No new sightings.

During the winters of 2008/2009 and 2009/2010, I did weekly goose surveys at
Ridgefield NWR, one season on Bachelor Island, the other season on the Roth
and Ridgeport Dairy Units, both of which adjoin the River S Unit. Both
years, all the goose survey crews shared their unusual sightings, usually in
real-time via walkie-talkies, via cell phones (for really unusual stuff when
we were out of walkie-talkie range), or in person right after the official
surveys ended. We essentially surveyed every week that migrant
white-cheeked geese were present (everything but the breeding Western
Canadas), which was 20+ times per season. As a group, we probably looked at
15,000+ white-cheeked geese during peak periods, such as November and late
February/early March. Each season, we saw a handful of odd looking
white-cheeked geese (most goose surveyors become skilled at picking out
geese that stand out, if for no other reason than to keep it interesting),
and these odd looking geese tended to get noticed throughout the season.
Never did any of these odd-looking white-cheeked goose look like the
apparent hybrid Barnacle x minima Cackling that was present on Tuesday at
Ridgefield. The fact that two were present on Tuesday, and apparently
arrived on the same day that a Barnacle Goose arrived, seems to me to be
more than coincidence.

One of the goose surveyors is attentive about tracking collars on his own
(in addition to the paperwork we turned in), especially for Duskies, whether
or not they are on his unit. Just yesterday, he showed me which of "his"
geese I reported from my unit last year, and on what dates. He also had
data from my collars from two years ago with him. Each season, we ran into
the same collars throughout the season, as expected. Most of the times, the
same collars were in the same flocks, regardless of the location where they
were seen. Sometimes they were not, though. I concluded that these groups,
whether or not "family groups", wandered and "mixed it up" on occasion, but
mostly not. I would often see a Bald Eagle scatter a flock of 3,000-5,000
cacklers, with big chunks going in different directions. Sometimes,
portions of these flocks would re-integrate, though sometimes hours later;
sometimes they appeared to stay separated for the day (I often birded for
fun until dusk after the survey). From week to week, it was almost
predictable what collars one would find with other collars, which told me
that geese develop bonds.

In addition to my goose survey duties from November 2008 until April 2010, I
regularly (usually at least once weekly) birded the River S unit during
waterfowl season from October 2006 until 2008. I have seen all sorts of odd
geese (and waterfowl in general) at Ridgefield. I have never seen a goose
that looked like the apparent Barnacle x minima that I saw today, let alone
two in the same flock with a pure Barnacle Goose.

I realize that 40 or so surveys over two goose seasons plus some randomly
timed visits in the years prior to that is far short of a scientific study,
and that no one may ever know the provenance of the Barnacle Goose at
Ridgefield. I also realize that state records committees need to err on the
side of caution, and that they can revisit historical records if patterns
develop. However, for people keeping their own individual lists,
probability seems to be pretty decent that the Barnacle Goose at Ridgefield
is a wild bird, and that it mated last year with a minima, and that family
unit arrived at Ridgefield on Tuesday. Not certainty, just probability.

On a somewhat related note:
http://www.maavianrecords.com/home/about-species-accounts/barnacle-goose-branta-leucopsis

For those who don't use probability when birding, are you certain that was a
Rock Sandpiper you saw on the coast? Which subspecies? Were those all
Purple Sandpipers I saw on Lake Michigan when I lived in Chicago? They
probably were all Rocks in the Pacific NW, and all Purples in Chicago, but
I'm not certain. As for the Purple Sandpiper I saw in Texas, I'm just not
so sure anymore, but I'll still call it a Purple.

--
Scott Carpenter
Portland, Oregon
--------------------------
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