Birds took advantage of lockdowns by hanging out in the city, study finds

Warblers, hummingbirds, hawks and other migratory birds across Canada and the U.S. hung out in cities during the pandemic lockdowns in the spring of 2020, treating urban-dwelling humans to far more visits than usual, a new study finds.

Birding is a hobby that surged in popularity during the COVID-19 pandemic. And many birders logged the species they sighted, and their locations, through "citizen science" apps such as eBird that allow data gathered by volunteers to be used by scientists for conservation research.

The new study by Canadian and U.S. researchers compared birders' observations on eBird between March and May in the three years before the pandemic to those same months during the 2020 lockdowns, which coincided with birds' spring migration. It was funded by a grant from the Natural Sciences and Engineering Research Council of Canada targeted at pandemic-related research.

The researchers found big changes in which bird species in the study were spotted where. Of the 82 species tallied in the study, 66 of them changed abundance in counties where the level of traffic or human activity was altered. Most species increased in urban habitats, near major roads and airports and where there were stronger lockdowns, the study found.

"We also see with many species within cities themselves, that they moved from areas far from roads into areas closer to roads, for example," said Nicola Koper, a professor of conservation biology at the Natural Resources Institute at the University of Manitoba in Winnipeg. She's the senior author of the study, which also included researchers from Environment and Climate Change Canada, Cornell Lab of Ornithology, Carleton University in Ottawa and Dalhousie University in Halifax.

"That suggests that before the pandemic, a lot of birds were really being pushed out of the habitats that otherwise could have been suitable for them," she said, if it weren't for vehicle traffic and the noise and deadly collisions that come with it.

Bald eagles were one species that made very noticeable moves to counties with the biggest drops in traffic, Koper said. "They migrated in it using a different pattern in order to take advantage of the strongest lockdowns."