Ontario Breeding Bird Atlas (2021-2025): special surveys

Project name: Ontario Breeding Bird Atlas

Goals : The atlas represents an enormous coordinated effort by thousands birders who surveyed the province from Lake Erie to Hudson Bay. It summarizes the state of all Ontario breeding birds, including information on each species' biology and abundance. Special sections analyze changes in bird populations and distribution, indicating which species are most imperiled and which are thriving.

Dataset summary : Ontario Breeding Bird Atlas (2021-2025). Includes general atlassing checklists, point count data and special surveys (e.g. Nocturnal Owls, Marsh Birds), and summary of the highest breeding evidence reported by square and year for all species. This project represents the third atlas in the province, with the goal to allow an evaluation of changes in population levels and distribution.

Year started : 2021

Year finished : 2025

Season(s) and frequency : Breeding season, depending on the species.

Geographic area covered : Ontario

Primary species covered : All breeding bird species

Sampling Design : https://www.birdsontario.org/instructions/

Field methods : https://www.birdsontario.org/instructions/