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.

 

Species account

 

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/