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Counting Nesting Birds

Every spring, I get excited as the birds start to return to Ontario from South and Central America. Life is emerging everywhere! Even though nature sometimes seems to conspire against them with cold snaps following sunny days, birds persist. Fire, rain, wind, predators, agricultural and industrial activities, cars, cats and inadvertent human disturbance all work to thwart this important annual breeding cycle. But they must breed, and they will, if they didn’t breed every year; there obviously wouldn’t be any birds! Studying the breeding behaviour, successes and failures of nesting species is an important activity because scientists can determine the health of the environment, both here and on their wintering grounds.

This year was the start of the 3rd Ontario Breeding Bird Atlas, and it will run until 2025. Wait a minute, what is an atlas? I thought that was a book of maps? Well, it sort of is, but in this context, an atlas is a form of ‘mapping breeding success’ over a period of time, following set protocols, where birds are the subject of interest.

This is an incredibly intensive breeding bird survey which will involve thousands of volunteers across Ontario, tens of thousands of volunteer hours and hundreds of thousands of bits of data. The participants will try to find every breeding bird in all of Ontario, during this 5-year study. The entire province is subdivided into bite-sized chunks, generally 10×10 km squares in the south and 100×100 km squares in the far north. This ensures concise coverage can be undertaken and impacts assessed, on a local basis, in a microcosm, rather than more broadly across all of Ontario, in a generalized manner.

Many organizations, such as: Birds Canada, the Canadian Wildlife Service (Ontario Region), Ontario Field Ornithologists, Ontario Nature and the Ontario Ministry of Natural Resources and Forestry will bring this project to fruition. Once the project is complete in 2025, a report will be prepared to celebrate its success.

This is the third such atlas. The first was undertaken during 1980-1985, and the second during 2001-2005. With this type of history, one can realistically compare how our birds are doing over a long period of time. Is development helping or hindering them? Which species are doing better? Worse? Unchanged? Are there trouble zones we could/should be protecting? So much can be learned from this citizen’s science project.

Breeding success will be defined in one of three categories: possible, probable or confirmed. Obviously, ‘confirmed’ is preferable, as it shows a species is definitely breeding in an area. Still, there is merit in the other categories, particularly for rare and hard-to-find species.

One of the risks of this intensive study is, some birds may inadvertently be negatively impacted, as zealous birders try to ‘confirm’ breeding. So please remember, the well-being of the bird is far more important than trying to find a nest! As noted above, the atlas has mechanisms built-in which are non-intrusive when it comes to trying to confirm breeding. If you do find a nest, it is always better to resist the temptation to look into the nest. Please don’t separate the vegetation for a better view, stand too close, be noisy or do anything else which might disturb the breeding birds! Just stand back, watch, listen and observe the behaviour. Usually, it will reveal what’s happening.

I am co-leading the Atlas project in Durham Region with Glenn Coady of Whitby, so, if you’d like more information, or more importantly, want to be a part of the birding team, which will do the study in Durham Region, please let me know, at No, you do not have to be an expert birdwatcher; you just have to be aware and ready to learn, to assist with this important project. Even if you just want to submit incidental findings, such as a nest on your property, please let me know, so the data can be recorded and entered into the provincial database. Every bit of data counts!

Geoff Carpentier is a published author, expedition guide and environmental consultant. Visit Geoff on-line at and on LinkedIn and Facebook.

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