I bird a lot in Colorado and post sightings when I'm there. I enjoy reading your postings when I'm home here in Maryland, and I appreciate the interesting discussions of knotty bird identification issues. So I would appreciate any feedback from the many expert observers that read and post here on my tentative identification of a possible Brewer's Blackbird in my backyard here in Maryland yesterday, which would be a very unusual bird here.
My tale starts early Friday morning when I saw a blackbird in the tree above my feeders. We have had Common Grackles around for a couple of weeks, so I initially thought it was another Grackle until I realized it looked smaller, had dark eyes, and lacked any iridescence. I followed it as it moved around in my trees and a neighbor's trees for about 5 minutes. It never came down to the ground and spent some time moving around on the large tree limbs, unlike the Grackles which generally perch in one place until moving on.
The bird was to my west the entire time I observed it, so the early morning sun was behind me, and the bird was well lit. From all angles, its eyes were dark though the bird was not close enough to see the specific iris color. The bird was a flat, dark brownish black all over with no contrasting colors or features in its feathers. I quickly ruled out male Brown-headed Cowbird based on size, shape, and the lack of contrasting brown head. I ruled out male Red-winged Blackbird because there was no sign of the red and yellow "epaulets" on the coverts as the bird moved around, including when it did the classic blackbird display where it raised its shoulders and ruffled its feathers while doing a call. (Unfortunately I didn't think fast enough to open a window so I could hear its call.)
A Common Grackle landed near it for about a minute allowing a side-by-side comparison in the same light. The light-colored eyes of the Grackle contrasted with the dark eyes of my bird. The iridescence of the Grackle contrasted with the flat, dark brownish black look of my bird. The size difference was obvious with my bird being about ¾ the size of the Grackle but generally appearing like a smaller version of a Grackle in its overall proportions. The head looked more rounded than the Grackle, the bill was smaller, and the way the bill extended forward from the forehead of the bird was different than in the Grackle where the top of the bill flows from the line of the forehead.
The bird was too far away and left too quickly for me to get a picture. I made some quick notes and then turned to the bird guides. The highly unlikely male Bronzed Cowbird has a distinctly different shape, so I ruled it out. That left Rusty Blackbird and Brewer's Blackbird, both of which are about ¾ the size of a Common Grackle and have an overall shape like a Grackle. Given the unlikelihood of a Brewer's Blackbird here in the mid-Atlantic area, I consulted many field guides and online resources about Rusty Blackbirds which are present here in Maryland in the winter. By this point in the winter, a male Rusty could look all dark without any contrasting lighter brown or rusty markings due to feather wear (I ruled out female Rusty due to the overall dark color of the bird). My next step was to determine whether a male Rusty Blackbird in midwinter could have dark eyes. All but one of the many sources I found indicate that even a first winter male Rusty would not have dark eyes by midwinter since juvenile birds gain the light-colored eyes in both sexes by late summer/early fall. (One source, a Minnesota birding site, points out that some first-year Rusty Blackbirds can retain their dark eyes into their first spring.) So my first question for the experts is whether anyone has experience with dark-eyed Rusty Blackbirds in midwinter.
Tentatively ruling out Rusty Blackbird, I then did extensive research on Brewer's Blackbird. I am very familiar with Brewer's from many visits to Colorado in the spring, summer, and fall months, but I don't have experience with them in the winter. An adult male Brewer's should have light eyes, and I would expect visible iridescence in its feathers, both of which my bird lacked. Adult female Brewer's usually have dark eyes like my bird, but they are generally depicted and described as being more gray than my bird. However, a picture of a female Brewer's in the Bird of North American Online species account shows a fairly uniformly dark bird. Most guides and online resources talk about juvenile Brewer's starting with dark eyes and then the males turning light in late summer/early fall, like Rusty Blackbird. But the Crossley Guide to Eastern Birds shows a first winter male Brewer's with dark-appearing eyes and states "1st w [male] variable but usually intermediate between adult [female] and adult [male]. Often shows contrasting dark around eye." The Minnesota birding website mentioned above notes that some first-year Brewer's retain dark eye color into their first Spring. The other subtle difference between Rusty and Brewer's noted in several guides is the slightly decurved (bending downward) bill in the Rusty. I did not note how my bird's bill was shaped at the end so I can't use this feature. Given the dark but not iridescent coloring of the bird, it if was a Brewer's, I am leaning toward first-year male rather than a female.
I appreciate any and all feedback on my tentative identification of Brewer's Blackbird, particularly any experience with birds with dark eyes in midwinter.
Thanks.
Jim Nelson
Bethesda, Maryland
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