Subject: [Tweeters] interesting pattern in Vashon CBC data for scoters
Date: Dec 13 22:47:35 2012
From: Ed Swan - edswan at centurytel.net


I was reviewing the 12 years of data for the Quartermaster Harbor part of
the Vashon CBC and noticed an interesting pattern in the scoter data. For
all three species, there is a periodic up and down movement in numbers, up
on odd years and down on even. Brandt's Cormorant followed the same
pattern. I'd seen this in the Black Scoter data a few years back but not
checked the others.



Any ideas what causes that pattern?



Ed

Ed Swan



Guide

Birding Vashon Island and Beyond

206.463.7976

mailto:edswan at centurytel.net