>>> Michael Price <mprice at mindlink.bc.ca> 04/11/98
12:24pm >>>
Hi Tweets,

Rob Conway writes:

(snip)
>I think it was Richard Rowlett who
>suggested that this was likely due to the large areas of
alder forest
>which produce cones/seeds that these birds are attracted
to. Preditors,
>competitors, vegetation, food sources, micro-climates and
other
>ecosystem factors probably all contribute to this "weird"
distribution.

Interesting that in Jericho Park in the western side of
Vancouver BC there
are still pretty much the same trees, alders and hawthorns,
which used to
host anything up to ten or twelve Purple Finches Carpodacus
purpureus every
winter. It's been several years since I've seen any there at
any time.
Likewise in Stanley Park there are trees near the tennis
courts and pitch 'n
putt course which used to support a few wintering Purps.
None there now
except the odd northbound migrant, and I can say that on the
basis of
regular monitoring of that area. So, I'm wondering if the
process or
processes that over the last decade have changed the Purple
Finch from a
fairly common resident and common wintering bird to an
uncommon migrant is
or are at play regionally, and what it or they might be.

Purple Finches still are fairly common (at least as summer
residents, I'm a bit more uncertain about winter) in
undeveloped lowland deciduous or mixed forests in western
Washington. The declines, in my opinion, are connected
with urbanization, and seem most notable in the winter.
We've seen a significant decline in their numbers on the
Tacoma CBC over the last 20 years - I can't even definitely
count on finding them in my area there anymore.

Chris Chappell
Olympia, WA

Michael Price A brave world, Sir,
Vancouver BC Canada full of religion, knavery and
change;
mprice at mindlink.net we shall shortly see better
days.
Aphra Behn (1640-1689)