Date: 7/8/19 12:19 pm From: Eric DeFonso <bay.wren...> Subject: [cobirds] Grace's Warbler, Costilla County (private ranch)
While doing a survey for the Bird Conservancy on a private ranch near Fort Garland in Costilla County this morning, I heard and recorded a Grace's Warbler at around 9200' in an area of mixed ponderosa pine/Douglas-fir habitat with a fairly developed understory of sage and serviceberry. It caught me quite by surprise and unfortunately the bird was not close by, but I did manage a fairly lousy recording of it from a range of about 70-100 meters (I'm guessing). Based on past experience with this species I knew it would take a while to visually locate, and unfortunately I was still in the middle of my scheduled survey and needed to stay on time since I was on private property. But I think my recording will confirm its identity, as the spectrogram of the sound matches GRWA exactly and rules out other (somewhat) sound-alikes like Dark-eyed Junco, Chipping Sparrow, and Virginia's Warbler.
According to eBird, there are currently no accepted records of GRWA in Costilla County, and the Colorado County Birding page currently does not include GRWA on its Costilla checklist. However, the site for this bird is only about 25 miles from Spanish Peaks SWA and its known GRWA locations, and only 50 miles from known locations in northern New Mexico as well as Pueblo Mountain Park.
I wanted to share this not so much to provide a chasing opportunity, but rather to raise awareness of what seems like a broader pattern of occurrence for this species in south central Colorado. Put it on your radar as a possible find in appropriate habitats of San Luis Valley!
Good birding, Eric
------- Eric DeFonso near Lyons, Boulder County, CO