Sanderlings recorded per party hr on the Waipi'o
Christmas Count, O'ahu, 1977- 2007 (see Count
Page), showing a significant
decline. The variability in numbers otherwise may reflect ENSO events, with higher numbers
generally being recorded in Hawaii during El Niņo years. Graphs of Christmas Count data developed as part
of The Birds of the Hawaiian Islands: Occurrence, History, Distribution, and
Status by Robert L. Pyle and Peter Pyle http://hbs.bishopmuseum.org/birds/rlp-monograph/2009/