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“Bicolored” Blackbird found at Malibu Lagoon

May 4, 2011

Bicolored Blackbird - note lack of yellow margin on epaulets (J.Kenney 4/11)

A few years back, while watching either a Red-winged or Tricolored Blackbird (getting old, don’t remember which), I made a personal discovery. Until then, I had always assumed that the yellow or white “margin” on the red epaulets was the terminal end of the mostly red feather. This bird was in full display; it erected its epaulets to the maximum, I could see right to the base of the feathers, I saw that the “margin” was actually a separate set of feathers lying below the red epaulet feathers, and these sub-epaulet feathers were completely white (or yellow) right to where they grew from the skin.

Bicolored Blackbird - subspecies or accidental aberration of Red-winged? (J.Kenney 4/11)

These pictures were taken by local photographer James Kenney on 4/30/11 about 8 a.m, at the 2nd footbridge on the path to the beach. So far as I know at this time, it’s the first appearance of the Bicolored Blackbird at the lagoon, and it may well be its southernmost sighting. Dan Cooper commented on the pictures, “I can’t remember seeing one down here, though it’s a common form up in central California to the Bay Area, and probably occurs rarely throughout populations.” He also passed on a Wikipedia citation written by central Californian bird maven Alvaro Jaramillo: “There are a number of subspecies, some of doubtful status, which are  mostly quite similar in appearance, but the ‘Bicolored Blackbird’ A. p. gubernator of California and central Mexico is distinctive. The male lacks the yellow wing patch of the nominate race, and the female is much darker than the female nominate. The taxonomy of this form is little understood.” Commenting on Alvaro’s citation, Dan added, “I can’t imagine that a race occurs as disjunct in both coastal California and central Mexico (and not in between), so it may be, as I suspect, a normal/relatively common variation – like the yellow house finch, that simply”pops up” here and there across the huge range of the species.” I concur with Dan, but I wonder whether the margin feathers in the Bicolored are merely shortened or are completely absent. If anyone knows, drop me a line or post a reply here. I found an interesting article on the web but – lacking sufficient academic credentials – could get access to only the first page: The Status of the California Bi-colored Blackbird, Joseph Mailliard, The Condor (Cooper Ornithological Union), March 1910.  If anyone can send this article to me, I’d greatly appreciate it and will report what (if anything) I discover.

These pictures and comments have been added to our Unusual Birds at Malibu Lagoon page (aka Lagoon Birds).  [Chuck Almdale]

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2 Comments
  1. May 18, 2012 7:40 pm

    How about *hot pink*? Spotted a regular resident on San Francisco Bay Trail between Heron and Oyster Bay. It’s definitely not a typical red.

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  2. Chuck Almdale permalink
    May 5, 2011 3:04 pm

    Addendum as of May 5, 2 p.m.

    I corresponded with Kimball Garrett at the Natural History Museum of L.A. County, and gleaned this additional information, which I hope I record correctly.

    The red epaulets on the Red-wing Blackbird Agelaius phoeniceus (RWBB) (both “Red-winged” and “Bicolored” forms) and the Tricolored Blackbird Agelaius tricolor (TCBB) are the feathers known as lesser wing coverts (lessers). The “margins” – yellowish in the RWBB and white in the TCBB – are the median wing coverts (medians), which lie beneath the lessers. The “margin” which we see in the field are the outer (distal) several millimeters of the medians, protruding beyond the lessers.

    In the RWBB, the medians can be entirely black, entirely yellowish or mixed black & yellow. For the TCBB, it’s black, white, or mixed white & black.

    For the “true” “Bicolored” Blackbirds (BCBB) found around the San Francisco Bay area, the medians are entirely black. The central valley ssp. A.p. californicus, found south to Kern Co., is variable and may show some buff in the margins. Another ssp. is found in the central Mexican Highlands A.p.gubernator, but there are no ssp. found between central California and central Mexico.

    Our local Red-winged Blackbird is the A.p. neutralis subspecies. This ssp. can sometimes lack yellow in the median coverts, and thus may look like a Bicolored. It’s most likely that the pictured bird at the lagoon is a variant of this subspecies. Kimball says, “Of course if the median upper secondary coverts have been molted and are missing that can also account for the lack of a visible yellow borders, but that isn’t the case here.”

    Central Valley BCBB’s breed with typical RWBB’s, and intergrades can be found as far south as the Gorman/Tejon Pass area. Kimball doesn’t know of any published evidence of movements of Bicolored birds outside of their resident range.

    The checklist of North American birds maintained by Cornell Laboratory of Ornithology, upon which the Clements Checklist of birds is based, lists the A.p. neutralis ssp. as part of the “Bicolored Group” of Red-winged Blackbirds. Research on these birds seems to be a bit up in the air. Kimball feels that because the neutralis ssp. has a variable yellowish border, it doesn’t really belong in the Bicolored group.

    Link to Cornell Checklist: http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist

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