Burt Guttman wrote: "The point of my previous message was that since I
observed displaying in the depths of the winter months, it didn't appear to
be a sign of spring, a behavior brought on by more daylight and more
hormones flowing. If I understand you correctly, Dennis, displaying,
pairing, and copulating in these ducks isn't associated with springtime, and
it's only in the spring when the gonads have enlarged that copulation
results in fertilization."

Burt, that's correct. The male's testes begin to enlarge on the wintering
grounds, but the reason fertilization happens only on the breeding grounds
(after the female has built a nest) is because that's when the female's
ovary begins to produce fertilizable eggs.

Dennis
--
Netta Smith and Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115