Blue duck/whio (Hymenolaimus malacorhynchos) are nationally endangered. This survey compares data to a previous one done over the summer of 1999/2000 to estimate the population in a number of the rivers in the north west catchments of Kahurangi National Park.
Occasional Publication No. 84
ISSN 0113-3853 (print), 1178-4113 (online)
ISBN 978-0-478-14798-8 (print), 978-0-478-14799-5 (online)