Australasian little grebe

Tachybaptus novaehollandiae (Stephens, 1826)

New Zealand status: Native

Conservation status: Coloniser

Other names: eastern little grebe, Australasian grebe, Australian little grebe, Australian grebe

Geographical variation: Seven subspecies occur in Indonesia, New Guinea, Solomon Islands, Vanuatu, New Caledonia, Australia and New Zealand. Nominate novaehollandiae occurs in southern New Guinea, Australia and New Zealand.

Australasian little grebe. Adult in breeding plumage. Whangarei Water Treatment Plant, February 2017. Image © Scott Brooks (ourspot) by Scott Brooks

Australasian little grebe. Adult in breeding plumage. Whangarei Water Treatment Plant, February 2017. Image © Scott Brooks (ourspot) by Scott Brooks

Grebes are small to medium-sized aquatic diving birds that use large powerful lobed feet set far back on their body to propel and steer themselves in water. They have relatively long necks and a submarine-like ability to change their buoyancy. Australasian little grebe occurs on small lakes and farm ponds. The smallest of four grebe species that occur in New Zealand, it is a recent coloniser from Australia with the first breeding record from Diamond Lake near Wanaka in 1977. Since then it has established a small breeding population centred around Northland and until c.2000 in Canterbury (where it has since died out). It is closely related to the little grebe of Eurasia and Africa.

Identification                                                                                      

Distinguished in breeding plumage by glossy black head and neck, rufous facial feathering, bright yellow eyes, and small yellow gape-patch at the base of short, black pointed bill. Non-breeding plumage grey-brown above, paler grey-white below and lacks rufous facial markings. Yellow gape-patch fades after breeding. Grey-black legs have large lobed toes. The tail is a short, pointed tuft of dark feathers. Sexes alike; male slightly heavier. Chicks dark brown-black with irregular creamy white striped markings, red-pink eye ring and pinkish-yellow bill with dark brown markings. Juveniles retain striped markings on head and neck until adult plumage develops; bill becomes black with age.

Voice: adults give loud, explosive 'laughing' trill and pit alarm call. Chicks make piping call and peep when begging for food.

Similar species: larger, darker New Zealand dabchick has more extensive rufous red neck front and breast, and lacks small pale yellow gape-patch behind base of bill.

Distribution and habitat

Since first recorded breeding on Lake Diamond near Wanaka in 1977, the Australasian little grebe established small breeding population centred around Northland, the Rotorua Lakes area and Canterbury. There has been a notable increase in range from Northland to Auckland and the Rotorua Lakes area in recent years, but no records from the South Island since 2008. Reduced ground water levels in parts of Canterbury caused some ponds where they bred to dry up. Favours small reed-fringed freshwater lakes, dune lakes and farm ponds rather than large lakes.

Population

The global population is an estimated 25,000-1 million. The New Zealand population was estimated at 50 individuals in 1995.

Threats and conservation

As the Australasian little grebe is abundant in Australia, the small colonising population in New Zealand has not been the focus of any conservation effort. Its preference for small water bodies that may be susceptible to drying up means that there are few sites where they are continuously present in New Zealand.

Breeding

Egg-laying period in Australia mainly September-November with opportunistic breeding recorded during floods, August-April. Young recorded in New Zealand, January-April. Solitary pairs nest on freshwater lakes, sand dune lakes, and farm ponds, anchoring nest to aquatic vegetation. The nest is a pile of aquatic vegetation up to 60 cm deep. Elaborate courtship involves parallel-swimming, forward or hunched displays on water, and similar displays on the nest platform, accompanied by trilling. Monogamous; 4 bluish eggs laid September-November, staining reddish-brown in the nest. 23 day incubation and 8 week chick-rearing period shared. Chicks ride on parents' backs during first weeks until independence.

Behaviour and ecology

Inhabits small shallow freshwater lakes, sand-dune lakes and farm ponds, usually in pairs. May form small flocks outside breeding season. Has submarine-like ability to change its buoyancy, which it does by adjusting the angle at which its dense waterproof feathers are held against its body. This ability allows it to swim high or low in the water and to dive frequently. It can also sink silently beneath the surface when alarmed and use its relatively long neck and head as a 'periscope'. It also 'snorkels' at the surface with its neck and head submerged in search of prey. Aggressive territorial behaviour directed towards intruders includes an upright attack posture with neck held erect, head feathers ruffled and tail tuft cocked; a forward leaning display posture with head and neck extended low over the water, feathers ruffled and wings folded; and water-kicking, splash-diving and token-diving. Appeasement displays include holding head and bill low in the water with neck held slightly forwards and the rear-end underwater. Swallows small feathers to help form pellets to combat gastric parasites. Mainly flies at night.

Food

In Australia eats mainly small fish, snails and aquatic insects which it catches during dives, as well as vegetation and small frogs. The diet is likely to be similar in New Zealand.

Weblinks

http://www.birdlife.org/datazone/speciesfactsheet.php?id=3629

http://en.wikipedia.org/wiki/Australasian_Grebe

References

Heather, B.; Robertson, H. 1996 (rev 2000). The Field Guide to the Birds of New Zealand. Viking, Auckland.

Jaensch, R. April 2012. Detailed data and notes on numbers and trends of waterbirds in Australia and other parts of the Oceania region. Wetlands International - Oceania (5th ed), Waterbird Population Estimates [http://wpe.wetlands.org]

Marchant, S.; Higgins, P.J. (Eds.) 1990. Handbook of Australian, New Zealand and Antarctic birds. Vol.1. Ratites to Ducks. Oxford University Press: Melbourne.

Robertson, C.J.R. et al. 1985. The Complete Book of New Zealand Birds. Reader's Digest. Australia.

Robertson, C.J.R., Hyvonen, P., Fraser, M.J., Pickard, C.R. 2007. Atlas of Bird Distribution in New Zealand: 1992-2004. OSNZ, Wellington, New Zealand.

Tennyson, A.J.D. 2010. Podicipediformes. In: Checklist Committee (OSNZ) 2010. Checklist of the birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica (4th ed.). Ornithological Society of New Zealand & Te Papa Press, Wellington.

Recommended citation

Szabo, M.J. 2013 [updated 2015]. Australasian Little Grebe. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz

Australasian little grebe

Breeding season
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Egg laying dates
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun

Australasian little grebe

Social structure
monogamous
Breeding season
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Nest type
floating platform
Nest description
Small round floating platform of aquatic vegetation with shallow depression in the centre.
Nest height (max)
0.40 m
Maximum number of successful broods
Unknown
Clutch size (mean)
4
Mean egg dimensions (length)
36.00 mm
Mean egg dimensions (width)
25.00 mm
Egg colour
Bluish white usually staining reddish brown in the nest
Egg laying dates
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
Interval between eggs in a clutch
Up to 2 days
Incubation behaviour
shared
Incubation length (mean)
About 23 days
Nestling type
precocial
Nestling period (mean)
Chicks spend first night on nest then carried on adults
Age at fledging (mean)
Unknown
Age at independence (mean)
56 days
Age at first breeding (typical)
Unknown
Maximum longevity
Unknown
Maximum dispersal
Across Tasman Sea from New Zealand to Australia