Bird watchers to survey Ontario’s feathered population for 3rd Breeding Bird Atlas


Volunteer bird watchers will be combing the province this year counting birds and looking for signs of nesting activity.

They’re contributing to data collection efforts for the third edition of the Ontario Breeding Bird Atlas 

The atlas helps researchers track bird populations and spot signs of species at risk, said atlas co-ordinator Mike Cadman, who has worked on all three of the books.

It can also help trigger conservation efforts. 

“It takes us five years to cover the whole province to give us as complete a picture as we can get of the distribution and abundance of all of the species that nest in the province,” Cadman said.

A new edition comes out approximately every 20 years.

Changes in bird populations noted between the first two editions of the atlas, compiled in the early 1980s and early 2000s, led to some species being deemed species at risk, which results in the development of a recovery strategy, Cadman said.

It also led to research into why, for example, aerial insectivores, such as swallows and swifts, had significantly declined.

A raven. (Vincent Bonnay/Radio-Canada)

How volunteers help

Organizers of the bird atlas collect their data by dividing the province into a grid system of 10-by-10-kilometre squares, Cadman explained. 

They seek volunteer birders to cover every one of the 2,000 squares in southern Ontario up to Sudbury and Sault Ste-Marie.

In northern Ontario, they use a sampling system that involves dividing the territory into 100-by-100 kilometre squares and sampling a percentage of the 10 by 10 squares within each of the larger areas, he said.

Volunteers working in the territory need to have sufficient expertise to identify birds by their appearances or their songs, Cadman said.

They do point counts in 25 random locations in their square, which consist of standing in one spot for five minutes and counting the birds that they come across. 

A blue jay feeding in a back yard. (Courtesy Canadian Bird Nerd)

They also search for signs of nesting activity — anything from the mere presence of a bird in its nesting habitat in nesting season to visible nests or fledglings or other types of evidence. 

“You can confirm breeding by things like distraction displays, like a killdeer will try to lead you away from its nest,” Cadman said. “So you don’t have to see the nest to know it’s there if it’s doing that.”

Despite the amount of work and the level of expertise involved in collecting the data, he said, finding volunteers to participate in the work is getting easier, thanks, in part, to social media.

Each of the partner organizations in the atlas, Birds Canada, Ontario Nature, the Ministry of Natural Resources and Forestry, the Canadian Wildlife Service and Ontario Field Ornithologists, also has their own network, he added. 

“We started promoting the project a few months ago, and we have, I think as of yesterday, 977 people were signed up to help with the work,” Cadman said.  “It looks like most of the squares north to about the cottage country have someone already interested in working in them.”

The project is still looking for more volunteers and Cadman said there are roles available for those without advanced skills in identifying birds.

Anyone interested in participating is asked to visit the Ontario Breeding Bird Atlas website. 



Leave a Reply

Your email address will not be published. Required fields are marked *