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We report a novel observation of Australian waterbird behaviour: a Brolga Antigone rubicunda preying on eggs of the Australasian Grebe Tachybaptus novaeholliandiae, the first record of birds' eggs in the diet of a crane in Australia. We also report 'water-kicking' by the Australasian Grebe, the first record of this anti-predator behaviour in the species. Neither Brolga diet nor display behaviours of the Australasian Grebe have been systematically investigated, and we suggest avenues for further studies of egg predation and parental defence behaviours in waterbird breeding wetlands. [ABSTRACT FROM AUTHOR]

During surveys of the waterbirds of the Lake Bathurst wetland system on the Southern Tablelands of New South Wales, near Canberra (Australian Capital Territory) in most months from 1980 onwards, Hoary-headed Grebes Poliocephalus poliocephalus were found breeding on only six occasions. Nests were built along islands that formed only when Lake Bathurst and the neighbouring Southern Morass reached specific water depths. At higher and lower water levels, Grebes were present but did not breed. The maximum number of nests in a season was 985, much greater than any reported in the literature, but young were produced in only three seasons. Nest failures resulted from falling water levels, heavy rain (and associated rise in water level) or a wind-induced temporary rise in water level. Partial reflooding of the lake triggered late nesting, in April, but the nests were abandoned as the water level fell. High mobility, congregating at refilling wetlands and attempts to nest late in the season by this species may be responses to the ‘boom and bust’ scenario of inland wetlands. [ABSTRACT FROM AUTHOR]

A breeding pair of Australasian Grebes Tachybaptus novaehollandiae was monitored nearly daily between November 2010 and March 2011. This paper describes the responses of the adults to other waterbirds that came within 5 m of their brood, either provoked or unprovoked. Brood loss was rapid, with only one of five chicks surviving more than 3 weeks. Nine instances of brood-defence were recorded, mostly in the first 2 weeks after hatching, as well as one observation of a chick defending itself. The Dusky Moorhen Gallinula tenebrosa was the main species that prompted reactions from the adult Grebes. A Moorhen was seen trying to prey on Grebe chicks on one or probably two occasions, the first time this has been reported. A Purple Swamphen Porphyrio porphyrio was also attacked by the Grebes, and is a likely potential predator of grebe chicks. Ducks and cormorants were attacked or tolerated on different occasions. [ABSTRACT FROM AUTHOR]

The article presents observations of the breeding activity of Australasian Grebes Tachybaptus novaehollandiae on a flood-retarding basin at the Clayton campus on Monash University in Melbourne, Victoria from 2002-10. Two Grebes built nests in the bulrushes at the western end of the basin from 2006-06 and another two Grebes built a nest among the waterweeds in the northwestern section in 2008 but was destroyed by heavy overnight rain and a rise in water level. One adult and three young birds were seen from March 6-April 22, 2008 and by November 2, 2008 a pair had nested in the bulrushes. Usually one and sometimes two new adult Grebes, in breeding plumage, were present during the second and third weeks of March 2009. Three groups of two Grebes remain intact in April 2009.

The article documents an observation of a Great Crested Grebe Podiceps cristatus offering a dead nestling passerine to its young before eating the dead nestling itself at Lake Bindegolly, a Ramsar site and National Park in Queensland, on September 10, 2011. It explains that birds are not common items of prey for the species as its diet reportedly comprises mainly fish, insects, amphibians, and aquatic invertebrates. Feathers have been recovered from the stomachs of the species, but it has been suggested that they were ingested to wrap fish bones for regurgitation as pellets. It is not known whether the adult Grebe had raided a nest of another species or had picked up a fallen chick from the water.