At least in my observations, and I expect others have observed the same,
Siskins feed mostly on Red Alder (Alnus rubra) seed in the winter, our most
abundant tree in much of the area west of the cascades in OR, WA and BC, so
I doubt that winter food supply is much of a factor in their decline. I
would agree with those that point to disease (I highly doubt that West Nile
would be getting many of them). I would hope that many of those left are
relatively resistant to the disease(s) that have been killing them and/or
that the disease will have run its course and the Siskins will indeed bounce
back, but, of course, that remains to be seen. As others have noted, Siskin
populations have always been relatively cyclical.

Stewart Wechsler
Ecological Consulting
West Seattle
206 932-7225
ecostewart at quidnunc.net

-Advice on the most site-appropriate native plants
and how to enhance habitat for the maximum diversity
of plants and animals
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-----Original Message-----
From: Wayne C. Weber .,..
The numbers of siskins should be closely watched in the near future.
However, there is no question that disease outbreaks, as well as
food availability, can have a big effect on their numbers over
large areas.

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