Good morning Tweeters,
The arrival yesterday of Green Lake's first swallow of the season
(to my eyes, at least) prompted me to begin making the shift from lurker
to contributor; spring seems a good time for new things. I notice that our
little urban lake doesn't make it onto Tweeters very much (I think the
last time was when someone cautioned people about using binoculars out
here for fear of being taken for a peeping Tom/Thomasina...). However,
Green Lake offers not only a plethora of migratory and stationary birds,
but also the opportunity to see them at fairly close range over long
periods of easy access: a terrific setting for down-to-earth natural history.
Come visit.
For instance, I recall a Tweeters posting a few days ago asking
about where to see Scaup up close. Yesterday and this morning, near the
Evans Pool area of the lake, I watched one Greater and 2 Lesser Scaup
males swimming about 2 feet below my two feet at the edge of the lake.
With binoculars in hand, I was within about a virtual inch of them. This
morning I was (finally!) able to distinguish a female Greater from a
female Lesser Scaup (I think) using the same technique.
Between my two circuit walks yesterday and this morning, I counted
31 species (including one Eurasian Wigeon and two Killdeer; not counting
gulls or the Bonaparte's Gull 3/12 or the 2 Red-Breasted Sapsuckers of a
couple of weeks ago). This is a wonderful time of year here, of course,
because most of the winter birds are still here (though there's only one
Common Merganser left) but the spring birds are also beginning to come in.
Dozens of male buffleheads are flirting outrageously with the females,
bucking their heads, chasing each other around, and coming in for dramatic
splash landings in front of other males. Coots are cozily preening each
other. A black-capped chickadee is beginning work on his/her nest hole on
the west side of the lake.
So as not to make my first posting too long (though it probably already
is!), I'll just close here with a question from last year's pied-billed
grebe nesting season. There were about 14 nests along the west side of the
lake, most within about 15 feet from shore. The northernmost nest was
constructed--and reconstructed and reconstructed--by two grebes who never
seemed to get it right. They must have laid 8 separate clutches of 1-2
eggs, none of which lasted longer than about 2 days. In two winters of
grebewatching (perhaps 30 nests or more), they're the only pair I've seen
fail.
How do grebes learn how to build nests, anyway? I assume part of
their knowledge (or guesses) comes from watching their parents do their
constant repairing and replenishing of the nest after the young are born.
But they would never have the chance to witness the building of a new nest
from scratch. The two grebes in question seemed not to understand that
they had to choose fairly buoyant material to keep the soggy nest from
sinking right away--or at least that's how I interpreted the problem. Any
ideas? Is there genetic programming involved? Why would these guys get it
wrong when everyone else gets it right?

Trileigh Stroh

Department of General Science
Seattle University