The Colorado Field Ornithologists Annual Convention, July 19-23, 2023

I picked up Cliff Hendrick at 6 AM, July 19, 2023, and we headed to the Mount Evans auto road, a two-hour drive from Fort Collins. This road is the highest paved road in North America, reaching the peak of Mt. Evans above 14,000 feet. We paid $2 for admission, taking advantage of Cliff’s senior discount to federally managed parks. We scouted the area around Summit Lake where I would return with a field trip a few days later. Bird diversity is low at high elevation. All we observed here was American Pipit, Brown-capped Rosy-Finch and a distant White-tailed Ptarmigan. We also checked the forests at the lower elevations for Cassia Crossbill without luck.

One of the principal bird targets of the Convention field trips was Cassia Crossbill, formerly known as Red Crossbill type 9. This population was elevated to species status in 2016 after biologists determined that they were sufficiently distinct from other crossbill populations. Birders in the field can distinguish them from the other 11 North American crossbill types by their unique flight call. Otherwise they are identical. Up until last year, Cassia Crossbill was only known from the Lodgepole Pine forests of Cassia County and a couple of neighboring counties in southern Idaho. They were thought to be the only sedentary crossbills in the US. Other crossbills are nomadic, roaming the forests of the continent for consumption of cone crops. Each crossbill subtype is adapted for a different type of cone. 

In 2021, Christian Nunes recorded the flight calls of a small group of crossbills in Grand County, CO, in the mountains northwest of Denver. He sent the recordings to crossbill vocalization expert Matt Young to determine the types of Red Crossbill that were present. To Christian’s surprise, Matt told him they were Cassia Crossbill, which had never before been reported in Colorado. It isn’t every day that you discover a new bird species for your home state. I have been birding avidly in Colorado for close to three decades and have not had the honor of discovering a new state bird yet. 

The next summer, Eric DeFonso was conducting bird surveys in Summit County, Colorado, and found more Cassia Crossbill. This summer, Eric discovered Cassia Crossbill in Gunnison County. Confirmed EBird reports began turning up throughout the Colorado mountains. Nathan Pieplow, author of the Peterson Field Guide to North American Bird Sounds, reviewed some of his crossbill recordings from Colorado and discovered that Cassia Crossbill has been in Colorado for at least ten years!

On the first day of the CFO convention, Chris Wood co-led a field trip to the William M. Bailey Bird Nesting Area in Summit County to search for Cassia Crossbill. This was the site where Eric DeFonso detected them in the summer of 2022. The conference organizers, including myself, were thrilled to hear Chris’s report that he had found the birds in the same spot as 2022!  This was great news because several field trips had been scheduled to search for the species but recently reported birds in Gunnison and Chaffee counties were too far away from the convention venue in Summit County for the field trips to pursue. The crossbills found by Chris were less than an hour away. 

The Convention was four days long and I led or co-led a field trip each morning. On July 20,  I led a posse to Park County. Highlights were Mountain Plover, Prairie Falcon and a large flock of Type 4 Red Crossbills. On July 21, I co-led (with Chris Wood) the Mount Evans field trip. Brown-capped Rosy-Finch and mountain goats stole the show. On July 22, it was my turn to search for the Cassia Crossbill for a group of about 20 conventioneers. Unfortunately we were unsuccessful in our quest. On July 23, I co-led (with Rebecca Weiss) a contingent to Jackson County. Highlights included a family of Greater Sage-Grouse, nesting Red-necked Grebe and an unexpected American Bittern. At 3:00 PM, Rebecca led most of the group back to the convention center at Copper Mountain Resort. I continued the field trip a few more hours, exploring the Laramie River valley of Larimer County. Two birders joined me: Cliff Hendrick of Fort Collins, CO (who had also birded with me in January in Puerto Rico and South Florida in May) and a visiting Israeli birder, Yaron Charka. Highlights were a pair of White-winged Crossbill (photographed by Yaron) and a migrating male Calliope Hummingbird (Biggest Year-Bird number 727). 

This convention was held jointly with Western Field Ornithologists. Chris Wood and Jesse Barry were invited speakers and they each gave fabulous presentations about community participation in birding and science through the use of eBird and Merlin mobile apps, respectively. Although my second and final two-year term as CFO President had ended in June, I still had numerous responsibilities at the Convention. With the conference completed, this was one less distraction impeding my progress for my USA and Territories Big Year. I asked Chris Wood if eBird could establish a new “major  region” comprising the fifty states and outlying territories of the USA. He said he would pass the suggestion on to the eBird team. Shortly afterward, Marshall Iliff contacted me and said they would consider creating this category.  Once established, tracking list totals for “USA and Territories” will be easy using eBird.