The National Bird-Feeding Society assisted in a scientific study on Evening Grosbeak subspecies.  The study was performed in late summer 2010 by Aaron Haiman, a graduate student at the University of California, Davis. 

Aaron Haiman studied how many subspecies of grosbeaks exist, where they occur, and what the differences between them are.  Groups of birds were found throughout their range and banded, measured, recorded, and had blood samples collected from them. 

The first step in the project was finding the birds, and since they are nomadic this was challenging.  NBFS members were asked if they had Evening Grosbeaks coming to their bird feeders, especially if they were there regularly and for a while, and if so to contact Aaron.  Aaron had permits to band in California, Oregon, and Colorado and was looking for people and birds in those states. 

Participants were asked to:

• Contact Aaron when they had Evening Grosbeaks at their feeders
• Give an estimate on the number of grosbeaks visiting the bird feeders
• Give permission for Aaron to visit the feeders and band the Evening Grosbeaks