Background information

Bird population estimate

 

Landbirds

Landbird Population Categories
Landbird Population Categories
(includes breeding birds only)
< 50 adults
*only used if sufficiently detailed information is available.
< 500 adults
*only used if sufficiently detailed information is available.
< 1000 adults
*only used if sufficiently detailed information is available.
< 5,000 adults
5,000 - 50,000 adults
50,000 - 500,000 adults
500,000 - 1,000,000 adults
1,000,000 - 5,000,000 adults
5,000,000 - 50,000,000 adults
> 50,000,000 adults

We extracted the majority of landbird population estimates from the 2019 Partners in Flight (PIF) Population Assessment Database (PIFa 2019), and the Avian Conservation and Assessment Database (PIFb 2019), which were generated by the PIF Species Assessment Process and were companions to PIF’s Landbird Conservation Plan (Rosenberg et al. 2016) and the State of North America’s Birds report (NABCI 2016). We placed them into the broad categories seen above to account for uncertainty in these estimates. We sourced a small number of population estimates from species at risk assessments, expert opinion, and other documentation. See the complete Species Assessment Database to learn more about the methods used to calculate the population estimates.

 

Shorebirds

Shorebird Population Categories
Shorebird Population Categories
(includes birds breeding and migrating within Canada)
< 50 adults
*only used if sufficiently detailed information is available.
< 1,000 adults
1,000 - 10,000 adults
10,000 - 50,000 adults
50,000 - 500,000 adults
500,000 - 1,000,000 adults
> 1,000,000 adults

Environment and Climate Change Canada experts derived the population size estimates based on Andres et al. (2012), and updated with published or unpublished information where available. For each species, the estimates include all populations breeding within Canada as well as numbers estimated to pass through Canada on migration if the breeding grounds lie outside Canada, i.e., the total number of that species estimated to use Canada. For breeding populations, these continental estimates were then converted to population estimates for Canada using relative abundances estimates when available, estimated proportion of the range in Canada or expert opinion.

 

Seabirds and Waterbirds (not including waterfowl)

Seabird and Waterbird Population Categories
(includes breeding adults only except for seasonal visitors, which may include adults and juveniles)
Not yet available
0 adults
< 100 adults
100 - 500 adults
500 - 1,000 adults
1,000 - 10,000 adults
10,000 - 25,000 adults
25,000 - 50,000 adults
50,000 - 100,000 adults
100,000 - 200,000 adults
200,000 - 300,000 adults
300,000 - 400,000 adults
400,000 - 500,000 adults
500,000 - 600,000 adults
700,000 - 800,000 adults
1,000,000 - 2,000,000 adults
2,000,000 - 3,000,000 adults
3,000,000 - 4,000,000 adults
6,000,000 - 7,000,000 adults
> 10,000,000 adults

Environment and Climate Change Canada (ECCC) staff revised the population estimates of regional seabird and waterbird populations in 2018 using published and unpublished information. These regional estimates were summed to determine the population estimate for Canada. Final estimates were reviewed by ECCC’s Waterbird Technical Committee. For colonial-nesting species, population estimates were derived from colony counts of nests or breeding pairs conducted during the nesting season. For other waterbirds, population estimates were derived from information obtained through dedicated monitoring protocols (e.g., acoustic sampling for elusive marsh birds and counts at migratory staging areas).

 

Waterfowl

Waterfowl Population Categories
Waterfowl Population Categories
1,000 - 10,000 birds
10,000 - 25,000 birds
25,000 - 50,000 birds
50,000 - 100,000 birds
100,000 - 500,000 birds
500,000 - 1,000,000 birds
1,000,000 - 5,000,000 birds
5,000,000 - 10,000,000 birds
> 10,000,000 birds

We extracted the waterfowl population estimates from the 2017 Population Status of Migratory Game Birds in Canada report (Canadian Wildlife Service Waterfowl Committee 2017) whenever possible. These estimates were obtained during waterfowl aerial surveys conducted mostly during the breeding season and on the staging and wintering areas. We extracted global population estimates from the North American Waterfowl Management Plan (NAWMP Committee 2018). View the Population Status of Migratory Game Birds in Canada reports for more information.

References