In the 1960's, it used to be "common knowledge" that all Snowy Owls that
came to Washington in winter died here. As a result, there were seldom
prosecutions for birds being shot back then. Of course, this belief was
incorrect but I have found few raptor species that have more misinformation
surrounding them than Snowy Owls.

When I lived in the Kent Valley of western Washington in the 1960's (it was
primarily farmland at that time), we noticed that whenever we had a large
Snowy year we usually had Snowys returning to the same locations in
subsequent years, albeit in smaller numbers. Since we did not mark them, we
couldn't be certain if they were the same birds but I think it was very
likely they were. In one instance, we had birds return for four years in a
row in ever decreasing numbers to the exact same field. So we assumed that
Snowy Owls in all likelihood did not all die down here as was incorrectly
assumed back then.

For some reason, this seems to happen a lot with Snowy Owls in the fields
by Thomle Road south of Stanwood too.

In another Snowy Owl year, several FRG volunteers helped us capture and
wing-tag 12 individual Snowy Owls on the Samish Flats in Skagit County. We
placed a single, numbered yellow patagial marker on each of these birds to
see both where they went and whether they returned to the same area. During
the first year, most of these owls remained on the Samish Flats. It seems
to be pretty ideal habitat for them. One bird even learned to roost inside
a barn like Barn Owls. During the next winter, only one Snowy returned
there. In the next winter, we observed yet another one not too far from the
original banding site. So we had definite observations of known owls,
confirming that at least some of them do return to the same area in
subsequent years. While we had all assumed this to be true, it was nice to
have definite proof.

When a non-resident raptor returns to the same wintering area, it is called
winter philopatry. Merlins, peregrines and Gyrfalcons often exhibit this
type of behavior. For example, Island Girl, our satellite tagged peregrine
just completed her fourth complete migration from Baffin Island to Chile
yesterday. She returns to the exact same perches in Chile every year.

Some Snowy Owls exhibit the same behavior, returning to the same US
wintering areas in subsequent years. But others are what is called nomadic,
i.e. they wander widely during winter and do not necessarily return to the
same area each winter. One Snowy tagged at Logan Airport in Boston many
years ago went all over the east coast, eventually returning to Logan. So
you can seldom predict what they will do as it depends on the behavior of
the individual bird. Just like us. BTW wintering Great Gray Owls are also
nomadic.

If this is a typical "echo" year, there should be fewer Snowy Owls
appearing here this year. Some birds die, others may not migrate, others go
elsewhere.

However, we have also experienced years where a low number Snowy Year is
immediately followed but an even larger irruption with considerably more
birds showing up. It may be too early to tell just yet but it seems like
this may be happening this year with so many observations in unusual places.

It would be interesting to compare numbers of sightings between the two
years. Also, accurately ageing any sick or injured birds in hand would let
us know if they are birds produced last summer in the Arctic.

Here is some recent information on ageing and sexing these owls from
www.frontierscientists.com, an Alaskan website. Note the article by Mat
Seidensticker.

"Birders usually want to know: Is it Male or Female? The Burns (Oregon)
Snowy has been called both. Denver Holt, an owl researcher
http://www.owlinstitute.org/ who has spent the last 20 years studying the
Snowy Owl up in Barrow, is cautious about identifying the sex. ?The more
experience you get the more questions you have,? Holt says. Yet the Journal
of Raptor Research Dec 2011, Vol. 45, No. 4: 290-303 has just published an
article ?Sexing Young Snowy Owls? by lead author Mathew T.
Seidensticker<http://www.bioone.org/action/doSearch?action=runSearch&type=advanced&result=true&prevSearch=%2Bauthorsfield%3A(Seidensticker%2C+Mathew+T.)>,
co-authored by Jennifer
Detienne<http://www.bioone.org/action/doSearch?action=runSearch&type=advanced&result=true&prevSearch=%2Bauthorsfield%3A(Detienne%2C+Jennifer)>,
Sandra Talbot<http://www.bioone.org/action/doSearch?action=runSearch&type=advanced&result=true&prevSearch=%2Bauthorsfield%3A(Talbot%2C+Sandra)>,
and Kathy Gray<http://www.bioone.org/action/doSearch?action=runSearch&type=advanced&result=true&prevSearch=%2Bauthorsfield%3A(Gray%2C+Kathy)>,
and Holt available at this link
http://www.raptorresearchfoundation.org/publications/journal-of-raptor-research/current-issue
.

<http://frontierscientists.com/wp-content/uploads/2011/12/SowlPost.jpg>Seidensticker
and fellow researchers based their paper on a study of 140 owls from 34
nests (at Barrow). Specifically they looked at a secondary flight feather
#4 on the left wing. Then they compared their predictions with blood tests.
The model that correlated their data said they were 98% correct, actually
they were 100% right. In short what the secondary feather #4 told them was:
the female owl had a marking that they called a bar because it touched the
feather shaft, while the male had a marking they called a spot or blotch
that did not touch the feather shaft."

So I think that it is really important to understand how challenging it can
be to age and sex these birds in the field. If Denver Holt is cautious, I
would be too.

Bud Anderson
Falcon Research Group
Box 248
Bow, WA 98232
(360) 757-1911
falconresearch at gmail.com
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