mountain duck
/ˈmaʊnt(ɪ)n ˌdʌk/noun
1 Australian. The Australian shelduck, Tadorna tadornoides, which has a chestnut breast and a white ring around the neck.
2Originally NZ. A blue-grey New Zealand duck, Hymenolaimus malacorhynchos, found chiefly on streams and rivers in mountainous areas.
Origin
Early 18th century; earliest use found in Atlas Geographus. From mountain + duck.