Hawaiian Ducks recorded per party hr on the Kapa'a Christmas Count, Kaua'i, 1971-

2014 (see Count Page), showing a significantly increasing recent 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/