On 21 Jun 2003, Guttman, Burt wrote:

> Taking a relaxed, only casually birdy walk with friends at Nisqually
> NWR today, we found two amazing broods or families of Common
> Mergansers. Both were on the Nisqually River. First we saw, at a
> distance, one female with her brood of at least 15 quite young birds;
> later another female appeared very nearby with about 16 much older
> young, in juvenal plumage and getting almost as large as mama.

On Tuesday morning, 17 June, I was on the Nisqually River dike near
the old dike break when I saw a female Common Merganser with ~22
partly feathered (class II) young moving up river against the ebbing
tide. Needless to say I was a bit befuddled. I made a number of
counts of the often tightly packed group of young, always in the
range of 21 to 23. And never saw more than one adult female.

Bellrose (Ducks, Geese, and Swans of NA) summarizes Bent's reporting
(which Burt mentioned) and goes on to report other research from the
1970s that tells of two or more females simultaneously laying eggs in
the same nest, resulting in apparently extraordinary clutchs.


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Douglas Canning
Olympia, Washington
dcanning at nisquallyestuary.org
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