Natural Elements, NRCan's Monthly Newsletter

Bird Recognition Technology in Northern Forests

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Imagine you’re out for a walk in the woods. Could you recognize the song of a ruby-crowned kinglet or black-throated green warbler?

For researchers in the Ecosystem Impacts Division of Natural Resources Canada’s Great Lakes Forestry Centre (GLFC), part of the Canadian Forest Service (CFS), identifying the songs of forest birds is an important part of their work. It helps them to measure how bird populations respond to forest management, climate change and other factors.

Listening to Birds

New sound recognition software, coupled with new weather-resistant audio recorders, will soon allow researchers to identify birdsongs from recordings — particularly in the more remote forested regions of northern Canada.

The northern forests of Canada have a high diversity of bird habitats, and so are home to many species of birds — more than 300. And when that number is combined with the fact that bird population trends are constantly changing, bird monitoring and tracking become very challenging.

Usually, large-scale bird monitoring involves sending bird experts, often volunteers, into the field to listen to and identify birds. But since volunteers are lacking in remote areas of the boreal forest, and since the areas themselves are so vast, NRCan researchers have been looking to other solutions to assessing changes in the northern forest bird population over time.

Recently, NRCan has been exploring the use of remote audio recorders to monitor birds, with hours of recordings brought back to centralized stations for experienced bird call surveyors to listen to and identify species. “This process saves time and money, relative to having experts in the field at every survey,” says Lisa Venier, a GLFC research scientist.

Better Tracking, Less Time and Money

The process of recording birds in the forests begins by placing the specialized recording device — a Song Meter — in remote areas throughout the northern forests. The Song Meters are compact, weather-resistant and designed specifically for collecting recordings in unattended and remote locations. They are also relatively inexpensive and light-weight, and since they require minimum power they can record up to 90 hours on a single set of four regular flashlight batteries.

Further steps to improving the efficiency of bird monitoring will include computer and sound technology that can automatically identify the birds. So instead of having a researcher listen to hours of recordings to identify certain species, this new process could do most of the work, significantly reducing both the time and the cost of monitoring.

And thanks to these new recording methods, researchers can now easily review samples that gave seemingly incomplete or surprising results. “In many instances, the recordings have been used to identify errors in the field samples as well as errors in the interpretations of the birdsongs,” explains Steve Holmes, a GLFC research scientist.

The increased ability to effectively track birds, particularly in more remote locations, allows researchers to measure fluctuations in bird populations more precisely, keep more accurate and up-to-date inventories of birds on the Species at Risk lists and prioritize identified birds in conservation plans.

For more information about forest songbird research projects, visit the Canadian Forest Service Web site.