For what it's worth, there has been a pair of Black-billed Magpies living at the
LA/Long Beach Harbor for the past year-- obviously brought there, possibly
European Magpies brought by ship!

That said, a single bird at this relatively non-urban location on the west slope
could easily be a wild bird.

Steve Hampton
Davis, CA

--- In central_valley_birds@yahoogroups.com, Sally Walters&Don Schmoldt
wrote:
>
> Then there is the sad probability of human transportation or the release of a
rehabilitated bird....
>
> Sally Walters
> Sacramento CA
> BajaOwl@...
>
>
>
>
> On Dec 14, 2010, at 8:26 PM, Bruce Webb wrote:
>
> > I recall a discussion in American Birds years ago, or perhaps as far
> > back as Audubon Field Notes, by Tim Manolis of a report of a
> > Black-billed Magpie reaching the western Sierra. I cannot recall in
> > which county it was seen, but it was south of PLA. Tim will no doubt
> > chime in when he (ever) gets back through the snow from the Susanville CBC.
> >
> > Occam's Razor and proximity to South Lake Tahoe would support the
> > rationale of a Black-billed Magpie rather than a Yellow-billed appearing
> > with selective soft part melanism. The Hwy 50 corridor seems conducive
> > to allowing one of the common South Lake Tahoe magpies to reach the west
> > slope of El Dorado county.
> >
> > Several species of corvids in the neotropics have yellow bills as
> > juveniles that darken when adults. Someone with more knowledge of the
> > literature can hopefully comment whether soft part hyper-melanism occurs
> > in wild birds.
> >
> > Bruce Webb
> > Granite Bay, CA
> >
> > On 12/14/2010 6:28 PM, ERPFROMCA@... wrote:
> > >
> > > I have just uploaded to CVBirds and CALBIRDS a photo taken late last
> > > month
> > > near Pilot Hill, western El Dorado County (elev 800 ft) of what
> > > appears to
> > > be a Black-billed Magpie with Yellow-billed Magpies. (photo by Terry
> > > Armstrong (_http://imagesbysydney.com_ (http://imagesbysydney.com) )).
> > >
> > > Chris Conard first brought this photo to our attention. The photo is
> > > on the
> > > CVBirds Yahoogroups page in the 'Crows, etc' folder and in the CALBIRDS
> > > page in the 'Mystery Birds' folder.
> > >
> > > This would be, as far we can determine, the first documented (by specimen
> > > or photo) Black-billed Magpie ever found on the west side of the Sierra
> > > Range. The mystery is that, from this photo, the bird appears to be
> > > the same
> > > size as the Yellow-billed Magpies nearby. Of course, determining size
> > > from
> > > photos can be VERY tricky if the birds are not right next to each
> > > other. The
> > > bird with the black bill is behind the Yellow-billed Magpie, but how far
> > > behind Jeff Davis has suggested that this may be a Yellow-billed
> > > Magpie with
> > > a pigment abnormality (e.g. hypermelanism of the soft parts). On the
> > > other
> > > hand, in Sibley's Guide to Birds he suggests that southern Black-billed
> > > Magpies are smaller than their northern counterparts, though he cites no
> > > source to support this.
> > >
> > > So I put two questions to the group.
> > >
> > > 1. Has anyone ever seen or have reliable info about Yellow-billed Magpies
> > > exhibiting a pigment abnormality like this Since many thousands of
> > > magpies
> > > were collected during the West Nile Virus outbreak of a few summers ago,
> > > perhaps such a specimen was seen
> > >
> > > 2. Does anyone know of evidence for Black-billed Magpies being smaller in
> > > the south, and if so, how small can they be Can they approach the
> > > size of a
> > > Yellow-billed Magpie
> > >
> > > It might be best to send me your replies off line and I can summarize for
> > > the group later.
> > >
> > >
> > > Ed Pandolfino
> > > Carmichael, CA
> > >
> > >