Fernbirds inhabit wetlands throughout New Zealand. They are a potential indicator of wetland health because they are dependent on the presence of high quality and ecologically diverse habitats and rich food supplies.
Fernbirds have declined significantly since humans began draining wetlands. They are now classed globally as at risk, declining.
They have disappeared from large areas of New Zealand, including Wairarapa, Wellington and Canterbury.
- ~1500 pairs estimated on Snares Islands (8 pairs/ha)
- 2.4 pairs/ha near Whangarei; 3 birds/ha at Tiropahi, West Coast
- 1.89 birds per 5-min count on Great Barrier Island
Many local populations have been lost due to drainage of wetlands and conversion to pasture, combined with predation by introduced mammal such as cats, rats, dogs and mustelids.
On Muttonbird Islands, several populations were wiped out by introduced ship rats (Solomon, Pukeweka and Big South Cape Islands), and by weka (Kundy and Jacky Lee Islands). The fernbirds on Great King and Aldermen Islands died out probably due to vegetation succession.
The translocation of fernbirds has led to some island populations being established or reestablished, eg North Island fernbirds to Tiritiri Matangi Island, Stewart Island fernbirds to Kundy Island, and Codfish Island fernbirds to Putauhinu Island.
Wetlands support a wide range of threatened bird species in New Zealand. However, management techniques for restoring their populations are poorly developed.
DOC is focusing on developing methods for surveying fernbirds systematically. These methods will enable people to establish baseline data and distribution maps; identify important wetland habitat types for conservation and measure the response to management such as pest control; and habitat maintenance and restoration.
We have been developing ‘call counts’ for fernbirds. These take place with either an observer listening for set times at dawn or dusk using call lures, or with new automatic recorders (electronic recorders developed by the DOC Electronics Lab) recording calls remotely.
We are also actively developing methods for restoring wetlands through the Arawai Kākāriki Programme. At Awarua wetland in Southland, fernbird numbers have increased steadily since predator control commenced along the Tiwai Peninsula. A similar, but larger scale (c.3,500 ha) predator control programme has been started, aimed at increasing numbers of fernbirds and other wetland birds
You can help
Report sightings or calls of fernbird to your nearest DOC office.
Help protect our native birds
When visiting parks, beaches, rivers, and lakes
- Only take dogs to areas that allow them, and keep them under control.
- Check for pests when visiting pest-free islands.
- Leave nesting birds alone.
- Use available access ways to get to the beach.
- Avoid leaving old fishing lines on beaches or in the sea.
- Follow the water care code and local navigation bylaws.
- Don't drive on riverbeds, or keep to formed tracks if you have to.
Other ways to help
- Get your dog trained in avian awareness.
- Volunteer to control predators and restore bird habitats.
- Set predator traps on your property.
- Put a bell on your cat's collar and feed it well.