Keep listening for Cassia Crossbills

[Nathan Pieplow]

Hello all,

I wanted to alert you that I've recently received confirmation that Cassia Crossbills have been recorded in at least two additional counties in the past couple weeks (Park and Eagle). JoAnn Potter Riggle had them at Sylvan Lake State Park in Eagle County on Aug 4 (https://ebird.org/checklist/S116272355), and I had one bird mixed with Red Crossbills between the Michigan Creek Campground and Georgia Pass in Park County on Aug 6 (https://ebird.org/checklist/S116465298). Both of our recordings have been confirmed by Matt Young and Tim Spahr of the Finch Research Network.

This brings to four the number of counties where Cassia Crossbills have been recorded (this year: Eagle, Park, Summit; last year: Grand). All four sites are within approximately a 20-mile radius of the Alfred Bailey Bird Nesting Area. However, I suspect that the Cassia invasion is more widespread, and if people record every crossbill they hear, we'll probably find more Cassias in new places. Rachel Hopper's been looking in Larimer and I've done a little looking in Boulder County, but I wanted to encourage more people to actively look in more areas. Keep an eye on those lodgepole pine stands!

Nathan Pieplow

Boulder