Rob Saecker wrote:

>(though how one does accurate estimations of dunlin escapes me; they're
little, and they move around all the time. <

Estimating shorebird numbers - when there are lots of them - does
require special techniques and lots of practice. At the Copper River
Delta, the researchers make daily surveys during migration, some
on foot, some from the air. They practice by using videos, where
you can check your accuracy by freezing the frame and actually
counting individuals after making an estimate; and by dropping
handfulls of rice on the floor, making an estimate, then picking up
and counting the kernels.

Makes me think of the old jokes about counting all the legs and
dividing by 4 (or 2 in the case of birds) :)

Chris Maack
Anchorage, AK
CMaack at compuserve.com