Historical Bird Migration Card
![Image: Historical Bird Migration Card](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/1_Mill_Card_Final_-1-.jpg?itok=V716_e5m)
Detailed Description
Image scan of a historical bird migration card (1904). This is just an example of the more than 6 million handwritten cards stored in government files, in the North American Bird Phenology Progam, with more than a century of information about bird migration, a veritable treasure trove for climate-change researchers because they will help them unravel the effects of climate change on bird behavior.
This card: House Wren
Sources/Usage
Public Domain.