More than 100 rare whio ducklings have been spotted by Department of Conservation rangers and volunteers during a recent survey.
The 107 ducklings were spotted during a visit to Whirinaki Te Pua-a-Tane Conservation Park near Minginui in the central North Island, DoC ranger Jacob De Vries said.
"Considering there are only an estimated 3000 whio left in the world, over 100 whio chicks in one security site is an outstanding result."
The work to survey the ducklings was done by six volunteers, detection dog Beau, and his handler DoC ranger Andrew Glaser who waded through ice-cold rivers during the work.
Volunteer John Black was so committed to counting ducklings he even spent New Year's Eve at Central Whirinaki Hut.
"Whio are masters of disguise who look just like stones in the river until they move. Seeing new chicks is really rewarding – they are little fluff balls that never stray too far away from their parents," he said.
There is an increasing number of adult breeding pairs in Whirinaki Forest.
With help from Genesis, DoC is working to double the number of whio breeding sites, boost pest control efforts and enhance productivity and survival for the rare native ducks.
There are currently 38 adult breeding pairs and hundreds of kilometres of trap lines in Whirinaki to protect vulnerable nesting mothers and ducklings from the threat posed by introduced pest species such as rats and stoats.
Nest cameras show that without pest control nearly 95 per cent of female whio are killed while sitting on their nests.
In addition to trapping, the Whirinaki also benefits from regular pest control operations. Because the Whirinaki Forest is an ideal environment for whio, when pests are managed the population grows rapidly.
As the ducklings grow up, they may travel to adjacent forests and repopulate areas that no longer have whio.
More information on the Whirinaki Te Pua-a-Tane Conservation Park is available online at www.doc.govt.nz/whirinaki
- A threatened species of native duck that is only found in New Zealand's fast flowing waters.
- Featured on New Zealand's $10 note and with an estimated nationwide population of fewer than 3000 birds, whio are rarer than kiwi.
- The only exist where there is quality fresh water and an abundance of life.
- Predators include stoats, ferrets and cats which have an impact during nesting time when eggs, young and females are vulnerable, and also when females are in moult and can't fly.
- Extensive trapping and the Whio Forever Project has seen an increase in numbers.
- Whio cannot be moved to predator-free islands like other species because of their reliance on fast-flowing rivers.
- Pairs occupy approximately 1km of water each – so they need a lot of river to sustain a large population. They fiercely defend their territories, which makes it difficult to put them with other ducks in captivity.
- They are susceptible to flood events which, destroy nests, fragment broods and wash away their valued food source.
- Whirinaki Te Pua-a-Tāne Conservation Park is one of eight "Whio Security Sites" in New Zealand, it's home to 51 endangered species.