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CBC Uses



	I'd have to say yes and no to Steve's argument about making judgements
about population from short term CBC results.  I agree that you can sometimes
see long term trends.  For example, there are some species that were seen
regularly or in good numbers on the Buncombe County count in the 70's that now
rarely appear or appear in very low numbers in the 90's (ex. Bobwhite,
Meadowlark, Purple Finch).  The opposite is also true.  Some birds that did not
appear in the 70's now appear in good numbers in the 90's (ex. Canada Goose,
House Finch).
	On the other hand, sometimes you see strange fluctuations in the short
run.  A few years ago the Buncombe count showed very low numbers of Blue Jay
for no apparent reason, weather was fine and there were more than usual
participants.  If you see this occur with just one species, while all of the
other song birds, for example, show no other unusual trends, then you begin to
wonder.
	Dare I delve into that touchy issue of those darned Ruby-crowned
Kinglets.  Oh well, I'm 200 miles away from Raleigh/Durham, so I guess the
flames won't reach me, and I'm getting a little weary of the goldfinch food
issue, so here goes.  As you may recall, I did not think the argument for
massive loss of Kinglets from the storm last year was a very strong one. 
Looking at this years data, I'm still not convinced for the following reasons:
1.  If you look at the long term data, the number of RCK's in the
Raleigh/Durham area (looking at a few of the count circles from that area) on
last years CBC was lower than usual, and this, I believe (correct me if I'm
wrong) was before the big storm.  It doesn't look as though there were as many
kinglets there to start with.
2.  This year the reports from that area seem to show about 3 times as many
RCK's as last year, both in actual numbers and almost that in number/party
hour.  Of course, as I said, last year's RCK count was lower than usual.  One
would think that the cold weather this year might have reduced numbers, but on
the other hand, maybe the cold weather kept the birds more active and easily
seen this year.  It's hard to say sometimes what influence weather has and the
influence certainly must vary with different species.  The predictions made
last year that you might be seeing low numbers of RCK's for some time, though,
seem not to have come true.
	So why aren't they true?  Whether it was the storm or other factors
that caused the population to be lower last year (I have not looked to see if
other species were lower as well), the population does seem to have increased
this year.  In fact, two of the circles from that area that have reported so
far, are in the top 20 circles in the nation for most RCK's counted.  Maybe
some of the kinglets did move off to less snowy areas during the storm last
year.  It also seems that they must have done quite well on the breeding
grounds this past summer as has been suggested.
Was there less competition?  Do the birds that winter in the Raleigh/Durham
area all breed in the same area as well?  I don't know.
	All the variables make analysis always open to question.  Maybe
sometimes gut feelings are just as good, I don't know.  My profession is
analyzing stream and river water quality and all the variables there drive me
nuts.
	Anyway, I'm glad the kinglets are back because I like them and I guess
you all do, too.  And I think that the Christmas Count data can be very useful
when it is looked at as a whole.
Marilyn Westphal/Hendersonville, NC    Email: mjwestphal@unca.edu