Red-whiskered Bulbuls recorded per party hr on the Waipi'o Christmas Count,

O'ahu, 1977-2007 (see Count Page), showing fluctuation but no significant trend.

 

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/2009/