I was just reviewing Vashon Island Christmas Bird Count numbers as the count now has ten years of data. One of the interesting species is Black Scoter, it's regularly way up one year and then way down the next throughout the decade. It's apparent in the charts you can make on-line at http://audubon2.org/cbchist/graph.html but even more visible in the numbers for the sections of Vashon's CBC circle that are just Vashon and Maury Island.

Does anyone know why the Black Scoter would show a regular up/down cycle? I haven't run the numbers for other counts, maybe it's just a Vashon thing.

Ed Swan
Vashon Island
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