Ryan Stewart, of Gore, asks :-
I photographed these ducks, which are smaller than mallards but have a larger beak and are shy. What are they and what is known about them?
Zane Moss, a zoologist with Fish and Game (Southland), responded.
The two ducks that you managed to photograph are actually different species. The brightly coloured bird is a male New Zealand shoveler, (Anas rhynchotis variegate), while the grey/brown individual is a grey teal (Anas gracilis).
The New Zealand shoveler is protected as a gamebird under schedule 1 of the Wildlife Act (1953), and may only be harvested within the limits and conditions imposed by Fish & Game during the gamebird hunting season. Fish and Game monitor the numbers of shoveler through a nationally coordinated program which involves obtaining counts of the birds at favoured locations throughout the country. The data is then analysed with harvest data that is obtained throughout the hunting season, allowing Fish and Game to determine that the harvest level is sustainable.
Generally New Zealand shoveler are only harvested occasionally by hunters, with some favouring their relatively rich flavours to those of other gamebirds. Harvest of shoveler contributes less than 10% of the total harvest of waterfowl nationally.
The most distinctive feature of the shoveler is its broad bill which is noticeably longer that the bill of other ducks and spoon-shaped, hence ‘shoveler’. The bill has rows of fine hair-like projections on both the upper and lower margins, called lamellae, which mesh together when the bill is partially closed. This special adaptation allows shoveler to sieve very fine particles out of water or very soft mud, such as seeds or insects or microscopic water animals called zooplankton.
Grey Teal are a relatively recent arrival, thought to have migrated from Australia in the mid-19th century to escape widespread drought. They are the smallest of New Zealand’s ducks and their size, overall grey colouring and blood-red eye make them relatively easy to identify. At this time grey teal are not classified as a gamebird. However, there is some interest in changing that status to allow a limited harvest. Observations suggest that their numbers are quite high, with some thousands observed on water bodies such as Lake Ellesmere and Wainono lagoon. Despite grey teal not being classified as a gamebird, many hunters have erected nesting boxes on wetlands which assisted their productivity.