- Grey-blue duck with pink bill.
- Males give characteristic, hoarse whistle “whio”, while females give a rattling “crack” call.
- Juveniles have a grey bill and lack chest plumage colouration.
- Formerly widespread on fast-flowing, hill-country streams mostly within indigenous forest.
- Range now much reduced, centred on Volcanic Plateau and Te Urewera in North Island and western side of Southern Alps.
- Possess a fleshy lobe to undersurface of bill believed to assist with gleaning invertebrates from rocks and aquatic debris.
- Pairs are territorial all year.
- Nest under cover on stream banks.
Association with Plantations
- Can be found in high quality and remote streams within plantation forest estates.
- Most associations with plantations are in the Central North Island and West Coast areas.
- Predation of eggs, young and adults by stoats and other predators.
- Loss of native forest and shrubland habitat along streams through development.
- Habitat flooding locally through hydro-electricity development.
- Shooting, particularly in the past.
- Trout may compete for food in some areas.
Management Options and Methods
- Protection of wide riparian zones of indigenous species along streams likely to be used by whio.
- Consider implementing predator control if pairs of whio are present and/or other groups (e.g. community/DOC) are implementing predator control in adjoining areas. Target predators are primarily mustelids and cats (refer kiwi).
- Comply with best forest operational management practices to avoid damage to riparian areas and saltation of streams.
- Raise awareness of staff and contractors of the presence of whio and the need to protect them.
- Survey for presence of whio looking for birds, their sign (white faeces on rocks in streams) and listening for calls.
- Contact local DOC staff for contributing to any existing monitoring programmes locally.
- Maintain records of sightings, including broods.
- Report findings to DOC.
Further Information and Support
- Blue duck recovery plan. Threatened Species Recovery Plan 22. Department of Conservation.
- Heather and Robertson 2000. The Field Guide to the Birds of New Zealand.
- Predator control and monitoring – Department of Conservation.
- Whio: Saving New Zealand’s Blue Duck by David Young (2006, Craig Potton Publishing NZ).
- Department of Conservation website.