- The southern crested grebe is a rather spectacular, large bird with a long, sharp bill, long neck, neck ruff and prominent crest.
- Adults are reddish-brown with a white mask and bright, white foreneck.
- The species is known for carrying its young around on its back.
- The crested grebe is found throughout much of the world; the southern subspecies is found in New Zealand and Australia.
- The crested grebe is found on up to as many as 100 lakes of the South Island; most birds breed in central Canterbury and Otago.
- A major decline has occured in many New Zealand regions, except for parts of inland Canterbury. Numbers hit a low of c.200 in the 1980s, but are slowly increasing and the population may now number c.600 birds.
- Grebes have recently been recorded breeding on the Canterbury coast and numbers are increasing in this region.
- The species is declining in Australia.
- Crested grebes require lakes surrounding by vegetation for breeding, such as rushes, sedges, and reeds, but also exotic species such as willows.
Association with Plantations
- Wetland birds are found in and adjacent to many plantation forests.
- Wetland birds may be hard to detect due to their elusive behaviour.
- The southern crested grebe is thought to be threatened by vegetation clearance, terrestrial predators, hydroelectric developments, and disturbance from recreational activities, particularly power boating.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 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 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.
- 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
- New Zealand Birds Online: southern crested grebe.
- Department of Conservation website: Australasian crested grebe.
- New Zealand Geographic: Reflecting on grebes.
- Wetland Restoration: A Handbook for New Zealand Freshwater Systems. Landcare Research - Manaaki Whenua.
- Pest management - Department of Conservation, Regional Councils.