New Zealand dabchick Poliocephalus rufopectus

New Zealand dabchick
New Zealand dabchick

Description

  • The New Zealand dabchick is only found in New Zealand.
  • It is a small grebe, about a quarter of the weight of the southern crested grebe. It can be distinguished from the Australasian little grebe by the lack of a distinctive brown cap and the lack of a yellow patch of skin between the eye and bill.

Interesting Facts

  • The dabchick is widespread in the North Island on lakes, dams and oxidation ponds.
  • The population is estimated at 1,900-2,000 birds.
  • The species used to be found on South Island lakes, but the last breeding records were from the 1940s. However, a pair began breeding near Takaka in 2012, and another near Blenheim in 2015.
  • New Zealand dabchicks need clear-water lakes and ponds surrounded by dense riparian cover.
  • The reasons for decline and the extirpation of the South Island population are not well understood. A combination of introduced predators, loss of habitat, increased disturbance and declining water quality are thought to be the primary threats.
  • All wetland birds require high quality wetland habitat buffered from the effects of surrounding land management.

Association with Plantations

  • Wetland birds are found in or adjacent to many plantation forests.
  • Wetland birds may be hard to detect due to their elusive behaviour.

Threats

  • Habitat loss and degradation from wetland drainage, loss of riparian margins, and the effects of surrounding landuse.
  • Invasion of exotic plants, which can seriously modify wetlands and reduce suitability for birds.
  • Disturbance and motor wash from recreational boats
  • High predation rates, particularly of pateke, mainly from dogs, cats and mustelids.
  • Mammalian predation may also affect some other wetland bird species, but the extent of the impacts is largely unknown.

Management Options and Methods

  • Habitat protection:
    • Protect important wetland habitats and riparian buffers.
    • Avoid using herbicides or pesticides close to wetlands.
    • Ensure weeds are not inadvertently introduced to wetlands, e.g. via machinery or boats.
    • Consider control options for existing, invasive, wetland weeds.
    • Consider a staged removal of willows to ensure ongoing cover for crakes and ducks.
  • Forest operations:
    • Minimise damage to riparian and wetland habitat during road construction and harvest operations.
    • Avoid grazing wetlands and their margins. Fencing may be appropriate in some situations.
    • Avoid diverting run-off into wetlands.
    • Minimise disturbance during spring breeding.
    • If pateke are present, discuss predator control with neighbours and DOC.
  • Injured or dead wetland birds (particularly the more threatened species, i.e. white heron, bittern and pateke):
    • Place injured birds in a cardboard box (keep shaded) and deliver to a local vet, SPCA, DOC.
    • Call DOC if bird is dead.

Monitoring Options

  • Increase staff and contractor knowledge about wetland birds.
  • For important wetlands that are likely to have the more threatened species, consider undertaking a bird monitoring programme:
    • Counts of pateke flock sites in late summer.
    • Fernbirds, spotless crakes and to a lesser extent marsh crakes and banded rails respond to taped playback calls.
    • The booming calls of bittern are characteristic at dusk in September-October particularly during bright moonlight.
  • Maintain a database of sightings.

Further Information and Support