017). The Tree Swallow is a cavity-nester that uses natural holes in trees where available, but also readily accepts nest boxes. It may be negatively affected by reduced nest-site availability and/or competition with House Sparrows and European Starlings (Winkler et al. 2011).


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, NB -- Stewardship
Atlantic Northern ForestsAtlantic Northern Forests, sub-region and priority type: Atlantic, NS -- Other
Atlantic Northern ForestsAtlantic Northern Forests, sub-region and priority type: Quebec -- Stewardship
Boreal Hardwood TransitionBoreal Hardwood Transition, sub-region and priority type: Ontario and Manitoba -- Conservation
Boreal Softwood ShieldBoreal Softwood Shield, sub-region and priority type: Ontario -- Conservation