The Economic Times

In 1880, teacher Wells Cooke began writing down when migrating birds arrived; 90 years later, the project had left millions of records scientists still use today

Wells W. Cooke began recording bird migration dates in 1880 using index cards and a network of volunteers. This initiative expanded into a national program that operated until 1970, collecting millions of data points. Recent research has utilized this historical data to understand how climate change has impacted bird migration patterns. Studies indicate birds are migrating earlier in spring due to warming trends.