Tweets,

Here's a thought on the nighttime singing of White-crowned Sparrow and other
birds: After dark it's safer to fly around in unfamiliar territory (given
that you're less likely to get nailed by a falcon or accipiter). It's
spring, so I can just imagine female birds, after a day of foraging, getting
out-and-about checking out some of the males on territories farther afield.
As a male it would behoove you to make your presence known.

In urban environments city lights tend to be reflected off low clouds. We
have learnt that the peregrines nesting in downtown Seattle for instance
(Stewart and Bell for those of you familiar with these birds) hunt in the
middle of the night (not only birds with nice contrasting colors like
breeding plumage goldfinches, but later in the year juvenile starlings as
well). I suspect this happens more on overcast nights then cloudless nights.
The city lights light up almost all of Elliott Bay and any songbird
traveling the 2 1/4 miles from Alki to Magnolia is like a "sitting duck" out
there over open water. What I' am watching/listening for is whether more
songbirds sing on overcast nights when it's safer to move about (lighter)
than on cloudless nights. The problem obviously is finding a cloudless night
in Seattle in the spring......

Any observations that bear this out/refute this?

Martin Muller, Seattle
MartinMuller at email.msn.com