There is a good article on the various crossbill calls on E-bird
www.ebird.org . Its the second story on the home page.
Pine Siskins and Red-breasted Nuthatches are following the winter
patterns that were predicted for them in late summer based on the available
food supplies in Canada. Siskin food supplies were scarce while nuthatch
supplies were good, therefore there should be a major movement of siskins,
but not of nuthatches which seems to the case in Maryland.
To see the present distribution of these species in North America go
to www.ebird.org , click on View and Explore data, then Map. Key in the
species and set the time period you want and a distribution map will appear.
Paul Woodward
Fairfax City, VA
|