The present discussion concerning Pine Siskin numbers sent me to the CBC
data base at the Audubon website:
http://www.audubon.org/bird/cbc/hr/index.html



Looking at Pine Siskin data from 1980 to present, in the state of
Washington, there are huge peaks and valleys, however the overall trend
seems to be an increasing population.



I would encourage you to take a look at this site, as this is where all the
CBC data goes after compilation. A recent article in American Birds
referenced CBC data when looking at Cooper's Hawk and American Kestrel
trends, so there is some scientific merit to using the data. One does have
to be a bit cautious though, for in the instance of owls, owling data
(number of hours, miles owled, etc) is not used in subsequent calculations
relevant to owls. An eye opener for me was to look at the last 15 years of
data for Western Screech-owl and Barred Owl in Washington.



-Jamie



J. Acker

Bainbridge Island, Washington

owler at sounddsl.com