The Crossbill Project

Red Crossbill © Jens Halbauer

Purpose is to provide a stable, long-term home for Crossbill research over a broad front: field observations, recordings, assortative mating and call type delineation by sound, range and DNA. Provide information to the scientific community on the validity of call types and potential full-species separations for flight call types, geographically isolated populations (old world versus new world) etc. One purpose would be to serve as arbiters of flight call determination via audiospectrographic analysis and machine learning/AI for this worldwide complex.

Whether it’s through loving birds and getting in the field to watch our feathered friends, the easiest and best way to be a part of this collaborative network is that whenever you’re the field and you hear crossbills, especially if you’re in Canada or somewhere across the Western Palearctic where recordings are scarce, is please grab a recording, whether with professional gear or phone, and upload it to Xeno Canto, BirdNet or ideally Macaulay Library! Macaulay Library has over 10,600 crossbill recordings making it the most common species in the collection by almost 50%, and that is thanks to all of you!

We are planning to fund student research projects. And lastly, we implemented an ARU component of The Crossbill Project this past summer, and if you’re interested in helping in the future, please contact us as well.

Get in touch:
If you would like to know more about or want to contribute to this project, please get in touch with Matt (NA) or Patrick (WP)

Check out our latest Call for Action

Please upload your sound recordings:
-> Xeno Canto
-> BirdNet
-> Macaulay Library

Learn more about the Crossbill Recognition Model:


-> Parrot Crossbill

-> Scottish Crossbill

-> Red Crossbill (NA)

-> Red Crossbill (WP)

-> Cassia Crossbill

-> White-winged Crossbill

-> Two-barred Crossbill

-> Hispaniolian Crossbill