[Birdtalk] RE: Possible Tricolored Blackbird in Holladay

[Tim Avery]

Pomera, et, all,

I am going to look like the young curmudgeon, if there can be such a thing,
and go out on a limb (not too far) and venture that thee bird you saw is a
Red-winged Blackbird.

There are hundreds of species of birds in North American that are known to
wander during migration, the winter, the spring, post-breeding, the fall,
etc.  Some species wander very short distances, and others can cover
hundreds if not thousands of miles out of their typical range.  These birds
could be expected, or even fantasized to show up at any number of odd
locations, based off patterns of vagrancy and sheer dumb luck.  Take for
instance a Magnificent Frigatebird in Juab County... Or a Whip-poor-will in
Cache County (believe that one boggles my mind every time I think about
it).  Those could be called dumb luck.  Or perhaps we could go with jaegers,
or warblers, or tanagers, or sparrows.  These species have wide ranging
migration patterns, and tend to be seen away from their typical ranges are a
much higher frequency that the previous 2 species mentioned.  These would be
birds that some expect every year, like Blackpoll Warbler, or Parasitic
Jaeger in Utah.  Although for many species if not most, there isn't an exact
science to predicting a species showing up, there can be some degree of
guesswork along with historical data that can be used to work at finding
such species.  We know that jaegers migrate south between July and November,
and Utah has a number of September and October sightings.  So the best time
to look for a jaeger in Utah would be in September or October.  Or we know
that the month of September is usually the best month for vagrant southbound
migrant warblers in Utah, so spending some time at migrant traps in the fall
is a good way to increase your odds of finding a rare warbler.

Then there are species that just do not wander.  Take for instance Gunnison
Sage-Grouse, White-tailed Ptarmigan, or Himalayan Snowcock.  Okay those
really aren't fair examples, as they are all game birds and well, their
ranges are very limited, and habitat specific.  But none-the-less, you arent
going to find a ptarmigan at Brighton, or Sundance... You get my drift.  So
lets use some more realistic songbird examples, like LeConte's Thrasher,
Olive Warbler, Seaside Sparrow, and Tricolored Blackbird.  Most of us in
Utah probably haven't seen any of these species--definitely not in Utah
anyways.  If you have gone to the east coast, or Florida, Louisiana or Texas
along the gulf, you have probably seen Seaside Sparrow. If you had spent
time in the mountains of southeast Arizona you probably have Olive Warbler
on your life list.  And if you've been lucky to come across a LeConte's
Thrasher in the deserts of Arizona, Nevada or California--you may have seen
a LeConte's Thrasher  (or you are one of the lucky few who has come across
this species in Utah.  I think Merrill Webb is in this exclusive club--I
still have high hopes for myself!).  And if you have spent time in any
marshes throughout California you have probably seen a Tricolored
Blackbird.  You may have even come across one in southern Oregon, or extreme
western Nevada.  These species have very specific habitat, climate, food,
biological characteristics that limit their range to very specific areas.

Tricolored may wander too the north a bit, and too the south a  bit, and
even just a tidge east.  But there are ZERO records from outside the Pacific
Time Zone for the very reason, that this species just does not wander.  Here
is a link to the eBird map for Tricolored Blackbird (its flash):

*http://tinyurl.com/cr7f6n*

If you couldn't view that click on the following for a static map:

*http://www.mbr-pwrc.usgs.gov/id/framlst/CBCMap/ra5000.gif*

The one location I would imagine this species could potentially show up in
Utah would be in Washington County (mind you I also imagine that
Pyrrhuloxia, Greater Pewee, and Hepatic Tanager along with a  number of
other species "could" show up down there).  But even that would be a long
shot.  Besides the vagrancy issue, plumage can be a tricky boat.  I can't
count the number of Red-winged Blackbirds I have seen that have had white
median coverts.  Depending on how worn the feathers are or even based off of
some defect, white median coverts are not out of range for a Red-winged
Blackbird.  Here are some pictures, I only have one that had whitish coverts
but...

*http://www.timaverybirding.com/photos/thumbnails.php?album=87*

With that said, I applaud Pomera for her report.  And since I didn't see the
bird, I cant comment on its appearance, or song, etc  of the individual, I
just wanted to provide a little input on the scientific side of things.
With any vagrant species, careful observation and field notes, along with
photographic, video or recorded evidence is always helpful in ID'ing these
birds.  Pomera has her fair share of rarities under her belt ;)

And who knows, maybe I am dead wrong on this... It wouldn't be the first
time--nor will it be the last!

Good Birding and KEEP THOSE REPORTS COMING!

Tim
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