How Do Scientists Count Birds?

WHY IS THAT? Answering your kids' toughest questions

Katie Venit |

Get some binoculars and try counting the birds outside your home sometime. It might seem easy at first. You might see a couple of cardinals, maybe a crow. But then those birds fly away, and you see another cardinal. Is that the same cardinal as before, or is it a new one?

Now try to imagine how you would count all the birds in the world – migrating birds, nocturnal birds, backyard birds, desert birds. It seems impossible!

Ornithologists (scientists who study birds) know how hard it is to count every single bird, so they do their best to guess by counting the birds they see under certain circumstances.

Let’s say they want to count raptors (birds of prey). This can be difficult because raptors try to stay away from each other, so an ornithologist might only see one or two of them on a given day. However, during migration season, they tend to funnel together and follow the same routes. Scientists go to those routes and count the raptors they see there.

In the winter, bird counts record resident birds (birds that don’t migrate) and birds that traveled here for the winter, like juncos.

To do these counts, ornithologists rely on the help of citizen scientists, volunteers who help with research. The Christmas Bird Count, which began over 100 years ago, is the longest-running citizen science project in the world. In bird counts, people spread out over an area with a leader, and listen and watch for birds. Their records are entered into an online database. The counts are compiled, and ornithologists look for patterns. For example, they look to see how birds are being impacted by climate change, natural disasters, or human activities.

If you want to count birds this winter, there are plenty of chances. You can join in the Christmas Bird Count in December. In February, you can join the Great Backyard Bird Count, during which volunteers count the birds outside their houses. Beaver Creek Reserve will host a bird count on April 27 called the Spring Bird Count for Kids. Children go into the woods or watch the feeders and count the species of birds that they see.

Any of these activities are a great way to learn about birds and become a citizen scientist. They are also an excellent excuse to use binoculars.