Effects of Climate Change on Bird Migration in Concord

By Amanda Gallinat and Richard B. Primack

 

“I would thus from time to time take advice of the birds.” Henry David Thoreau in his Journal.

 

From 1851 to 2007, dedicated birders in Concord, including Henry David Thoreau, Ludlow Griscom, William Brewster, and Rosita Corey recorded first-bird sightings—when bird species are first spotted returning in the spring. Analyzing this data revealed that while migratory birds arrive earlier in warmer years, their overall response to climate change is much weaker than that of plants and insects.

 

Photo 1: Observers recording birds at Great Meadows Wildlife Sanctuary.

Recently we spoke to the Nuttall Ornithological Society about the statistical challenges of combining the past records made by a handful of individual observers with the Concord eBird data from 2013-2022 contributed by hundreds of local observers.

Do these eBird records reveal that birds are arriving earlier now? Or are birds arriving at the same time as in the past, but having more observers allows them to be detected sooner? This is what our team is currently investigating. We hope to discover an answer.

 

Photo 2: Richard and Amanda at the Nuttall meeting.

 

Thanks to the Nuttall Club for hosting us and asking lots of thoughtful questions! And thanks to team members Abe Miller-Rushing, Libby Ellwood, Trevor Lloyd-Evans, and Corey Callaghan.