Japanese Bush-Warblers recorded per party hr on the Waipi'o Christmas Count, O'ahu, 1977-2014 (see Count
Page), showing general increases
from 1977 to 1993 followed by general decreases from 1993 through 2014. 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/