Breeding Bird Survey Results
This website provides detailed population trend information based on data collected through the North American Breeding Bird Survey (BBS), for approximately 300 Canadian bird species. The trend results presented here are Canadian trends and thus use data from Canadian BBS routes only. Results are updated annually. Trends are presented for species, provinces, territories and Bird Conservation Regions for which there are sufficient BBS data for statistical analysis.
The BBS is jointly coordinated by Environment Canada and the U.S. Geological Survey (USGS), Patuxent Wildlife Research Center. Any use of these BBS results for Canada should acknowledge the hundreds of skilled volunteers in Canada who have participated in the BBS over the years and those who have served as provincial or territorial coordinators for the BBS.
Please visit the Status of Birds in Canada web site for a comprehensive assessment of the population and conservation status of most species that breed in Canada, which considers BBS results as well as results from other relevant surveys. For waterfowl, comprehensive assessments are available in the most recent report on the Population Status of Migratory Game Birds in Canada.
Changes to the Analysis for 2012 Results
In an effort to continually improve the population trend estimates from the BBS, since 2011, the results have been produced using a Bayesian hierarchical analysis. This new approach provides more precise trend estimates that are less sensitive to sampling error, and provides more intuitive measures of uncertainty.
In 2012, a small change was made to the minimum data criterion for including geographic strata in the analysis for a given species. Strata are now included in each species’ analysis if they contain at least 3 routes on which the species was observed and at least one of those routes was surveyed for 5 or more years. In the 2011 analysis, the criterion required at least 3 routes on which the species was observed and an average of 2 survey-years per route. This new criterion ensures that once a stratum has met the threshold, it will remain in the analysis in following years. However, users should note that because of the change, the strata included in the analysis have changed between the 2011 and 2012 analyses for some species. In these cases, the national trend estimates may have changed because they represent a different portion of the species’ population and geographic range.
In addition, the estimates of geographic coverage were recalculated using updated species range-maps. Users should note that changes in coverage estimates between the 2012 and the 2011 analyses reflect the updated range maps and not a major change in the geographic scope of the survey.
Visit BBS Statistical Methods for more information on the statistical methods used to produce these trends, annual indices and credibility measures, and contact BBS@ec.gc.ca for a detailed analysis of the differences between the new statistical analysis and the previous analysis used to estimate trends before 2011.
View Trends and Annual Indices
- View Breeding Bird Survey trends by selecting a Species
- View Breeding Bird Survey trends by selecting a Geographical Region
Download all Trends and Annual Indices
Select a link below to download all Breeding Bird Survey trend results or annual indices as comma delimited text files. Note: Similar files specific to a given species or region are available for download through the View Trends and Annual Indices options above.
- Download trend results for all species, regions and time periods (*.csv, 3.8 MB)
- Download annual indices for all species, regions and time periods (*.csv, 38.3 MB)
Please send enquiries about the Breeding Bird Survey in Canada to: BBS@ec.gc.ca
- Date modified: