Austin Young (first found the bird on July 29, 2017)
Jordan Ragsdale saw the bird on July 30, 2017
LOCALITY OF OBSERVATION
Fort Boise Wildlife Management Area – The main road past the Headquarters office and past the bridge over the creek. The bird was seen adjacent the plowed ag field that has been seeded with wild sunflower.
HABITAT WHERE THE BIRD WAS OBSERVED
Cottonwood riparian area with lots of shrubs and weedy plants. The riparian area is next to ponds and a plowed ag field that is planted with wild sunflowers.
SIGHTING DURATION, CONDITIONS, and EQUIPMENT USED
A warming summer day, 64 degrees and sunny. No wind. I watched the bird for approximately 30 minutes. Equipment – binoculars, Vortex 10x42
DID YOU TAKE NOTES?
No, not at all
DID YOU CONSULT A FIELD GUIDE OR OTHER REFERENCE WORK?
Yes, during the observation
WHICH GUIDE(S) OR REFERENCE(S): DID YOU CONSULT?
Sibley IPhone app
DESCRIPTION OF THE BIRD(s)
Large songbird with a blue body. It had a large head and heavy, black bill. Wings and tail were dark colored. Wings had rust colored wing bars.
BEHAVIOR OF THE BIRD(s)
I first heard the grosbeak singing. After a minute or so, it flew to the top of a large cottonwood where another bird was perched. The grosbeak chased the bird off and then it moved behind a branch. After several minutes it flew to the top of a tree near me; it sang nonstop for several minutes.
HOW AND WHEN DID YOU POSITIVELY IDENTIFY THE BIRD, AND WHAT CLINCHED THE IDENTIFICATION FOR YOU?
I had been at Fort Boise for almost 2 hours hoping to see the grosbeak. I wasn’t having any luck so I drove towards the river to turn my vehicle around so I could leave. As I drove back to the sunflower field I heard a grosbeak singing. I stopped my vehicle and got out to look for the bird. The bird was perched in a tree singing but I had to look towards the sun so I didn’t get a good look; the bird looked almost black though I could see the large bill. The grosbeak flew off to another tree and out of sight. I wanted to make sure that I was hearing a BLGR song so I played the Blue Grosbeak song that is on my Sibley app. The grosbeak immediately flew in to the top of a tree next to me and started singing. A heavy bill told me it was a grosbeak and the blue body with dark wings with rust colored wing bars definitely made it a Blue Grosbeak.
HOW DID YOU ELIMINATE SIMILAR SPECIES? WHAT WERE THEY?
Similar species include Indigo Bunting. There were 2 male Indigo Buntings in the same area, one I could see and the other one was singing but out of sight. Indigo Buntings are smaller overall than Blue Grosbeaks. They do not have the rust colored wing bars and their bills are much smaller.
On line research says that the Brown-headed Cowbird is also similar to the Blue Grosbeak. While the grosbeak looked almost black when I first saw it (because I was looking towards the sun) the heavy bill would rule out cowbirds. Once the grosbeak flew to a different tree so I could really see it I knew exactly what it was.
Because of the initial poor lighting I did wonder if I was looking at a Black-headed Grosbeak. I knew they were in the area as I had seen a male BHGR about two hours earlier. But once I saw the bird in a different tree I knew it was not a BHGR.
WHAT IS YOUR EXPERIENCE WITH THIS (AND SIMILAR) SPECIES?
I have seen Blue Grosbeaks about half a dozen times, both in Idaho and California.
I have seen Indigo Buntings 3 times, all in Idaho.
DESCRIBE YOUR GENERAL BIRDING EXPERIENCE
I started birding in the late 1990s. I am confident in identifying Idaho birds