Photo: Simon Pierre Barrette

Bird atlases use data collected during a given period to map the presence and, increasingly, the relative abundance of birds occurring within a set area. Because they monitor bird populations and can be repeated over time, bird atlases provide a valuable tool for bird conservation.

More often than not, bird atlases focus on the distribution of birds during the breeding season, and these are referred to as Breeding Bird Atlases. Atlases typically cover a large area (e.g., a country, a province or a state) that is subdivided into smaller units, which can vary in size depending on the scale of the project. In Canada, bird atlases use 10-km survey squares (100 km2), and data are typically collected over a five-year period.

The aim of participants of the Québec Breeding Bird Atlas is to find breeding evidence for as many bird species as possible within each 10-km2. Atlassers who feel confident about identifying birds by song are also encouraged to conduct point counts to allow the relative abundance of the species present to be determined. The data collected will serve to 1) map the distribution of each bird species nesting in Québec and 2) to map the relative abundance of certain of these. The relative abundance maps are particularly valuable for conservation because they identify the areas where a given species is more abundant, as well as areas where it is less so.